title: Berlin Blockade

text: The US had secretly decided that a unified and neutral Germany would inevitably fall under Soviet domination, with Ambassador Walter Bedell Smith telling General Eisenhower that "in spite of our announced position, we really do not want nor intend to accept German unification on any terms that the Russians might agree to, even though they seem to meet most of our requirements." American planners had privately decided during the war that it would need a strong, allied Germany to assist in the rebuilding of the West European economy.


title: Berlin Blockade

text: To coordinate the economies of the British and United States occupation zones, these were combined on 1 January 1947 into what was referred to as the Bizone (renamed "the Trizone" when France joined on 1 June 1948). After March 1946 the British zonal advisory board (Zonenbeirat) was established, with representatives of the states, the central offices, political parties, trade unions, and consumer organisations. As indicated by its name, the zonal advisory board had no legislative power, but was merely advisory. The Control Commission for Germany – British Element made all decisions with its legislative power. In reaction to the Soviet and British advances, in October 1945 the Office of Military Government, United States (OMGUS) encouraged the states in the US zone to form a co-ordinating body, the so-called Länderrat (council of states), with the power to legislate for the entire US zone. It created its own central bodies (Ausschüsse or joint interstate committees) headed by a secretariat seated in Stuttgart. While the British and Soviet central administrations were allied institutions, these US zone committees were not OMGUS subdivisions, but instead were autonomous bodies of German self-rule under OMGUS supervision.


title: Berlin Blockade

text: Representatives of these three governments, along with the Benelux nations, met twice in London (London 6-Power Conference) in the first half of 1948 to discuss the future of Germany, going ahead despite Soviet threats to ignore any resulting decisions. Eventually the London Agreement on German External Debts, also known as the London Debt Agreement (German: ), was concluded. Under the London Debts Agreement of 1953, the repayable amount was reduced by 50% to about 15 billion marks and stretched out over 30 years, and compared to the fast-growing German economy were of minor impact.


title: Berlin Blockade

text: In response to the announcement of the first of these meetings, in late January 1948, the Soviets began stopping British and American trains to Berlin to check passenger identities. As outlined in an announcement on 7 March 1948, all of the governments present approved the extension of the Marshall Plan to Germany, finalised the economic merger of the western occupation zones in Germany and agreed upon the establishment of a federal system of government for them.


title: Berlin Blockade

text: After a 9 March meeting between Stalin and his military advisers, a secret memorandum was sent to Molotov on 12 March 1948, outlining a plan to force the policy of the western allies into line with the wishes of the Soviet government by "regulating" access to Berlin. The Allied Control Council (ACC) met for the last time on 20 March 1948, when Vasily Sokolovsky demanded to know the outcome of the London Conference and, on being told by negotiators that they had not yet heard the final results from their governments, he said, "I see no sense in continuing this meeting, and I declare it adjourned."


title: Berlin Blockade

text: The entire Soviet delegation rose and walked out. Truman later noted, "For most of Germany, this act merely formalised what had been an obvious fact for some time, namely, that the four-power control machinery had become unworkable. For the city of Berlin, however, this was an indication for a major crisis."


title: Berlin Blockade

text: On 25 March 1948, the Soviets issued orders restricting Western military and passenger traffic between the American, British and French occupation zones and Berlin. These new measures began on 1 April along with an announcement that no cargo could leave Berlin by rail without the permission of the Soviet commander. Each train and truck was to be searched by the Soviet authorities. On 2 April, General Clay ordered a halt to all military trains and required that supplies to the military garrison be transported by air, in what was dubbed the "Little Lift."


title: Berlin Blockade

text: The Soviets eased their restrictions on Allied military trains on 10 April 1948, but continued periodically to interrupt rail and road traffic during the next 75 days, while the United States continued supplying its military forces by using cargo aircraft. Some 20 flights a day continued through June, building up stocks of food against future Soviet actions, so that by the time the blockade began at the end of June, at least 18 days' supply per major food type, and in some types, much more, had been stockpiled that provided time to build up the ensuing airlift.


title: Berlin Blockade

text: At the same time, Soviet military aircraft began to violate West Berlin airspace and would harass, or what the military called "buzz", flights in and out of West Berlin. On 5 April, a Soviet Air Force Yakovlev Yak-3 fighter collided with a British European Airways Vickers Viking 1B airliner near RAF Gatow airfield, killing all aboard both aircraft. Later dubbed the Gatow air disaster, this event exacerbated tensions between the Soviets and the other allied powers.


title: Berlin Blockade

text: Internal Soviet reports in April stated that "Our control and restrictive measures have dealt a strong blow to the prestige of the Americans and British in Germany" and that the Americans have "admitted" that the idea of an airlift would be too expensive.


title: Berlin Blockade

text: On 9 April, Soviet officials demanded that American military personnel maintaining communication equipment in the Eastern zone must withdraw, thus preventing the use of navigation beacons to mark air routes. On 20 April, the Soviets demanded that all barges obtain clearance before entering the Soviet zone.


title: Berlin Blockade

text: Creation of an economically stable western Germany required reform of the unstable Reichsmark German currency introduced after the 1920s German inflation. The Soviets continued the debasing of the Reichsmark, which had undergone severe inflation during the war, by excessive printing, resulting in many Germans using cigarettes as a de facto currency or for bartering. The Soviets opposed western plans for a reform. They interpreted the new currency as an unjustified, unilateral decision, and responded by cutting all land links between West Berlin and West Germany. The Soviets believed that the only currency that should be allowed to circulate was the currency that they issued themselves.


title: Berlin Blockade

text: Anticipating the introduction of a new currency by the other countries in the non-Soviet zones, the Soviet Union in May 1948 directed its military to introduce its own new currency and to permit only the Soviet currency to be used in their sector of Berlin if the other countries brought in a different currency there. On 18 June the United States, Britain and France announced that on 21 June the Deutsche Mark would be introduced, but the Soviets refused to permit its use as legal tender in Berlin. The Allies had already transported 250,000,000 Deutsche marks into the city and it quickly became the standard currency in all four sectors. Stalin looked to force the Western nations to abandon Berlin.


title: Berlin Blockade

text: The day after the 18 June 1948 announcement of the new Deutsche Mark, Soviet guards halted all passenger trains and traffic on the autobahn to Berlin, delayed Western and German freight shipments and required that all water transport secure special Soviet permission. On 21 June, the day the Deutsche Mark was introduced, the Soviet military halted a United States military supply train to Berlin and sent it back to western Germany. On 22 June, the Soviets announced that they would introduce the East German mark in their zone.


title: Berlin Blockade

text: That same day, a Soviet representative told the other three occupying powers that "We are warning both you and the population of Berlin that we shall apply economic and administrative sanctions that will lead to the circulation in Berlin exclusively of the currency of the Soviet occupation zone." The Soviets launched a massive propaganda campaign condemning Britain, the United States and France by radio, newspaper and loudspeaker. The Soviets conducted well-advertised military maneuvers just outside the city. Rumors of a potential occupation by Soviet troops spread quickly. German communists demonstrated, rioted and attacked pro-West German leaders attending meetings for the municipal government in the Soviet sector.


title: Berlin Blockade

text: On 24 June, the Soviets severed land and water connections between the non-Soviet zones and Berlin. That same day, they halted all rail and barge traffic in and out of Berlin. The West answered by introducing a counter-blockade, stopping all rail traffic into East Germany from the British and US zones. Over the following months, this counter-blockade would have a damaging impact on East Germany, as the drying up of coal and steel shipments seriously hindered industrial development in the Soviet zone. On 25 June, the Soviets stopped supplying food to the civilian population in the non-Soviet sectors of Berlin. Motor traffic from Berlin to the western zones was permitted, but this required a detour to a ferry crossing because of alleged "repairs" to a bridge. They also cut off the electricity relied on by Berlin, using their control over the generating plants in the Soviet zone.


title: Berlin Blockade

text: Surface traffic from non-Soviet zones to Berlin was blockaded, leaving open only the air corridors. The Soviets rejected arguments that the occupation rights in the non-Soviet sectors of Berlin and the use of the supply routes during the previous three years had given Britain, France and the United States a legal claim to use of the highways, tunnels, railroads, and canals. Relying on Soviet goodwill after the war, Britain, France, and the United States had never negotiated an agreement with the Soviets to guarantee these land-based rights of access to Berlin through the Soviet zone.


title: Berlin Blockade

text: At the time, West Berlin had an estimated 36 days worth of food, and 45 days worth of coal. Militarily, the Americans and British were greatly outnumbered because of the postwar scaling back of their armies. The United States, like other western countries, had disbanded most of its troops and was largely inferior in the European theatre. The entire United States Army had been reduced to 552,000 men by February 1948. Military forces in the western sectors of Berlin numbered only 8,973 Americans, 7,606 British and 6,100 French. Of the 98,000 American troops in West Germany in March 1948, only 31,000 were combat forces, and only one reserve division was immediately available in the United States. Soviet military forces in the Soviet sector that surrounded Berlin totaled 1.5 million. The two United States regiments in Berlin could have provided little resistance against a Soviet attack. Because of the imbalance, US war plans were based on using hundreds of atomic bombs, but only about 50 Fat Man-specification bombs, the only version available to the US military, existed in mid-1948. In March 1948, only 35 "Silverplate" atomic-capable Boeing B-29 Superfortress bombers—just over half of the 65 "Silverplate" specification B-29 aircraft built through the end of 1947—and a few trained flight and assembly crews were available. Three B-29 groups arrived in Europe in July and August 1948. Despite the intention to signal the threat of the West's ability to retaliate with nuclear weapons if necessary, the Soviets possibly knew that none of the bombers were atomic-capable. The first Silverplate bombers only arrived in Europe near the end of the crisis in April 1949.


title: Berlin Blockade

text: General Lucius D. Clay, in charge of the US Occupation Zone in Germany, summed up the reasons for not retreating in a cable to Washington, D.C. on 13 June 1948:


title: Berlin Blockade

text: Believing that Britain, France, and the United States had little option other than to acquiesce, the Soviet Military Administration in Germany celebrated the beginning of the blockade. General Clay felt that the Soviets were bluffing about Berlin since they would not want to be viewed as starting a Third World War. He believed that Stalin did not want a war and that Soviet actions were aimed at exerting military and political pressure on the West to obtain concessions, relying on the West's prudence and unwillingness to provoke a war. Commander of United States Air Forces in Europe (USAFE) General Curtis LeMay reportedly favoured an aggressive response to the blockade, in which his B-29s with fighter escort would approach Soviet air bases while ground troops attempted to reach Berlin; Washington vetoed the plan.


title: Berlin Blockade

text: Although the ground routes had never been negotiated, the same was not true of the air. On 30 November 1945, it had been agreed in writing that there would be three twenty-mile-wide air corridors providing free access to Berlin. Additionally, unlike a force of tanks and trucks, the Soviets could not claim that cargo aircraft were a military threat.


title: Berlin Blockade

text: The airlift option critically depended on scale and effectiveness. If the supplies could not be flown in fast enough, Soviet help would eventually be needed to prevent starvation. Clay was told to take advice from General LeMay to see if an airlift was possible. Initially taken aback by the inquiry, which was "Can you haul coal?", LeMay replied, "We can haul anything."


title: Berlin Blockade

text: When American forces consulted Britain's Royal Air Force about a possible joint airlift, they learned the RAF was already running an airlift in support of British troops in Berlin. General Clay's counterpart, General Sir Brian Robertson, was ready with some concrete numbers. During the "Little Lift" in April 1948, British Air Commodore Reginald Waite had calculated the resources required to support the entire city.


title: Berlin Blockade

text: The American military government, based on a minimum daily ration of 1,990 kilocalories (July 1948), set a total of daily supplies needed at 646 tons of flour and wheat, 125 tons of cereal, 64 tons of fat, 109 tons of meat and fish, 180 tons of dehydrated potatoes, 180 tons of sugar, 11 tons of coffee, 19 tons of powdered milk, 5 tons of whole milk for children, 3 tons of fresh yeast for baking, 144 tons of dehydrated vegetables, 38 tons of salt and 10 tons of cheese. In all, 1,534 tons were required each day to sustain the over two million people of Berlin. Additionally, for heat and power, 3,475 tons of coal, diesel and petrol were also required daily.


title: Berlin Blockade

text: Carrying all this in would not be easy. The postwar demobilisation left the US forces in Europe with only two groups of C-47 Skytrain transports (the military version of the Douglas DC-3, which the British called the "Dakota"), nominally 96 aircraft, each of which could carry about 3.5 tons of cargo. LeMay believed that "with an all-out effort" of 100 daily round trips these would be able to haul about 300 tons of supplies a day. The RAF was somewhat better prepared, since it had already moved some aircraft into the German area, and they expected to be able to supply about 400 tons a day.


title: Berlin Blockade

text: This was not nearly enough to move the 5,000 tons a day that would be needed, but these numbers could be increased as new aircraft arrived from the United Kingdom, the United States, and France. The RAF would be relied on to increase its numbers quickly. It could fly additional aircraft in from Britain in a single hop, bringing the RAF fleet to about 150 Dakotas and 40 of the larger Avro Yorks with a 10-ton payload.


title: Berlin Blockade

text: With this fleet, the British contribution was expected to rise to 750 tons a day in the short term, albeit at the cost of suspending all air traffic except for the airlift to Berlin. For a longer-term operation, the US would have to add additional aircraft as soon as possible, and those would have to be as large as possible while still able to fly into the Berlin airports. Only one aircraft type was suitable, the four-engined C-54 Skymaster and its US Navy equivalent, the R5D, of which the US military had approximately 565, with 268 Air Force and Navy Skymasters in MATS, 168 in the troop carrier groups, and 80 Navy R5Ds in miscellaneous commands. Planners calculated that including C-54s already ordered to Germany and drawing on those flying with civilian carriers, 447 Skymasters could be available for an "extreme emergency".


title: Berlin Blockade

text: Given the feasibility assessment made by the British, an airlift appeared to be the best course of action. One remaining concern was the population of Berlin. Clay called in Ernst Reuter, the mayor-elect of Berlin, accompanied by his aide, Willy Brandt. Clay told Reuter:


title: Berlin Blockade

text: Reuter, although skeptical, assured Clay that Berlin would make all the necessary sacrifices and that the Berliners would support his actions.


title: Berlin Blockade

text: General Albert Wedemeyer, the US Army Chief of Plans and Operations, was in Europe on an inspection tour when the crisis broke out. He had been the commander of the US China Burma India Theater in 1944–45 and he had a detailed knowledge of the previously largest airlift—the World War II American airlift from India over the Hump of the Himalayas to China. His endorsement of the airlift option gave it a major boost. The British and Americans agreed to start a joint operation without delay; the US action was dubbed "Operation Vittles", while the British action was called "Operation Plainfare". The Australian contribution to the airlift, begun in September 1948, was designated "Operation Pelican".


title: Berlin Blockade

text: The British asked Canada to contribute planes and crews. It refused, primarily on the grounds that the operation risked war and Canada had not been consulted.


title: Berlin Blockade

text: On 24 June 1948 LeMay appointed Brigadier General Joseph Smith, headquarters commandant for USAFE at Camp Lindsey, as the Provisional Task Force Commander of the airlift. Smith had been chief of staff in LeMay's B-29 command in India during World War II and had no airlift experience. On 25 June 1948 Clay gave the order to launch Operation Vittles. The next day 32 C-47s lifted off for Berlin hauling 80 tons of cargo, including milk, flour, and medicine. The first British aircraft flew on 28 June. At that time, the airlift was expected to last three weeks.


title: Berlin Blockade

text: By 1 July, the system was getting under way. C-54s were starting to arrive in quantity, and Rhein-Main Air Base became exclusively a C-54 hub, while Wiesbaden retained a mix of C-54s and C-47s. Aircraft flew northeast through the American air corridor into Tempelhof Airport, then returned due west flying out on through the British air corridor. After reaching the British Zone, they turned south to return to their bases.


title: Berlin Blockade

text: The British ran a similar system, flying southeast from several airports in the Hamburg area through their second corridor into RAF Gatow in the British Sector, and then also returning out on the center corridor, turning for home or landing at Hanover. However, unlike the Americans, the British also ran some round-trips, using their southeast corridor. To save time many flights didn't land in Berlin, instead air dropping material, such as coal, into the airfields. On 6 July the Yorks and Dakotas were joined by Short Sunderland flying boats. Flying from Finkenwerder on the Elbe near Hamburg to the Havel river next to Gatow, their corrosion-resistant hulls suited them to the particular task of delivering baking powder and other salt into the city. The Royal Australian Air Force also contributed to the British effort.


title: Berlin Blockade

text: Accommodating the large number of flights to Berlin of dissimilar aircraft with widely varying flight characteristics required close co-ordination. Smith and his staff developed a complex timetable for flights called the "block system": three eight-hour shifts of a C-54 section to Berlin followed by a C-47 section. Aircraft were scheduled to take off every four minutes, flying higher than the flight in front. This pattern began at and was repeated five times. This system of stacked inbound serials was later dubbed "the ladder".


title: Berlin Blockade

text: During the first week the airlift averaged only ninety tons a day, but by the second week it reached 1,000 tons. This likely would have sufficed had the effort lasted only a few weeks, as originally believed. The Communist press in East Berlin ridiculed the project. It derisively referred to "the futile attempts of the Americans to save face and to maintain their untenable position in Berlin."


title: Berlin Blockade

text: Despite the excitement engendered by glamorous publicity extolling the work (and over-work) of the crews and the daily increase of tonnage levels, the airlift was not close to being operated to its capability because USAFE was a tactical organisation without any airlift expertise. Maintenance was barely adequate, crews were not being efficiently used, transports stood idle and disused, necessary record-keeping was scant, and ad hoc flight crews of publicity-seeking desk personnel were disrupting a business-like atmosphere. This was recognised by the United States National Security Council at a meeting with Clay on 22 July 1948, when it became clear that a long-term airlift was necessary. Wedemeyer immediately recommended that the deputy commander for operations of the Military Air Transport Service (MATS), Maj. Gen. William H. Tunner, command the operation. When Wedemeyer had been the commander of US forces in China during World War II, Tunner, as commander of the India-China Division of the Air Transport Command, had reorganised the Hump airlift between India and China, doubling the tonnage and hours flown. USAF Chief of Staff Hoyt S. Vandenberg endorsed the recommendation.


title: Berlin Blockade

text: On 28 July 1948, Tunner arrived in Wiesbaden to take over the operation. He revamped the entire airlift operation, reaching an agreement with LeMay to form the "Combined Air Lift Task Force" (CALTF) to control both the USAFE and RAF lift operations from a central location, which went into effect in mid-October 1948. MATS immediately deployed eight squadrons of C-54s—72 aircraft—to Wiesbaden and Rhein-Main Air Base to reinforce the 54 already in operation, the first by 30 July and the remainder by mid-August, and two-thirds of all C-54 aircrew worldwide began transferring to Germany to allot three crews per aircraft.


title: Berlin Blockade

text: Two weeks after his arrival, on 13 August, Tunner decided to fly to Berlin to grant an award to Lt. Paul O. Lykins, an airlift pilot who had made the most flights into Berlin up to that time, a symbol of the entire effort to date. Cloud cover over Berlin dropped to the height of the buildings, and heavy rain showers made radar visibility poor. A C-54 crashed and burned at the end of the runway, and a second one landing behind it burst its tires while trying to avoid it. A third transport ground looped after mistakenly landing on a runway under construction. In accordance with the standard procedures then in effect, all incoming transports including Tunner's, arriving every three minutes, were stacked above Berlin by air traffic control from to in bad weather, creating an extreme risk of mid-air collision. Newly unloaded planes were denied permission to take off to avoid that possibility and created a backup on the ground. While no one was killed, Tunner was embarrassed that the control tower at Tempelhof had lost control of the situation while the commander of the airlift was circling overhead. Tunner radioed for all stacked aircraft except his to be sent home immediately. This became known as "Black Friday", and Tunner personally noted it was from that date onward that the success of the airlift stemmed.


title: Berlin Blockade

text: As a result of Black Friday, Tunner instituted a number of new rules; instrument flight rules (IFR) would be in effect at all times, regardless of actual visibility, and each sortie would have only one chance to land in Berlin, returning to its air base if it missed its approach, where it was slotted back into the flow. Stacking was completely eliminated. With straight-in approaches, the planners found that in the time it had taken to unstack and land nine aircraft, 30 aircraft could be landed, bringing in 300 tons. Accident rates and delays dropped immediately. Tunner decided, as he had done during the Hump operation, to replace the C-47s in the airlift with C-54s or larger aircraft when it was realised that it took just as long to unload a 3.5-ton C-47 as a 10-ton C-54. One of the reasons for this was the sloping cargo floor of the "taildragger" C-47s, which made truck loading difficult. The tricycle geared C-54's cargo deck was level, so that a truck could back up to it and offload cargo quickly. The change went into full effect after 28 September 1948.


title: Berlin Blockade

text: Having noticed on his first inspection trip to Berlin on 31 July that there were long delays as the flight crews returned to their aircraft after getting refreshments from the terminal, Tunner banned aircrew from leaving their aircraft for any reason while in Berlin. Instead, he equipped jeeps as mobile snack bars, handing out refreshments to the crews at their aircraft while it was being unloaded. Airlift pilot Gail Halvorsen later noted, "he put some beautiful German Fräuleins in that snack bar. They knew we couldn't date them, we had no time. So they were very friendly." Operations officers handed pilots their clearance slips and other information while they ate. With unloading beginning as soon as engines were shut down on the ramp, turnaround before takeoff back to Rhein-Main or Wiesbaden was reduced to thirty minutes.


title: Berlin Blockade

text: To maximise the utilisation of a limited number of aircraft, Tunner altered the "ladder" to three minutes and of separation, stacked from to . Maintenance, particularly adherence to 25-hour, 200-hour, and 1,000-hour inspections, became the highest priority and further maximised utilisation. Tunner also shortened block times to six hours to squeeze in another shift, making 1,440 (the number of minutes in a day) landings in Berlin a daily goal. His purpose, illustrating his basic philosophy of the airlift business, was to create a "conveyor belt" approach to scheduling that could be sped up or slowed down as situations might dictate. The most effective measure taken by Tunner, and the most initially resisted until it demonstrated its efficiency, was creation of a single control point in the CALTF for controlling all air movements into Berlin, rather than each air force doing its own.


title: Berlin Blockade

text: The Berliners themselves solved the problem of the lack of manpower. Crews unloading and making airfield repairs at the Berlin airports were made up almost entirely of local civilians, who were given additional rations in return. As the crews increased in experience, the times for unloading continued to fall, with a record set for the unloading of an entire 10-ton shipment of coal from a C-54 in ten minutes, later beaten when a twelve-man crew unloaded the same quantity in five minutes and 45 seconds.


title: Berlin Blockade

text: By the end of August 1948, after two months, the Airlift was succeeding; daily operations flew more than 1,500 flights a day and delivered more than 4,500 tons of cargo, enough to keep West Berlin supplied. From January 1949 onwards, 225 C-54s (40% of USAF and USN Skymasters worldwide) were devoted to the lift. Supplies improved to 5,000 tons a day.


title: Berlin Blockade

text: Gail Halvorsen, one of the many Airlift pilots, decided to use his off-time to fly into Berlin and make movies with his hand-held camera. He arrived at Tempelhof on 17 July 1948 on one of the C-54s and walked over to a crowd of children who had gathered at the end of the runway to watch the aircraft. He introduced himself and they started to ask him questions about the aircraft and their flights. As a goodwill gesture, he handed out his only two sticks of Wrigley's Doublemint Gum. The children quickly divided up the pieces as best they could, even passing around the wrapper for others to smell. He was so impressed by their gratitude and that they didn't fight over them, that he promised the next time he returned he would drop off more. Before he left them, a child asked him how they would know it was him flying over. He replied, "I'll wiggle my wings."


title: Berlin Blockade

text: The next day on his approach to Berlin, he rocked the aircraft and dropped some chocolate bars attached to a handkerchief parachute to the children waiting below. Every day after that, the number of children increased and he made several more drops. Soon, there was a stack of mail in Base Ops addressed to "Uncle Wiggly Wings", "The Chocolate Uncle" and "The Chocolate Flier". His commanding officer was upset when the story appeared in the news, but when Tunner heard about it, he approved of the gesture and immediately expanded it into "Operation Little Vittles". Other pilots participated, and when news reached the US, children all over the country sent in their own candy to help out. Soon, major candy manufacturers joined in. In the end, over three tons of candy were dropped on Berlin and the "operation" became a major propaganda success. German children christened the candy-dropping aircraft "raisin bombers" or candy bombers.


title: Berlin Blockade

text: The Soviets had an advantage in conventional military forces, but were preoccupied with rebuilding their war-torn economy and society. The US had a stronger navy and air force, and had nuclear weapons. Neither side wanted a war; the Soviets did not disrupt the airlift.


title: Berlin Blockade

text: As the tempo of the airlift grew, it became apparent that the Western powers might be able to pull off the impossible: indefinitely supplying an entire city by air alone. In response, starting on 1 August 1948, the Soviets offered free food to anyone who crossed into East Berlin and registered their ration cards there, and almost 22 thousand Berliners received their cards until 4 August 1948. In 1949 more than 100 thousand West Berliners were receiving Soviet supplies in Eastern Berlin. Some West Berliners rejected Soviet offers of food.


title: Berlin Blockade

text: Throughout the airlift, Soviet and German communists subjected the hard-pressed West Berliners to sustained psychological warfare. In radio broadcasts, they relentlessly proclaimed that all Berlin came under Soviet authority and predicted the imminent abandonment of the city by the Western occupying powers. The Soviets also harassed members of the democratically elected citywide administration, which had to conduct its business in the city hall located in the Soviet sector.


title: Berlin Blockade

text: During the early months of the airlift, the Soviets used various methods to harass allied aircraft. These included buzzing by Soviet planes, obstructive parachute jumps within the corridors, and shining searchlights to dazzle pilots at night. Although the USAFE reported 733 separate harassing events, including flak, air-to-air fire, rocketing, bombing, and explosions, this is now considered to be exaggerated. None of these measures were effective. Former RAF Dakota pilot Dick Arscott described one "buzzing" incident. "Yaks (Soviet fighter aircraft) used to come and buzz you and go over the top of you at about twenty feet which can be off-putting. One day I was buzzed about three times. The following day it started again and he came across twice and I got a bit fed up with it. So when he came for the third time, I turned the aircraft into him and it was a case of chicken, luckily he was the one who chickened out."


title: Berlin Blockade

text: In the autumn of 1948 it became impossible for the non-Communist majority in Greater Berlin's citywide parliament to attend sessions at city hall within the Soviet sector. The parliament () had been elected under the provisional constitution of Berlin two years earlier (20 October 1946). As SED-controlled policemen looked on passively, Communist-led mobs repeatedly invaded the "Neues Stadthaus", the provisional city hall (located on Parochialstraße since all other central municipal buildings had been destroyed in the War), interrupted the parliament's sessions, and menaced its non-Communist members. The Kremlin organised an attempted putsch for control of all of Berlin through a 6 September takeover of the city hall by SED members.


title: Berlin Blockade

text: Three days later RIAS Radio urged Berliners to protest against the actions of the communists. On 9 September 1948 a crowd of 500,000 people gathered at the Brandenburg Gate, next to the ruined Reichstag in the British sector. The airlift was working so far, but many West Berliners feared that the Allies would eventually discontinue it. Then-SPD city councillor Ernst Reuter took the microphone and pleaded for his city, "You peoples of the world, you people of America, of England, of France, look on this city, and recognise that this city, this people, must not be abandoned—cannot be abandoned!"


title: Berlin Blockade

text: The crowd surged towards the Soviet-occupied sector and someone climbed up and ripped down the Soviet flag flying from atop the Brandenburg Gate. Soviet military police (MPs) quickly responded, resulting in the killing of one in the unruly crowd. The tense situation could have escalated further and ended up in more bloodshed but a British deputy provost then intervened and pointedly pushed the Soviet MPs back with his swagger stick. Never before this incident had so many Berliners gathered in unity. The resonance worldwide was enormous, notably in the United States, where a strong feeling of solidarity with Berliners reinforced a general widespread determination not to abandon them.


title: Berlin Blockade

text: Berlin's parliament decided to meet instead in the canteen of the Technical College of Berlin-Charlottenburg in the British sector, boycotted by the members of SED, which had gained 19.8% of the electoral votes in 1946. On 30 November 1948 the SED gathered its elected parliament members and 1,100 further activists and held an unconstitutional so-called "extraordinary city assembly" () in East Berlin's Metropol-Theater which declared the elected city government () and its democratically elected city councillors to be deposed and replaced it with a new one led by Oberbürgermeister Friedrich Ebert Jr. and consisting only of Communists. This arbitrary act had no legal effect in West Berlin, but the Soviet occupants prevented the elected city government for all of Berlin from further acting in the eastern sector.


title: Berlin Blockade

text: The city parliament, boycotted by its SED members, then voted for its re-election on 5 December 1948, however, inhibited in the eastern sector and defamed by the SED as a ("divisive election"). The SED did not nominate any candidates for this election and appealed to the electorate in the western sectors to boycott the election, while the democratic parties ran for seats. The turnout amounted to 86.3% of the western electorate with the SPD gaining 64.5% of the votes (= 76 seats), the CDU 19.4% (= 26 seats), and the Liberal-Demokratische Partei (LDP, merged in the FDP in 1949) 16.1% (= 17 seats).


title: Berlin Blockade

text: On 7 December the new, "de facto" West-Berlin-only city parliament elected a new city government in West Berlin headed by Lord Mayor Reuter, who had already once been elected lord mayor in early 1946 but prevented from taking office by a Soviet veto. Thus two separate city governments officiated in the city divided into East and West versions of its former self. In the east, a communist system supervised by house, street, and block wardens was quickly implemented.


title: Berlin Blockade

text: West Berlin's parliament accounted for the "de facto" political partition of Berlin and replaced the provisional constitution of Berlin by the (constitution of Berlin), meant for all Berlin, with effect of 1 October 1950 and "de facto" restricted to the western sectors only, also renaming city parliament (from to "Abgeordnetenhaus von Berlin"), city government (from to Senate of Berlin), and head of government (from to Governing Mayor of Berlin).


title: Berlin Blockade

text: Although the early estimates were that about 4,000 to 5,000 tons per day would be needed to supply the city, this was made in the context of summer weather, when the Airlift was only expected to last a few weeks. As the operation dragged on into autumn, the situation changed considerably. The food requirements would remain the same (around 1,500 tons), but the need for additional coal to heat the city dramatically increased the total amount of cargo to be transported by an additional 6,000 tons a day.


title: Berlin Blockade

text: To maintain the Airlift under these conditions, the current system would have to be greatly expanded. Aircraft were available, and the British started adding their larger Handley Page Hastings in November, but maintaining the fleet proved to be a serious problem. Tunner looked to the Germans once again, hiring (plentiful) ex-Luftwaffe ground crews.


title: Berlin Blockade

text: Another problem was the lack of runways in Berlin to land on: two at Tempelhof and one at Gatow—neither of which was designed to support the loads the C-54s were putting on them. All of the existing runways required hundreds of labourers, who ran onto them between landings and dumped sand into the runway's Marston Mat (pierced steel planking) to soften the surface and help the planking survive. Since this system could not endure through the winter, between July and September 1948 a 6,000 ft.-long asphalt runway was constructed at Tempelhof.


title: Berlin Blockade

text: Far from ideal, with the approach being over Berlin's apartment blocks, the runway nevertheless was a major upgrade to the airport's capabilities. With it in place, the auxiliary runway was upgraded from Marston Matting to asphalt between September and October 1948. A similar upgrade program was carried out by the British at Gatow during the same period, also adding a second runway, using concrete.


title: Berlin Blockade

text: The French Air Force, meanwhile, had become involved in the First Indochina War, so it could only bring up a few French built Junkers Ju 52s (known as A.A.C. 1 "Toucan") to support its own troops, and they were too small and slow to be of much help. However, France agreed to build a complete, new and larger airport in its sector on the shores of Lake Tegel. French military engineers, managing German construction crews, were able to complete the construction in under 90 days. Because of a shortage of heavy equipment, the first runway was mostly built by hand, by thousands of labourers who worked day and night.


title: Berlin Blockade

text: For the second runway at Tegel, heavy equipment was needed to level the ground, equipment that was too large and heavy to fly in on any existing cargo aircraft. The solution was to dismantle large machines and then re-assemble them. Using the five largest American C-82 Packet transports, it was possible to fly the machinery into West Berlin. This not only helped to build the airfield, but also demonstrated that the Soviet blockade could not keep anything out of Berlin. The Tegel airfield was subsequently developed into Berlin Tegel Airport.


title: Berlin Blockade

text: To improve air traffic control, which would be critical as the number of flights grew, the newly developed ground-controlled approach radar system (GCA) was flown to Europe for installation at Tempelhof, with a second set installed at Fassberg in the British Zone in West Germany. With the installation of GCA, all-weather airlift operations were assured.


title: Berlin Blockade

text: November and December 1948 proved to be the worst months of the airlift operation for the Western Allies. One of the longest-lasting fogs ever experienced in Berlin blanketed the entire European continent for weeks. All too often, aircraft would make the entire flight and then be unable to land in Berlin. On 20 November 1948, 42 aircraft departed for Berlin, but only one landed there. At one point, the city had only a week's supply of coal left. However, the weather eventually improved, and more than 171,000 tons were delivered in January 1949, 152,000 tons in February, and 196,223 tons in March.


title: Berlin Blockade

text: By April 1949, airlift operations were running smoothly and Tunner wanted to shake up his command to discourage complacency. He believed in the spirit of competition between units and, coupled with the idea of a big event, felt that this would encourage them to greater efforts. He decided that, on Easter Sunday, the airlift would break all records. To do this, maximum efficiency was needed and so, to simplify cargo-handling, only coal would be airlifted. Coal stockpiles were built up for the effort and maintenance schedules were altered so that the maximum number of aircraft were available.


title: Berlin Blockade

text: From noon on 15 April to noon on 16 April 1949, crews worked around the clock. When it was over, 12,941 tons of coal had been delivered in 1,383 flights, without a single accident. A welcome side effect of the effort was that operations in general were boosted, and tonnage increased from 6,729 tons to 8,893 tons per day thereafter. In total, the airlift delivered 234,476 tons in April.


title: Berlin Blockade

text: On 15 April 1949, the Soviet news agency TASS reported a willingness by the Soviets to lift the blockade. The next day, the US State Department stated that the "way appears clear" for the blockade to end. Soon afterwards, the four powers began serious negotiations, and a settlement was reached on Western terms. On 4 May 1949, the Allies announced an agreement to end the blockade in eight days.


title: Berlin Blockade

text: The Soviet blockade of Berlin was lifted at one minute after midnight on 12 May 1949. A British convoy immediately drove through to Berlin, and the first train from West Germany reached Berlin at 5:32 a.m. Later that day, an enormous crowd celebrated the end of the blockade. General Clay, whose retirement had been announced by US President Truman on 3 May 1949, was saluted by 11,000 US soldiers and dozens of aircraft. Once home, Clay received a ticker tape parade in New York City, was invited to address the US Congress, and was honoured with a medal from President Truman.


title: Berlin Blockade

text: Nevertheless, supply flights to Berlin continued for some time to build up a comfortable surplus, though night flying and then weekend flights could be eliminated once the surplus was large enough. By 24 July 1949, three months' worth of supplies had been amassed, ensuring that there was ample time to restart the Airlift if needed.


title: Berlin Blockade

text: On 18 August 1949, Flt Lt Roy Mather DFC AFC and his crew of Flt Lt Roy Lewis Stewart Hathaway AFC, Flt Lt Richardson and Royston William Marshall AFM of 206 squadron, flew back to Wunstorf for the 404th time during the blockade, the record number of flights for any pilot of any nationality, either civilian or military.


title: Berlin Blockade

text: The Berlin Airlift officially ended on 30 September 1949, after fifteen months. In total, the USAF delivered 1,783,573 tons and the RAF 541,937 tons, totalling 2,326,406 tons, nearly two-thirds of which was coal, on 278,228 flights to Berlin. The Royal Australian Air Force delivered 7,968 tons of freight and 6,964 passengers during 2,062 sorties. The C-47s and C-54s together flew over in the process, almost the distance from Earth to the Sun. At the height of the Airlift, one plane reached West Berlin every thirty seconds.


title: Berlin Blockade

text: Pilots came from the United States, United Kingdom, Australia, Canada, New Zealand, and South Africa.


title: Berlin Blockade

text: A total of 101 fatalities were recorded as a result of the operation, including 40 Britons and 31 Americans, mostly due to non-flying accidents. One Royal Australian Air Force member was killed in an aircraft crash at Lübeck while attached to No. 27 Squadron RAF. Seventeen American and eight British aircraft crashed during the operation.


title: Berlin Blockade

text: The cost of the Airlift was shared between the US, UK, and German authorities in the Western sectors of occupation. Estimated costs range from approximately US$224 million to over US$500 million (equivalent to approximately $ to $ now).


title: Berlin Blockade

text: Operational control of the three Allied air corridors was assigned to BARTCC (Berlin Air Route Traffic Control Center) air traffic control located at Tempelhof. Diplomatic approval was granted by a four-power organisation called the Berlin Air Safety Center, also located in the American sector.


title: Berlin Blockade

text: Millions of East Germans escaped to West Germany from East Germany, and Berlin became a major escape route. This led to major-power conflict over Berlin that stretched at least from 1946 to the construction of the Berlin Wall in 1961. Dwight D. Eisenhower became US President in 1953 and Nikita Khrushchev became Soviet leader in the same year. Khrushchev tried to push Eisenhower on Berlin in 1958–59. The Soviets backed down when Eisenhower's resolve seemed to match that of Truman. When Eisenhower was replaced by Kennedy in 1961, Khrushchev tried again, with essentially the same result.


title: Berlin Blockade

text: In the late 1950s, the runways at West Berlin's city centre Tempelhof Airport had become too short to accommodate the new-generation jet aircraft, and Tegel was developed into West Berlin's principal airport. During the 1970s and 1980s Schönefeld had its own crossing points through the Berlin Wall and communist fortifications for western citizens.


title: Berlin Blockade

text: The Soviets' contravention by the blockade of the agreement reached by the London 6-Power Conference, and the Czechoslovak coup d'état of 1948, convinced Western leaders that they had to take swift and decisive measures to strengthen the portions of Germany not occupied by the Soviets.


title: Berlin Blockade

text: The US, British and French authorities also agreed to replace their military administrations in their occupation zones with High Commissioners operating within the terms of a three-power occupation statute. The Blockade also helped to unify German politicians in these zones in support of the creation of a West German state; some of them had hitherto been fearful of Soviet opposition. The blockade also increased the perception among many Europeans that the Soviets posed a danger, helping to prompt the entry into NATO of Portugal, Iceland, Italy, Denmark, and Norway.


title: Berlin Blockade

text: It has been claimed that animosities between Germans and the Western Allies were greatly reduced by the airlift, with the former enemies recognising common interests. The Soviets refused to return to the Allied Control Council in Berlin, rendering the four-power occupation authority set up at the Potsdam Conference useless. It has been argued that the events of the Berlin Blockade are proof that the Allies conducted their affairs within a rational framework, since they were keen to avoid war.


title: Berlin Blockade

text: In 2007, Tegel was joined by a re-developed Berlin-Schönefeld International Airport in Brandenburg. As a result of the development of these two airports, Tempelhof was closed in October 2008, while Gatow became home of the Bundeswehr Museum of Military History – Berlin-Gatow Airfield and a housing development. In October 2020, the expansion of Schönefeld into the larger Berlin Brandenburg Airport was completed, making Tegel mostly redundant as well.


title: Berlin Blockade

text: In the early days, the Americans used their C-47 Skytrain or its civilian counterpart Douglas DC-3. These machines could carry a payload of up to 3.5 tons, but were replaced by C-54 Skymasters and Douglas DC-4s, which could carry up to 10 tons and were faster. These made up a total of 330 aircraft, which made them the most used types. Other American aircraft such as the five C-82 Packets, and the one YC-97A Stratofreighter , with a payload of 20 tons—a gigantic load for that time—were only sparsely used.


title: Berlin Blockade

text: The British used a considerable variety of aircraft types. Many aircraft were either former bombers or civil versions of bombers. In the absence of enough transports, the British chartered many civilian aircraft. British European Airways (BEA) coordinated all British civil aircraft operations. Apart from BEA itself, the participating airlines included British Overseas Airways Corporation (BOAC) and most British independent airlines of that era—e.g. Eagle Aviation, Silver City Airways, British South American Airways (BSAA), the Lancashire Aircraft Corporation, Airwork, Air Flight, Aquila Airways, Flight Refuelling Ltd (which used their Lancaster tankers to deliver aviation fuel), Skyways, Scottish Airlines and Ciro's Aviation.


title: Fear Street Part Two: 1978

text: Fear Street Part Two: 1978 (titled onscreen as Fear Street 1978) is a 2021 American teen supernatural slasher film directed by Leigh Janiak, with a script co-written by Janiak and Zak Olkewicz, from an original story by Janiak, Olkewicz and Phil Graziadei. Based on the book series of the same name by R. L. Stine, it is the second installment in the "Fear Street" trilogy after "" and stars Sadie Sink, Emily Rudd, Ryan Simpkins, McCabe Slye, Ted Sutherland, Gillian Jacobs, Kiana Madeira, Benjamin Flores Jr. and Olivia Scott Welch. The film centers on a group of teenagers in Camp Nightwing who must come together to survive a possessed counselor's murder spree.


title: Fear Street Part Two: 1978

text: Produced by Chernin Entertainment, a film adaptation of "Fear Street" began development at 20th Century Fox in 2015, with Janiak hired in 2017. Filming for the trilogy took place back-to-back from March to September 2019 in Georgia, with the intention of a theatrical release beginning June 2020. However, due to the COVID-19 pandemic and the acquisition of 21st Century Fox by Disney, Chernin Entertainment ended their distribution deal with 20th Century Studios and sold rights to Netflix in August 2020.


title: Fear Street Part Two: 1978

text: "Fear Street Part Two: 1978" premiered at the Los Angeles State Historic Park on July 8, 2021, and was released by Netflix on July 9, 2021. The film received generally positive reviews from critics, who praised the screenplay, direction and the performances of Sink, Rudd and Simpkins. The final installment in the trilogy, "", was released on July 16.


title: Fear Street Part Two: 1978

text: In 1994, Deena and Josh Johnson restrain Sam, Deena's girlfriend who is possessed, and travel to C. Berman's house for help. Initially reluctant, Berman allows them inside and begins recounting the events of the Camp Nightwing massacre.


title: Fear Street Part Two: 1978

text: On July 19, 1978, Ziggy Berman from Shadyside is accused of stealing by Sheila, a Sunnyvale camper, and her friends. They accuse her of being a witch and in retaliation, hang her from a tree and burn her arm with a lighter before camp counselors Nick Goode and Kurt intervene. Ziggy's older sister, Cindy, and her boyfriend Tommy Slater are cleaning the mess hall when Nurse Lane, the mother of Ruby Lane, attacks Tommy, but he overpowers her and she is later removed from camp by police. The teenagers from Sunnyvale believe she was possessed by Sarah Fier, as was her daughter. While investigating the infirmary, Cindy and Tommy encounter counselors Alice, Cindy's former friend, and her boyfriend Arnie. They find Lane's diary which says that Fier made a deal with the devil by cutting off her hand on Satan's stone, thereby earning eternal life. They also find a map in the diary leading to Fier's house.


title: Fear Street Part Two: 1978

text: At the house, they find empty graves dug up by Nurse Lane and discover the witch's mark below the house. Alice and Cindy find a wall carved with the names of all the Shadyside killers and Tommy's name included. Tommy, now possessed, kills Arnie with an axe, and the girls escape into a cave. At camp, Nick helps Ziggy prank Sheila and lock her in the outhouse. As the two bond and share a kiss, Tommy reaches the camp and murders several Shadyside campers, including counselor Joan. Meanwhile, Cindy and Alice try to escape using the witch's mark in the diary as a map of the cave. They soon come across a pile of beating organs and when Alice touches it, it shows her flashbacks of all the past killers and their victims. After Alice injures her leg, she reconciles with Cindy and the two reach a cave opening beneath the outhouse.


title: Fear Street Part Two: 1978

text: After fighting an angry Sheila and knocking her unconscious, Ziggy and counselor Gary try to rescue Alice and Cindy until Tommy decapitates Gary. Ziggy hides with Nick until he is injured by Tommy and escapes to the mess hall. As the rest of the camp leaves via bus, Cindy finds a route to the mess hall while Alice stays behind. Tommy attacks Ziggy, but Cindy intervenes and kills him. Alice arrives and tells them that she found the witch's hand. She had started bleeding and realized that she was sitting near Satan's stone, where she dug it out.


title: Fear Street Part Two: 1978

text: The trio decides to end the curse by reuniting Sarah's hand with the body. Ziggy suddenly bleeds on the hand and sees a vision of Sarah Fier. This triggers the curse, resurrecting several Shadyside killers. A reanimated Tommy kills Alice before Cindy decapitates him. Ziggy and Cindy run to the tree where Fier was hanged, with the Shadyside killers in pursuit. They dig around the tree, only to find a rock with the words “The witch forever lives” carved. When Cindy realizes the killers are after Ziggy, she drops the hand and sacrifices herself. The two are murdered and the killers disappear. Nick later finds them and saves Ziggy via CPR.


title: Fear Street Part Two: 1978

text: Back in 1994, Deena and Josh realize that C. Berman is Ziggy, whose real name is Christine. They tell her that they found the witch's body and now, with the hand, they can end the curse. Deena and Josh go to Shadyside Mall, which was built after the closure of Camp Nightwing, and dig out the hand from under the same tree. They take it to the place where the body is buried and Deena reunites the body with the hand. Deena's nose bleeds and she finds herself back in 1666, where she is now Sarah Fier.


title: Fear Street Part Two: 1978

text: On October 9, 2015, it was announced that a film based on Stine's "Fear Street" series was being developed by 20th Century Studios (then known as 20th Century Fox before its acquisition by Disney) and Chernin Entertainment. Screenwriter Zak Olkewicz was hired to write the script for the second film while Kyle Killen and Silka Lusia were assigned to "Part One" and "Part Three" respectively. In July 2017, Leigh Janiak was hired to lead the project, directing and rewriting the films. Janiak oversaw a writers room with her writing partner, Phil Graziadei. In January 2019, Alex Ross Perry was slated to direct the second installment. By March of that year, Perry stepped down, and Janiak was confirmed as directing all three films, a trilogy set in different time periods, and shot back-to-back, with the intention of releasing the films one month apart.


title: Fear Street Part Two: 1978

text: In April 2019, Gillian Jacobs, Sadie Sink, Emily Rudd and McCabe Slye joined the cast. In March 2019, filming had begun on the first film in Atlanta and East Point, Georgia. Production also took place at Hard Labor Creek State Park in Rutledge in August 2019. Despite being the second film of the trilogy, "1978" was the last of the three films to be shot. Filming wrapped in September 2019.


title: Fear Street Part Two: 1978

text: The first film of the trilogy was scheduled to be released theatrically in June 2020, but it was pulled from the schedule because of the COVID-19 pandemic. In April 2020, Chernin Entertainment ended their distribution deal with 20th Century Studios and made a multi-year first-look deal with Netflix. By August 2020, Netflix had acquired the distribution rights to the "Fear Street" trilogy. The film premiered at the Los Angeles State Historic Park on July 8, 2021 before it was released on Netflix on July 9, 2021.


title: Fear Street Part Two: 1978

text: On the review aggregator website Rotten Tomatoes, the film holds an approval rating of based on reviews, with an average rating of . The website's critics consensus states, "A smart and subversive twist on slasher horror, "Fear Street Part II: 1978" shows that summer camp has never been scarier thanks to stellar performances from Sadie Sink, Emily Rudd, and Ryan Simpkins." According to Metacritic, which assigned a weighted average score of 61 out of 100 based on 16 critics, the film received "generally favorable reviews."


title: Fear Street Part Two: 1978

text: Natalia Winkelman, in her review of the "Fear Street" trilogy for "The New York Times", described "1978" as being the strongest film in the trilogy, and wrote: "the change in scenery ensures that "Part Two" never feels like a clone of "Part One."" Writing for "Empire", Ian Freer gave the film a score of 3 stars out of 5, writing: "It might not work as well as "Part One: 1994", but it cements the idea that telling a narrative in feature-length instalments ... can be a fruitful mode for ambitious long-form storytelling", but stated: "As the plot splits the teens up, there is little of the engaging interplay between the friends of the first part and, with only one type of maniac on the loose, the kills themselves feel same-y, less imaginative."


title: Fear Street Part Two: 1978

text: Lovia Gyarkye of "The Hollywood Reporter" described the film as being "its own exhilarating adventure that showcases a dynamic cast of characters and revels in lots and lots of bloody murder." She concluded: "For me, the best parts of "Fear Street Part 2" are the ones in which the teen drama takes center stage — from the illicit romantic pairings to the crazy feuds and pranks. Genre purists will be relieved that none of that comes at the expense of grisly murder scenes; Janiak spares no one, and there’s no shortage of inventive deaths." Kevin Maher of "The Times" gave the film a score of 3 stars out of 5, writing: "As with the first outing, the director Leigh Janiak proves herself an impeccable stylist, delivering muted 1970s tones, judiciously judged scares and ceaseless tap-a-long tunes".


title: Fear Street Part Two: 1978

text: Nick Allen of "RogerEbert.com" gave the film a score of 2 out of 4 stars. He wrote that the "hacking is top-notch", and praised the score by Marco Beltrami and Brandon Roberts, but concluded that the film is "a frustrating bummer—a summer camp slasher that’s afraid of campiness, and one that’d be a better fit for group therapy sessions than sleepovers." Barry Hertz of "The Globe and Mail" wrote: "While Part One stands as a fine-enough ode to the slasher renaissance of the mid-1990s ... Part Two proves that the entire "Fear Street" enterprise could have easily kept its time-hopping ambitions to a two-hour kill fest", adding: "the big and bloody problem with Part Two is that, by making a horror flick set at a 1970s summer camp with a contemporary perspective and budget, director Leigh Janiak has set herself up for failure."


title: San Mateo, California

text: San Mateo ( ; ) is a city in San Mateo County, California, on the San Francisco Peninsula. About 20 miles (32 km) south of San Francisco, the city borders Burlingame to the north, Hillsborough to the west, San Francisco Bay and Foster City to the east and Belmont to the south. The population was 105,661 at the 2020 census.


title: San Mateo, California

text: San Mateo has a Mediterranean climate and is known for its rich history at the center of the San Francisco Bay Area. Some of the biggest economic drivers for the city include technology, health care and education.


title: San Mateo, California

text: The Ramaytush people lived in the land, prior to its becoming the city of San Mateo. In 1789, the Spanish missionaries had named a Native American village along Laurel Creek as "Los Laureles" or the Laurels (Mission Dolores, 1789). At the time of Mexican Independence, 30 native Californians were at San Mateo, most likely from the Salson tribelet.


title: San Mateo, California

text: Captain Frederick William Beechey in 1827 traveling with the hills on their right, known in that part as the Sierra del Sur, began to approach the road, which passing over a small eminence, opened out upon "a wide country of meadow land, with clusters of fine oak free from underwood... It strongly resembled a nobleman's park: herds of cattle and horses were grazing upon the rich pasture, and numerous fallow‑deer, startled at the approach of strangers, bounded off to seek protection among the hills... This spot is named San Matheo, and belongs to the mission of San Francisco."


title: San Mateo, California

text: Starting in 1856, the city of San Mateo was documented by Spanish colonists as part of the Rancho de las Pulgas (literally "Ranch of the Fleas") and the Rancho San Mateo, the earliest history is held in the archives of Mission Dolores.


title: San Mateo, California

text: Around the 1850s, some San Franciscans began building summer homes in the mid-Peninsula, because of the milder climate. While most of this early settlement occurred in adjacent Hillsborough and Burlingame, a number of historically important mansions and buildings were constructed in San Mateo.


title: San Mateo, California

text: A.P. Giannini, founder of the Bank of Italy (which later became the Bank of America), lived here most of his life. His mansion, Seven Oaks, is listed in the National Register of Historic Places (No. 99001181). Located at 20 El Cerrito Avenue, it has been deteriorating as it has not been preserved or occupied for years.


title: San Mateo, California

text: In 1858, Sun Water Station, a stage station of the Butterfield Overland Mail route, was established in San Mateo. It was located south of Clarks Station in what is now San Bruno and 9 miles north of the next station at Redwood City.


title: San Mateo, California

text: The Howard Estate was built in 1859 on the hill accessed by Crystal Springs Road. The Parrott Estate was erected in 1860 in the same area, giving rise to two conflicting names for the hill, Howard Hill and Parrot Hill. After use of the automobile changed traffic patterns, neither historic name was commonly applied to that hill. The Borel Estate was developed near Borel Creek in 1874. It has been redeveloped since the late 20th century for use as modern offices and shops. The property is managed and owned by Borel Place Associates and the Borel Estate Company.


title: San Mateo, California

text: Hayward Park, the 1880 American Queen Anne-style residence of Alvinza Hayward (often said to be "California's first millionaire" from his silver and banking fortunes), was built on an estate in San Mateo which included a deer park and racetrack, roughly bounded by present-day El Camino Real (on the west), 9th Avenue (on the north), B Street (on the east) and 16th Avenue (on the south). A smaller portion of the property and the mansion, was converted into The Peninsula Hotel in 1908, following Hayward's death in 1904. The hotel burned down in a spectacular fire on 25 June 1920.


title: San Mateo, California

text: In 1893, Pedro Evencio had been called the last of the Ramaytush Native American of San Mateo. However his descendant, Joseph (José) Evencio (the younger) lived at Coyote Point until World War II; his final whereabouts are unknown.


title: San Mateo, California

text: In the early 20th century, Japanese immigrants came to San Mateo to work in the salt ponds and flower industry. Although Japanese-Americans only account for 2.2% of the population today, they continue to be a major cultural influence and a draw for the rest of the region. The Eugene J. De Sabla Japanese Teahouse and Garden was established in 1894 at 70 De Sabla Road, designed by Makoto Hagiwara, designer of the Japanese garden in Golden Gate Park in San Francisco. He arranged for Japanese artisans to be brought to the United States primarily for its teahouse construction. The parcel was purchased in 1988 by San Francisco businessman Achille Paladini and wife Joan, who have restored it. The garden features hundreds of varieties of plants and several rare trees. A large koi pond surrounds an island. The property was placed on the National Register of Historic Places in 1992.


title: San Mateo, California

text: In December 1967, Sgt. Joe Artavia, then serving in Vietnam with Alpha Company, 1st Battalion, 327th Infantry Regiment of the 101st Airborne Division wrote to his sister, Linda Giese, who was a resident of San Carlos working in San Mateo, asking if San Mateo or San Francisco could adopt the company, saying that it would bring "the morale of the guys up as high as the clouds". San Mateo passed a resolution on March 4, 1968, officially adopting Alpha Company and letters and gifts began arriving from the citizens of San Mateo. Joe would be killed in action on March 24, 1968, less than three weeks after the resolution. Linda would travel to Vietnam to meet with the men of Alpha Company for Christmas in 1968 and deliver personalized medallions from the City of San Mateo. In 1972, San Mateo requested and received permission to have Alpha Company visit the city when they left Vietnam, later holding a parade in January 1972, believed to be the only parade honoring the military during the Vietnam War. In 1988, Joseph Brazan wrote a screenplay entitled "A Dove Among Eagles" chronicling the adoption of Alpha Company by San Mateo and the real-life romance between Linda and Artavia's commander, Lt. Stephen Patterson. The city expanded its support to the entire 1st Battalion in 1991, when they were deployed to Kuwait under Operation Desert Storm.


title: San Mateo, California

text: In the November 2022 election, Councilmember Diane Papan was elected to the California State Assembly, creating a vacancy on the 5-person City Council. At the December 5, 2022 council reorganization meeting, two of the remaining four councilmembers chose not to follow the standard precedent of selecting a new Mayor, which normally rotates to the councilmember who has been in office the longest. With the vote split at 2-2, the city went a week without a Mayor. After a second meeting that also ended without a decision, Amourence Lee was selected as the Mayor at the third meeting on December 12.


title: San Mateo, California

text: San Mateo is located at (37.554286, −122.313044). According to the United States Census Bureau, the city has a total area of , of which are land and , comprising 23.63%, are covered by water.


title: San Mateo, California

text: The best-known natural area is Coyote Point Park, a rock outcropped peninsula that juts out into the San Francisco Bay. The early Spanish navigators named it "la punta de San Mateo." Crews of American cargo ships carrying grain in the bay renamed it "Big Coyote". Sailors had a penchant for naming promontories at the edge of San Francisco Bay after the coyote; across the bay in Fremont are the Coyote Hills, part of Coyote Hills Regional Park. By the 1890s, the shore area was developed as a popular beach called San Mateo Beach. In 1842, the Spanish had named it "playa de San Mateo". Today, Coyote Point is home to CuriOdyssey, formerly known as the Coyote Point Museum, a major natural history museum and wildlife center in the state. The animal care facility for the Peninsula Humane Society is also situated at Coyote Point, where the adoption facility is located in Burlingame, CA.


title: San Mateo, California

text: The variety of natural habitats includes mixed oak woodland, riparian zones, and bayland marshes. One endangered species, the California clapper rail, was sighted feeding on mudflats by the Third Avenue bridge in San Mateo. The marsh areas are also likely habitat for the endangered salt marsh harvest mouse, which inhabits the middle and high zones of salt and brackish marshes, as well as for the endangered marsh plant, Point Reyes bird's beak.


title: San Mateo, California

text: Sugarloaf Mountain, whose name has been documented in 1870, is a prominent landform between the forks of Laurel Creek. In the late 20th century, this mixed oak woodland and chaparral habitat was a site of controversy related to proposals to develop a portion of the mountain for residential use. It has been preserved for use as park and open space area, and is home to the endangered mission blue butterfly.


title: San Mateo, California

text: Sawyer Camp Trail, located on the western edge of San Mateo along the Crystal Springs Reservoir, is another popular destination for joggers, pedestrians, and bikers. This roughly trail begins in San Mateo and stretches north toward Hillsborough and San Bruno, parallel to the 280 freeway.


title: San Mateo, California

text: San Mateo has a Mediterranean climate with warm, dry summers and mild, damp winters. The city is generally shielded from the Pacific Ocean by the Montara Mountain block of the Santa Cruz Mountains, but two gaps in the mountains (the San Bruno Gap, between Montara Mountain and San Bruno Mountain; and the Crystal Springs Gap, near where State Route 92 meets State Route 35, west of the College of San Mateo) can channel ocean weather, resulting in gusty afternoon winds that bring fog toward San Mateo in the late afternoon through early morning in the summer.


title: San Mateo, California

text: The National Weather Service maintained a cooperative weather station in San Mateo until 1978; records for the period show that January, the coolest month, had an average maximum of and an average minimum of , and September, the warmest month, had an average maximum of and an average minimum of . The record maximum temperature was on June 14, 1961, and the record minimum temperature was on January 5, 1949, and December 9, 1972. Annual precipitation averaged of rainfall, falling on an average of 60 days each year. The wettest year was in 1973 and the driest year was of rainfall in 1953. The most precipitation in one month was of rainfall in December 1955 and the most precipitation in 24 hours was of rainfall on December 23, 1955. Based on comparison with the existing NWS office at San Francisco International Airport, San Mateo is generally a few degrees warmer in summer than the airport and a few degrees cooler in winter, while annual precipitation is almost the same at the airport and in San Mateo. In recent years, daily temperature reports for San Mateo from local weather observers have been published in the "San Mateo Times" and the "San Francisco Chronicle".


title: San Mateo, California

text: The 2010 United States Census reported that San Mateo had a population of 97,207. The population density was . The racial makeup of San Mateo was 56,214 (46.8%) White, 2,296 (2.4%) African American, 505 (0.5%) Native American, 18,384 (18.9%) Asian (7.9% Chinese, 4.6% Filipino, 2.2% Japanese, 1.8% Indian, 0.8% Korean, 0.3% Vietnamese, 0.2% Thai), 1,998 (2.1%) Pacific Islander (1.2% Tongan, 0.3% Fijian, 0.2% Samoan, 0.1% Hawaiian), 12,264 (12.6%) from other races, and 5,546 (5.7%) from two or more races. Hispanic or Latino of any race were 25,815 persons (26.6%); 14.4% of San Mateo is Mexican, 2.8% Guatemalan, 2.6% Salvadoran, 1.2% Peruvian, 0.9% Nicaraguan, 0.5% Puerto Rican, 0.3% Colombian, 0.3% Chilean, 0.2% Honduran, and 0.2% Cuban.


title: San Mateo, California

text: The Census reported that 95,891 people (98.6% of the population) lived in households, 975 (1.0%) lived in non-institutionalized group quarters, and 341 (0.4%) were institutionalized.


title: San Mateo, California

text: There were 38,233 households, out of which 11,464 (30.0%) had children under the age of 18 living in them, 17,964 (47.0%) were opposite-sex married couples living together, 3,824 (10.0%) had a female householder with no husband present, 1,656 (4.3%) had a male householder with no wife present. There were 2,098 (5.5%) unmarried opposite-sex partnerships, and 343 (0.9%) same-sex married couples or partnerships. 11,751 households (30.7%) were made up of individuals, and 4,391 (11.5%) had someone living alone who was 65 years of age or older. The average household size was 2.51. There were 23,444 families (61.3% of all households); the average family size was 3.14.


title: San Mateo, California

text: The population was spread out, with 20,254 people (20.8%) under the age of 18, 6,915 people (7.1%) aged 18 to 24, 30,772 people (31.7%) aged 25 to 44, 25,286 people (26.0%) aged 45 to 64, and 13,980 people (14.4%) who were 65 years of age or older. The median age was 38.9 years. For every 100 females, there were 95.4 males. For every 100 females age 18 and over, there were 92.8 males.


title: San Mateo, California

text: There were 40,014 housing units at an average density of , of which 19,969 (52.2%) were owner-occupied, and 18,264 (47.8%) were occupied by renters. The homeowner vacancy rate was 1.5%; the rental vacancy rate was 3.7%. Of the population, 50,951 people (52.4%) lived in owner-occupied housing units and 44,940 people (46.2%) lived in rental housing units.


title: San Mateo, California

text: According to the 2011 American Community Survey 5-Year estimate, the median income for a household in the city was $86,772, and the median income for a family was $107,023. Males had a median income of $65,541 versus $60,491 for females. The per capita income for the city was $25,248. About 3.6% of families and 5.9% of the population were below the poverty line, including 6.1% of those under age 18 and 5.9% of those age 65 or over.


title: San Mateo, California

text: San Mateo is structured as a council–manager form of government. The City Council has five members elected every two years to staggered four-year terms. In 2022, the city began the process of switching from at-large elections to district elections.


title: San Mateo, California

text: According to the California Secretary of State, as of February 10, 2019, San Mateo has 54,946 registered voters. Of those, 27,502 (50.1%) are registered Democrats, 8,504 (15.5%) are registered Republicans, and 16,772 (30.5%) have declined to state a political party.


title: San Mateo, California

text: In general, San Mateo's downtown core and the neighborhoods east of El Camino Real are more populous and have a greater density than the neighborhoods to the west of El Camino Real, where there is a lower population density.


title: San Mateo, California

text: San Mateo has one of the larger, better-developed suburban downtowns in the San Francisco Bay Area. It is located roughly between Tilton Ave. to the northwest, 9th Ave. to the southeast, Delaware St. to the northeast and El Camino Real to the southwest. The downtown core contains over 800 shops and restaurants, many located in historic buildings from the late 19th and early 20th centuries. The non-profit Downtown San Mateo Association (DSMA) works on behalf of downtown businesses to promote them and improve the downtown area.


title: San Mateo, California

text: Central Park is considered to be San Mateo's signature park with a baseball field, tennis courts, sculptures, picnic areas, playground, Japanese tea garden, recreation center, miniature train, rose garden and the San Mateo Arboretum. The property was purchased by the city in 1922. A historically influential area for the Japanese-American community, the downtown is home to many Japanese restaurants and shops. A large, 12-screen movie theater complex is located off the Main Street alley between 2nd and 3rd Ave. The San Mateo Caltrain station is situated downtown. The area also contains many large and small multi-story office buildings, apartments, government buildings and Mills Medical Center.


title: San Mateo, California

text: Segments of South B Street between 1st and 3rd Ave. and the southbound lane between Baldwin and 1st Ave. were temporarily closed to vehicular traffic in 2020 to allow for expanded outdoor dining. The San Mateo City Council extended the temporary closure through the end of 2021 and voted in September 2021 to create a permanent pedestrian mall between 1st and 3rd Ave. The plan requires a fire lane in the center of the street for public safety vehicles and necessary garbage or delivery services. The city aims to conduct the project in two phases: First, by installing retractable bollards and updating traffic signals and signage, then by raising the level of the street to be flush with sidewalk and reimagining its landscaping.


title: San Mateo, California

text: Hillsdale Shopping Center is a mall in San Mateo County, featuring over 120 stores in the mall itself and surrounded by many big box stores. Tenants include anchors Nordstrom, Ethan Allen and Macy's. The construction of a new food court and the outdoor North Block Plaza expanded the mall in 2019. New entertainment additions include luxury movie theater Cinépolis and a Pinstripes bowling alley off El Camino Real. The Hillsdale Caltrain station is located across El Camino.


title: San Mateo, California

text: The Bay Meadows neighborhood is an mixed-use transit-oriented development on the site of the former Bay Meadows Racetrack, a horse racing venue that closed in 2008. The area includes hundreds of new residential units, office space, retail space and parks and a town square. Ground broke in 2012 and construction on various projects continues as of 2021.


title: San Mateo, California

text: The economy of San Mateo is considered very diverse with jobs in the technology, health care, financial services, government, and retail trade fields being among the most numerous. Current and former companies based in San Mateo include Sony Interactive Entertainment, NetSuite, Franklin Templeton Investments, Fisher Investments, Solstice, Guidewire Software, Coupa, Snowflake Inc., Roblox Corporation, Marketo, SurveyMonkey, Devsisters USA, and GoPro.


title: San Mateo, California

text: According to the city's 2021 Annual Comprehensive Financial Report, the top employers in the city are:


title: San Mateo, California

text: Since 1990, San Mateo has had a voter-approved ordinance limiting the height of new development to . The San Mateo housing market is one of the most expensive in the country. In February 2018, the median San Mateo home was valued at $1,463,900, and the median rent was ranked ninth in the entire nation, at $2,242 per month.


title: San Mateo, California

text: In the mid-2000s, the second stories of downtown San Mateo buildings became a hub for startup companies, including Roblox, GoPro and YouTube.


title: San Mateo, California

text: Residents are zoned for schools in the San Mateo Foster City School District and San Mateo Union High School District. Elementary schools comprise Preschool, K-5, Middle and Magnet schools. There is a private, PreK-8 school: Saint Matthew's Episcopal Day School There are three public high schools: San Mateo, Aragon, and Hillsdale. There are also three private high schools: one all-male Catholic high school, Junípero Serra; one all-female Catholic high school, Notre Dame; and the Nueva Upper School. There is the Carey School.


title: San Mateo, California

text: The San Mateo Union High School District also hosts an adult school behind San Mateo High School. The San Mateo Performing Arts Center, one of the largest local theaters, is located on the San Mateo High School campus.


title: San Mateo, California

text: The city is home to the College of San Mateo, a community college. The campus of over 10,000 students is located on in the western foothills of the city which offer a panoramic view of the San Francisco Bay. Other universities in the area include Notre Dame de Namur University, a private Catholic university of 2,000 students in neighboring Belmont and Stanford University located about to the south.


title: San Mateo, California

text: The City of San Mateo operates three libraries within the city. The Main Library, the Hillsdale Library, and the Marina Library are all part of the Peninsula Library System. The Main Library located near Central Park in downtown opened in 2006 after residents passed a $30 million bond measure. Upon opening, the three-story, building earned numerous design awards and was LEED-certified NC Gold. Floor-to-ceiling windows provide abundant natural light. The technologically advanced building is modeled after a retail bookstore.


title: San Mateo, California

text: San Mateo maintains more than 15 parks throughout the city. Central Park is considered to be the main one and hosts many community park functions that serve downtown residents. It has a Japanese tea garden to commemorate sister city Toyonka, Japan. The park also features a rose garden, a mini train and the San Mateo Arboretum.


title: San Mateo, California

text: Beresford Park is another large park that offers bocce ball and a skate plaza. Martin Luther King Jr. Park and Joinville Park offer swimming pools, while Ryder Park boasts a water play structure. Parkside Aquatic Park, located on Seal Slough, has beach swimming and volleyball. Many of these parks have picnic areas with grills, children's play areas, basketball and tennis courts, and baseball diamonds.


title: San Mateo, California

text: Coyote Point Park, near the border with Burlingame and on the San Francisco Bay, is a regional county park known for its ideal location for windsurfing and sailing. It is also home to CuriOdyssey: a hands-on science museum and small native animal zoo.


title: San Mateo, California

text: Public art is located all around the city. One of the more memorable works is the large, brightly colored 1963 mosaic mural designed by Louis Macouillard and constructed by Alfonso Pardiñas. The mural is located in front of a mid-century-modern-style Bank of America branch at 300 S. El Camino Real and tells the story of A. P. Giannini, who founded the bank as the Bank of Italy.


title: San Mateo, California

text: San Mateo is considered to be near the center of the San Francisco Bay Area about halfway between San Francisco and San Jose, the region's two largest cities. It is served by three major freeways, including U.S. Route 101, Interstate 280, and State Route 92. State Route 92 east of San Mateo traverses the San Francisco Bay as the San Mateo-Hayward Bridge to the city of Hayward on its eastern shore.


title: San Mateo, California

text: San Mateo has a network of bikeways connecting major destinations in the city. In 2011, the city approved a Bicycle Master Plan to establish bicycling goals, identify gaps in the existing bikeway system, and create a prioritized list of infrastructure improvement projects.


title: San Mateo, California

text: SamTrans provides local bus service within the city of San Mateo as well as the entire county of San Mateo. AC Transit provides transbay bus service via the San Mateo Bridge to Alameda County. Caltrain provides commuter rail service on the San Francisco Peninsula between San Francisco and San Jose. Caltrain operates three stations within the city of San Mateo with stations at (serving the mall and surrounding area), (near Highway 92), and (in downtown San Mateo). There are 41 northbound and 41 southbound trains with a stop in the city each weekday and 18 trains in both directions on weekends. Extra southbound trains are run to accommodate passengers after San Francisco Giants games. See public transportation in San Mateo County for more details.


title: San Mateo, California

text: San Mateo is located near three major airports, including San Francisco International Airport to the north. Oakland International Airport and San Jose Mineta International Airport are also within a half-hour drive. San Carlos Airport is a general aviation airport located about to the south.


title: San Mateo, California

text: Hospitals in San Mateo include the San Mateo Medical Center, an acute-care facility operated by the County of San Mateo. Cemeteries include Skylawn Memorial Park and St. John's Cemetery.


title: San Mateo, California

text: The College of San Mateo hosts a year-round Saturday-morning farmers' market for visitors and San Mateo residents alike, at 1700 W Hillsdale Blvd. The market is operated by the Pacific Coast Farmers' Market Association and has over 100 farmers, hot-food vendors, and artisans from around the San Francisco Bay Area.


title: Wet-bulb temperature

text: The wet-bulb temperature (WBT) is the temperature read by a thermometer covered in water-soaked (water at ambient temperature) cloth (a wet-bulb thermometer) over which air is passed. At 100% relative humidity, the wet-bulb temperature is equal to the air temperature (dry-bulb temperature); at lower humidity the wet-bulb temperature is lower than dry-bulb temperature because of evaporative cooling.


title: Wet-bulb temperature

text: The wet-bulb temperature is defined as the temperature of a parcel of air cooled to saturation (100% relative humidity) by the evaporation of water into it, with the latent heat supplied by the parcel. A wet-bulb thermometer indicates a temperature close to the true (thermodynamic) wet-bulb temperature. The wet-bulb temperature is the lowest temperature that can be reached under current ambient conditions by the evaporation of water only.


title: Wet-bulb temperature

text: Even heat-adapted people cannot carry out normal outdoor activities past a wet-bulb temperature of , equivalent to a heat index of . The theoretical limit to human survival for more than a few hours in the shade, even with unlimited water, is a wet-bulb temperature of – equivalent to a heat index of .


title: Wet-bulb temperature

text: If a thermometer is wrapped in a water-moistened cloth, it will behave differently. The drier and less humid the air is, the faster the water will evaporate. The faster water evaporates, the lower the thermometer's temperature will be relative to air temperature.


title: Wet-bulb temperature

text: Water can evaporate only if the air around it can absorb more water. This is measured by comparing how much water is in the air to the maximum that could be in the air—the relative humidity. 0% means the air is completely dry, and 100% means the air contains all the water it can hold in the present circumstances and it cannot absorb any more water (from any source).


title: Wet-bulb temperature

text: This is part of the cause of apparent temperature in humans. The drier the air, the more moisture it can take up beyond what is already in it, and the easier it is for extra water to evaporate. The result is that sweat evaporates more quickly in drier air, cooling down the skin faster. If the relative humidity is 100%, no water can evaporate, and cooling by sweating or evaporation is not possible.


title: Wet-bulb temperature

text: When relative humidity is 100%, a wet-bulb thermometer can also no longer be cooled by evaporation, so it will read the same as an unwrapped thermometer.


title: Wet-bulb temperature

text: The wet-bulb temperature is the lowest temperature that may be achieved by evaporative cooling of a water-wetted, ventilated surface.


title: Wet-bulb temperature

text: By contrast, the dew point is the temperature to which the ambient air must be cooled to reach 100% relative humidity assuming there is no further evaporation into the air; it is the temperature where condensation (dew) and clouds would form.


title: Wet-bulb temperature

text: For a parcel of air that is less than saturated (i.e., air with less than 100 percent relative humidity), the wet-bulb temperature is lower than the dry-bulb temperature, but higher than the dew point temperature. The lower the relative humidity (the drier the air), the greater the gaps between each pair of these three temperatures. Conversely, when the relative humidity rises to 100%, the three figures coincide.


title: Wet-bulb temperature

text: For air at a known pressure and dry-bulb temperature, the thermodynamic wet-bulb temperature corresponds to unique values of the relative humidity and the dew point temperature. It therefore may be used for the practical determination of these values. The relationships between these values are illustrated in a psychrometric chart.


title: Wet-bulb temperature

text: Lower wet-bulb temperatures that correspond with drier air in summer can translate to energy savings in air-conditioned buildings due to:


title: Wet-bulb temperature

text: The thermodynamic wet-bulb temperature is the temperature a volume of air would have if cooled adiabatically to saturation by evaporation of water into it, all latent heat being supplied by the volume of air.


title: Wet-bulb temperature

text: The temperature of an air sample that has passed over a large surface of liquid water in an insulated channel is the thermodynamic wet-bulb temperature—the air has become saturated by passing through a constant-pressure, ideal, adiabatic saturation chamber.


title: Wet-bulb temperature

text: Meteorologists and others may use the term "isobaric wet-bulb temperature" to refer to the "thermodynamic wet-bulb temperature". It is also called the "adiabatic saturation temperature", though meteorologists also use "adiabatic saturation temperature" to mean "temperature at the saturation level", i.e. the temperature the parcel would achieve if it expanded adiabatically until saturated.


title: Wet-bulb temperature

text: The thermodynamic wet-bulb temperature is a thermodynamic property of a mixture of air and water vapor. The value indicated by a simple wet-bulb thermometer often provides an adequate approximation of the thermodynamic wet-bulb temperature.


title: Wet-bulb temperature

text: For an accurate wet-bulb thermometer, "the wet-bulb temperature and the adiabatic saturation temperature are approximately equal for air-water vapor mixtures at atmospheric temperature and pressure. This is not necessarily true at temperatures and pressures that deviate significantly from ordinary atmospheric conditions, or for other gas–vapor mixtures."


title: Wet-bulb temperature

text: Wet-bulb temperature is measured using a thermometer that has its bulb wrapped in cloth—called a "sock"—that is kept wet with distilled water via wicking action. Such an instrument is called a "wet-bulb thermometer." A widely used device for measuring wet- and dry-bulb temperature is a "sling psychrometer", which consists of a pair of mercury bulb thermometers, one with a wet "sock" to measure the wet-bulb temperature and the other with the bulb exposed and dry for the dry-bulb temperature. The thermometers are attached to a swivelling handle, which allows them to be whirled around so that water evaporates from the sock and cools the wet bulb until it reaches thermal equilibrium.


title: Wet-bulb temperature

text: An actual wet-bulb thermometer reads a temperature that is slightly different from the thermodynamic wet-bulb temperature, but they are very close in value. This is due to a coincidence: for a water-air system the psychrometric ratio (see below) happens to be close to 1, although for systems other than air and water they might not be close.


title: Wet-bulb temperature

text: To understand why this is so, first consider the calculation of the thermodynamic wet-bulb temperature.


title: Wet-bulb temperature

text: In this case, a stream of unsaturated air is cooled. The heat from cooling that air is used to evaporate some water which increases the humidity of the air. At some point the air becomes saturated with water vapor (and has cooled to the thermodynamic wet-bulb temperature). In this case we can write the following balance of energy per mass of dry air:


title: Wet-bulb temperature

text: For the case of the wet-bulb thermometer, imagine a drop of water with unsaturated air blowing over it. As long as the vapor pressure of water in the drop (function of its temperature) is greater than the partial pressure of water vapor in the air stream, evaporation will take place. Initially, the heat required for the evaporation will come from the drop itself since the fastest moving water molecules are most likely to escape the surface of the drop, so the remaining water molecules will have a lower average speed and therefore a lower temperature.


title: Wet-bulb temperature

text: Instead, as the drop starts cooling, it is now colder than the air, so convective heat transfer begins to occur from the air to the drop. Furthermore, the evaporation rate depends on the difference of concentration of water vapor between the drop-stream interface and the distant stream (i.e. the "original" stream, unaffected by the drop), and on a convective mass transfer coefficient, which is a function of the components of the mixture (i.e. water and air).


title: Wet-bulb temperature

text: After a certain period, an equilibrium is reached: the drop has cooled to a point where the rate of heat carried away in evaporation is equal to the heat gain through convection. At this point, the following balance of energy per interface area is true:


title: Wet-bulb temperature

text: Now let's go back to our original "thermodynamic wet-bulb" experiment, Experiment 1. If the air stream is the same in both experiments (i.e. formula_3 and formula_5 are the same), then we can equate the right-hand sides of both equations:


title: Wet-bulb temperature

text: If formula_25 then the temperature of the drop in Experiment 2 is the same as the wet-bulb temperature in Experiment 1. Due to a coincidence, for the mixture of air and water vapor this is the case, the ratio (called "psychrometric ratio") being close to 1.


title: Wet-bulb temperature

text: Experiment 2 is what happens in a common wet-bulb thermometer, meaning that its reading is fairly close to the thermodynamic ("real") wet-bulb temperature.


title: Wet-bulb temperature

text: In practice the value reported by a wet-bulb thermometer differs slightly from the thermodynamic wet-bulb temperature because:


title: Wet-bulb temperature

text: At relative humidities below 100 percent, water evaporates from the bulb, cooling it below ambient temperature. To determine relative humidity, ambient temperature is measured using an ordinary thermometer, better known in this context as a dry-bulb thermometer. At any given ambient temperature, less relative humidity results in a greater difference between the dry-bulb and wet-bulb temperatures; the wet-bulb is colder. The precise relative humidity is determined by reading from a psychrometric chart of wet-bulb versus dry-bulb temperatures, or by calculation.


title: Wet-bulb temperature

text: A wet-bulb thermometer can also be used outdoors in sunlight in combination with a "globe thermometer" (which measures the incident radiant temperature) to calculate the Wet Bulb Globe Temperature (WBGT).


title: Wet-bulb temperature

text: The "adiabatic wet-bulb temperature" is the temperature a volume of air would have if cooled adiabatically to saturation and then compressed adiabatically to the original pressure in a moist-adiabatic process (AMS Glossary). Such cooling may occur as air pressure reduces with altitude, as noted in the article on lifted condensation level.


title: Wet-bulb temperature

text: As the value referred to as "thermodynamic wet-bulb temperature" is also achieved via an adiabatic process, some engineers and others may use the term "adiabatic wet-bulb temperature" to refer to the "thermodynamic wet-bulb temperature". As mentioned above, meteorologists and others may use the term "isobaric wet-bulb temperature" to refer to the "thermodynamic wet-bulb temperature".


title: Wet-bulb temperature

text: "The relationship between the isobaric and adiabatic processes is quite obscure. Comparisons indicate, however, that the two temperatures are rarely different by more than a few tenths of a degree Celsius, and the adiabatic version is always the smaller of the two for unsaturated air. Since the difference is so small, it is usually neglected in practice."


title: Wet-bulb temperature

text: The wet-bulb depression is the difference between the dry-bulb temperature and the wet-bulb temperature. If there is 100% humidity, dry-bulb and wet-bulb temperatures are identical, making the wet-bulb depression equal to zero in such conditions.


title: Wet-bulb temperature

text: Living organisms can survive only within a certain temperature range. When the ambient temperature is excessive, many animals cool themselves to below ambient temperature by evaporative cooling (sweat in humans and horses, saliva and water in dogs and other mammals); this helps to prevent potentially fatal hyperthermia due to heat stress. The effectiveness of evaporative cooling depends upon humidity; wet-bulb temperature, or more complex calculated quantities such as wet-bulb globe temperature (WBGT) which also takes account of solar radiation, give a useful indication of the degree of heat stress, and are used by several agencies as the basis for heat stress prevention guidelines.


title: Wet-bulb temperature

text: A sustained wet-bulb temperature exceeding is likely to be fatal even to fit and healthy people, unclothed in the shade next to a fan; at this temperature human bodies switch from shedding heat to the environment, to gaining heat from it. In practice, such ideal conditions for humans to cool themselves will not always existhence the high fatality levels in the 2003 European and 2010 Russian heat waves, which saw wet-bulb temperatures no greater than 28 °C.


title: Wet-bulb temperature

text: A 2015 study concluded that depending on the extent of future global warming, parts of the world could become uninhabitable due to deadly wet-bulb temperatures. A 2020 study reported cases where a wet-bulb temperature had already occurred, albeit too briefly and in too small a locality to cause fatalities.