Operation Flax

Operation Flax was a Western Allied air operation executed during the Tunisian campaign, as part of the larger North African campaign of the Second World War. The operation was designed to cut the air supply lines between Italy and the Axis armies in Tunis, Tunisia, in April 1943. The parallel Allied naval effort was Operation Retribution.
In November 1942, American and British forces landed in North Africa under Operation Torch. Allied thrusts overran Vichy French Morocco and Algeria and advanced into Tunisia. The danger for the Axis Powers was now apparent. The Allied forces advancing eastward and the British 8th Army advancing westward after the victory at the Second Battle of El Alamein, would trap and destroy the remaining Axis forces in North Africa. In response to the crisis, and the poor state of Axis forces, reinforcements for the German "Afrika Korps", Italian Army and "Luftwaffe" were dispatched by sea and air. These reinforcements duly staved off an immediate defeat in Tunisia, the last region still in Axis hands. The poor state of the roads and rail lines in Algeria meant that Allied forces faced difficult logistic challenges which enabled the Axis to prolong a defence. The inexperience of U.S. forces was also apparent at the Battle of the Kasserine Pass. Nevertheless, the growing number and experience of Allied forces squeezed the Axis toward the northern tip of Tunisia. The Royal Air Force (RAF) and Royal Navy operating from Malta took a heavy toll of Axis shipping. However, Axis supplies were still reaching the besieged "Afrika Korps" by air. By early April, large quantities of Axis manpower was also being evacuated by air. Although the Allies held air superiority by this time, "Luftwaffe" transports were operating with impunity during darkness.
In order to prevent this the Allied Air Forces—the RAF and the United States Army Air Forces (USAAF)—were ordered to conduct operations against Axis air power by day and night in order to prevent their resupply or withdrawal. Owing to bad weather and the need to gather intelligence, the operation, codenamed "Flax", did not begin until 5 April. Although the Axis put up determined resistance and large scale air battles took place, the Allied Air Forces succeeded in destroying the aerial link between Axis-held Sicily and Italy. During the course of the interdiction operation, an air battle known as the 18 April "Palmsonntag Massaker" ("Palm Sunday Massacre") took place, in which the German Junkers Ju 52 transport fleets suffered heavy losses over Cape Bon while evacuating "Heer" (German Army) forces escaping from the Allied ground offensive Operation Vulcan. The air operation continued until 27 April. The operation did great harm to Axis logistical support. Along with the attempted airlift during the Battle of Stalingrad, Operation Flax inflicted such grievous losses on the German transport fleets that they were unable to recover.
Background.
Strategic situation.
The Axis campaign in North Africa was characterised by a lack of consistent concentrated logistics support to their forces in the field. The failure was one of the primary reasons that "Generalfeldmarschall" (Field Marshal) Erwin Rommel could not win a decisive breakthrough against the British 8th Army throughout 1941–1942. Rommel, at points, had recognised Malta as a serious obstacle to Axis logistical lines between Axis-held Europe and their forces in North Africa. Malta lay across their lines of communication and, despite being under siege for two and a half years, it remained an active base for Allied naval and air forces to interdict Axis supply lines for much of this period. Yet Rommel failed to apply enough pressure on the "Oberkommando der Wehrmacht" (German High Command, OKW) to launch a planned invasion of the island, Operation Herkules. Although Malta became largely ineffective as an offensive base in mid 1942, later that same year the Allied offensive from Malta became increasingly effective. The Axis defeat at the Second Battle of El Alamein and the Allied landings, Operation Torch, in Western North Africa, threatened to crush the Axis from both East and West. The Germans responded by sending reinforcements to Africa through Vichy-held Tunisia, but by the start of 1943 they were suffering increasing shipping losses to Malta's forces. Some respite was won for the Axis when the Allies lost the "Run for Tunis" in part owing to rapid German reactions and the difficulty in supplying their armies through the poor Algerian infrastructure. By early 1943, the Axis had numerical superiority in aircraft; 690 to the Allies' 480.
But for the Axis, the interdiction campaign from Malta caused chronic supply shortages in Africa. By April 1943, the Allied armies had pushed the supply-starved Axis forces to the northern tip of Tunisia, near its capital Tunis. Despite the desperate situation, the OKW continued to send in significant reinforcement and supply tonnage to the besieged Axis forces by air. To prevent prolonged resistance, the Allies, now aware of the German supply timetables through the use of British Ultra, launched an aerial offensive to destroy this link. It was due to begin in the last week of March 1943, but bad weather over Tunisia meant that it could not begin until 5 April.
Axis supply situation.
The situation in the air, on land and at sea was gradually deteriorating. Axis supply ships had suffered heavy losses between Cape Bon and Sicily. A total of 67% of all losses were to Allied aircraft. Theo Osterkamp was appointed "Jagdfliegerführer Sizilien" (Fighter Leader Sicily) to fly over the area, nicknamed "Death Row", by Axis shipping. On 7 April 1943, the organisation was given 148 fighters for these operations. The "Luftwaffe" reorganised its forces in Tunisia as well. Hans Seidemann was appointed "Fliegerkorps Tunis" (Flying Corps Tunisia) with three commands, "Fliegerführer Tunis" (Flying Leader Tunis), "Mitte" (Middle) and "Gabès", after its headquarters' location. Siedmann had the equivalent of 12 "Gruppen" (12 Groups) and maintained around 300 fighters until mid-April. The German fighter defences also benefited from a rudimentary radar supported early-warning network.
"Generalmajor" (Major General) Ulrich Buchholz—"Geschwaderkommodore" (Wing Commander) of KGzbV 3—was appointed "Lufttransportführer II, Mittelmeer" (Air Transport Leader II, Mediterranean Sea) on 15 January 1943. His forces were organised under the Naples-based KGzbV N (N for "Neapel", or Naples) and the Trapani-based KGzbV S. KGzbV S had to make two missions a day, KGzbV S only one. The formations would be 80–120 aircraft strong. Operations were to be flown at only in altitude, arriving around noon in order to operate during the Allied "lunch" period. The units—operating mostly the Junkers Ju 52-brought in 90 tonnes daily and the giant Messerschmitt Me 323s brought some 30 tonnes with their smaller numbers. The logistical effort was made using Indian prisoners of war, who helped unload supplies. The operational method usually involved escort fighters picking up the formation en route. Only one fighter aircraft for every five transports was made available owing to various shortages. The Naples units were met near Trapani, and on the return leg fighters, including Bf 110 "Zerstörer", escorted them home. The end of the airlifts at Stalingrad and in the Kuban allowed the expansion of Axis transport aircraft to 185 by 10 March. By the beginning of April, it rose to 426. The force flew much needed ammunition and fuel to the Axis armies in Africa.
Allied plan.
James H. Doolittle commanding Northwest African Strategic Air Force (NASAF) was ordered to formulate an air interdiction campaign. He named it Operation Flax. Operation Flax called for Allied fighters to intercept the aerial convoys over the Sicily-Tunisia strait. Allied units were also briefed to carry out major offensive operations against Axis airfields in Tunisia and the overcrowded staging fields in Sicily. They were also ordered to carry out anti-shipping sweeps. Flax was an operation which was unlikely to work more than a few times, as shown by the relative impunity with which the surviving Axis air transports operated at night after the operation had begun. The flight time across the Strait of Sicily was so short that aerial interception could be made only with precise intelligence. The Germans understood this but did not know that their communications had been compromised and were being read by Allied intelligence. Ignorant of their intelligence leaks, they operated by day. Since their enemy had the option of flying by night, and the weather conditions were not ideal for interception operations, the Allies delayed the implementation of Operation Flax until the most German transport aircraft were in operation so that the blow would be as decisive as possible. Allied intelligence listened in to the Y-stations until they were sure they could strike.
The tactical plan included coordinated strikes on Axis airfields carried out by Boeing B-17 Flying Fortress groups to tie down Axis fighter groups. Medium bomber units operating the North American B-25 Mitchell would fly sweeps over the Gulf of Tunis. They were to be joined by Lockheed P-38 Lightning heavy fighters which were also detailed to sweep the area. The presence of the B-25s would allow the P-38s to operate in the area without raising the Axis suspicions. It would seem as if they were there to escort the B-25s, rather than their actual intention, to interdict Axis air transports. Supermarine Spitfire units would sweep the straits further north, catching any enemy aircraft that evaded the P-38s. More B-25 and B-17 units were detailed to strike at Sicilian airfields to catch transports on the ground. The USAAF 9th Air Force was detailed to send its Consolidated B-24 Liberator bomb groups against airfields in and around Naples in this capacity as well. On 2 April Doolittle's superiors, supreme commander of all Allied Air Forces in the Mediterranean, Arthur Tedder and commander of Allied Air Forces in Western North Arica Carl Spaatz, decided to wait for the next suitable window to launch the offensive.
Order of battle.
Allied.
The Allied order of battle involved all the major commands in the area at the time. The Supreme Allied Air Force Command was the Mediterranean Air Command (MAD) under Air Chief Marshal Arthur Tedder. Below the supreme command were the sector organisations, the Northwest African Air Forces (NAAF) commanded by Carl Spaatz. Directly subordinated to Spaatz was the Northwest African Strategic Air Force (NASAF) under James H. Doolittle. The second command was the operational/tactical force, the Northwest African Tactical Air Force (NATAF) under Air Marshal Arthur Coningham.
Axis.
Martin Harlinghausen commanded "Fliegerkorps" II (Air Corps II), which controlled "Luftwaffe" operations in Africa, as part of "Luftflotte" 2 (Air Fleet 2). Subordinate to "Fliegerkorps" II were seven different "Kampfgeschwader" (Bomber Wings), under direct command. Several "Jagdgeschwader" (Fighter Wings) were also on-call for support. The "Luftwaffe" had the following forces available in April 1943:
Theo Osterkamp commanded "Jagdfliegerführer Sizilien":
Commanded by Wolfgang von Wild:
Commanded by Hans Seidemann:
Commanded by Walter Hagen
"X. Fliegerkorps" under the command of Alexander Holle:
"Lufttransportführer II, Mittelmeer" (Commander, Air-Transport Mediterranean) commanded by Ulrich Buchholz:
American operations.
Closing the straits.
At 06:30 on 5 April, 26 P-38s of the U.S. 1st Fighter Group conducted a sweep over the Sicilian Strait. Meanwhile, 18 B-25s of the 321st Bomb Group, escorted by 32 P-38s of the 82nd Fighter Group, set out on a maritime interdiction operation. Six of the P-38s returned to base for unrecorded reasons. The B-25s claimed two ferries damaged and a destroyer sunk. One B-25 was shot down.
The 1st Group arrived over Cape Bon at 08:00. They reported contact with several formations of different types. They estimated 50–70 Ju 52s, 20 Bf 109s, four Fw 190s, six Ju 87s and a Fw 189 formed these flights. In fact, the German formation had only 31 Ju 52s, ten Bf 109s, six to seven Bf 110s, four Ju 87s and one Fw 190. The U.S. fighters attacked, and a large air battle developed. The 82nd Fighter Group also engaged. The 1st Fighter Group claimed 11 Ju 52s, two Ju 87s, two Bf 109s and the Fw 189 for two P-38s lost. The 82nd claimed seven Ju 52s, three Ju 87s, three Bf 109s, one Bf 110 and one Me 210 for four P-38s. U.S. losses are uncertain, and there was a significant amount of over-claiming. In fact, German losses amounted to 13–14 Ju 52s and about three fighters. Another source states the loss of 13 Ju 52s and two Bf 109s, from 5./JG 27. (The supposed Fw 189 was no doubt a mis-identified P-38.)
Bomber offensive.
Later, 18 B-17s from the 97th Bomb Group bombed Axis airfields at El Aounina. Two Me 323s, two Ju 52s and five Italian transports were destroyed. A second mission was flown to Sid Ahmed. Both raids were flown with Spitfire escorts. Only a few German fighters intercepted, without success. The bombers claimed one German fighter destroyed.
One hour later, 35 B-25s from the 310th Bomb Group and 18 P-38s from the 82nd Fighter Group raided Axis airfields in Sicily near Borizzo. Some 80–90 Axis aircraft were counted, poorly camouflaged and vulnerable. The attack achieved good results with fragmentation bombs. The attackers were intercepted by 15 Bf 109s, losing two B-25s. The bombers claimed three Bf 109s while the P-38s claimed two of the German fighters. The 301st Bomb Group attacked Milo airfield, claiming 52 destroyed on the ground. Actual Axis losses were 13 German and eight Italian aircraft destroyed with 11 German and 30 Italian aircraft damaged. Some 72 B-17s of the 99th Bomb Group bombed the airfield at Bocca di Falco. They claimed to have seen 100–150 aircraft, but the raid only destroyed four Axis aircraft and damaged several. Spitfires claimed two Bf 109s for two losses. Two sweeps by P-38 groups found nothing further.
The NASAF claimed 201 Axis aircraft destroyed including 40 in the air. German sources only list the loss of 14 Ju 52s in aerial combat and 11 Ju 52s and Me 323s on the ground with 67 damaged. Aside from combat aircraft, the British Official History concludes 27 German and three Italian transports were lost on 5 April.
Fighter offensive.
The Operation Flax attacks merged into the preparatory phase of the Sicilian Campaign as air attacks were also helping to erode air defences on the island. While Flax continued on a smaller scale, the emphasis was on fighter operations. On 10 April, Flax was renewed. Some 75 P-38s of the 1st Fighter Group intercepted 20 Italian Savoia-Marchetti SM.82 and around six Macchi C.200s. The battle resulted in 10 transports and two Italian fighters being shot down. Later that morning, 27 P-38s of the 82nd Fighter Group were escorting 18 B-25s of the 310th Bomb Group over Cape Bon when 30 Ju 52s were spotted with two Bf 110s, two Ju 87s and just three Ju 88s with them. At first, 11 P-38s stayed with the B-25s acting as escort, but then the bombers joined in, flying past the transports and firing on them using their gunners. Around 15 Bf 109s were scrambled from Tunisia to help the transports and they destroyed one P-38 and damaged three more. However, the Germans had already suffered heavy losses. One P-38 pilot was killed when he flew into a Bf 110 and some B-25s were shot up. The Americans claimed 25 victories. The Germans lost 10 Ju 52s, one Ju 88, one Bf 109 and one Bf 110. Some Ju 52s managed to ditch and their crews survived. A Spitfire patrol later shot down four more Ju 52s. It is likely the Bf 110s "spotted" in the formation were actually Me 210s from "Zerstörergeschwader" 1. RAF and USAAF units also downed a SG 2 Fw 190 on a ferry flight, and another from SKG 210. An SG 2 Hs 129 was also shot down while another Ju 88 from III./KG 77 was also shot down.
On 11 April, the 82nd ran into 20 Ju 52s, four Ju 88s, four Bf 110s and seven Bf 109s. The Americans claimed all of the Ju 52s and seven escorts. Actual German and Americans losses are unclear. In the afternoon, 20 of the 82nd ran into 30 unescorted Ju 52s. The transports fought back, losing only five and shooting down one P-38. Its pilot was killed. The day's total amounted to 17 Ju 52s, one SM.82 and two Bf 110s destroyed. The RAF had also been involved in the day's operations. No. 152 Squadron RAF sent 34 Spitfires to intercept 12 Ju 52s escorted by a handful of Bf 109s. Three Ju 52s were shot down for the loss of two Spitfires, both claimed by Wolfgang Tonne of I./JG 53. The German units reported no losses.
The day had been bad for the "Luftwaffe". Losses amounted to 18 Ju 52s; four belonged to III./KG.z.b.V 1. Raids by RAF Vickers Wellington bombers continued during the night. Ju 88 night fighters from NJG 2 downed two Wellingtons. The results of the raids are not known.
On 13 April, B-17s from the 97th and 301st Bomb Groups bombed Sicilian airfields at Castelvetrano and Trapani. The Italians lost 11 SM.82s destroyed and 16 damaged on the ground. At Trapani the Germans lost eight aircraft and 40 damaged for the loss of two B-17s to the island's fighter defences consisting of Bf 109s from JG 27. Battles over the airfields in the afternoon were inconclusive, costing the Axis one Ju 88 from II./KG 26 and the Allies a RAF Spitfire from No. 232 Squadron RAF. That night, air raids killed four German fighter pilots from I./JG 53 while two Ju 88s from II./NJG 2 and III./KG 76 were lost.
Desert Air Force operations.
Early sweeps.
On 12 April, the RAF Desert Air Force took command over most of the Operation Flax operations. The RAF used sea-looking radar, which was less effective than it could have been as the German formations flew low. The considerable ranges stretched the P-40s and Spitfires to the limit. The British spread their forces more thinly to maintain continuous coverage. However, on 16 April 13 Spitfires ran into a large formation of Axis aircraft. The Spitfires shot down seven SM.82s and a Bf 109 for the loss of two. German fighters claimed three Spitfires. One of the two confirmed victims was Wing Commander Ian "Widge" Gleed of No. 244 Wing RAF. Gleed was possibly the victim of a "Leutnant" Ernst-Wilhelm Reinert of "4 Staffel" JG 77. At the time of his death Gleed had 14 victories. This setback meant small operations were abandoned. From that point on missions consisted of three P-40 squadrons covered by one Spitfire squadron.
On 16 April, in a small-scale counter-attack, eight SchlG 10 Fw 190s escorted by 16 Bf 109s of JG 27 led an attack on Allied airfields near Souk el Khemis. They destroyed six A-20 Havoc bombers. The next day, 17 April, II./ZG 26 several Bf 110s were shot down by No. 260 Squadron RAF P-40s on offensive operations. In response to the counter-attack, the American 97th Bomb Group dispatched seven B-17s covered by 40 P-38s to bomb Palermo airfields. A large air battle developed when 30 Bf 110s and Bf 109s from ZG 26 and JG 27 intercepted. The Bf 110s attacked the bombers while the JG 27 Bf 109s tackled the escorts. The Germans claimed five bombers and one fighter for the loss of one Bf 109. Actual Allied losses are unknown.
Palm Sunday Massacre.
The patrols failed to intercept any formations of transports on the afternoon of 18 April. In the evening, the Ninth Air Force's 57th Fighter Group sent out all of its squadrons, including the 314th Fighter Squadron of the 324th Fighter Group, under its command. The 57th had already flown unproductive sorties in the afternoon. Still, 47 USAAF P-40s arrived in the sweep area with 12 Spitfires from No. 92 Squadron RAF. The Spitfires flew high cover at while the P-40s stayed at around . Soon enough, a large formation of 30 Ju 52s was reported by Allied pilots at an altitude of only , flying north east on a return flight. In total there were 65 Ju 52s, 16 Axis fighters and five Bf 110s. As the Allied fighters began their attacks, the passengers fired machine guns out of the Junkers' windows in desperation to fend off the attack. In the air battle that followed, six P-40s and a Spitfire were shot down. The Americans claimed 146 victories, which was later reduced to 58 or 59 Ju 52s, 14 Macchi C.202s and Bf 109s and two to four Bf 110s. Actual German losses were 24 Ju 52s along with 10 fighters. The German fighter casualties amounted to nine Bf 109s and one Bf 110. Some Italian fighters may also have been shot down. Along with the 24 Ju 52s destroyed, another 35 were damaged and managed to crash-land all along the Sicilian coastline. The battle became known as the "Palm Sunday Massacre".
Continuation of offensive.
The following day, No. 7 Wing SAAF shot down another 16 Italian SM.82s. The ease with which they caught fire led the Allied pilots to believe they were carrying precious fuel cargoes. Among those units involved were No. 54 Squadron SAAF, No. 2 Squadron SAAF. Another source gives Axis losses as 10 destroyed and four crash landed.
On 22 April, the South African No. 7 Wing sent out 36 P-40s which intercepted a well escorted Italian formation. The South Africans claimed 12 Ju 52s, two SM 79s, a Ju 87 towing a glider, a Reggiane Re.2001, two Bf 109s and a Ju 88 for the loss of five Spitfires and three P-40s. Known Axis losses were 12 SM.79s and a Macchi C.202; RAF Spitfires flying from Malta downed another two transports. Later, a flight made in daylight cost the Axis 16 or 17 Me 323 transports destroyed, plus a Macchi C.202, three German fighters and a Re-2001, when they were intercepted by 36 Australian, British and South African P-40s covered by South African, British and Polish Spitfire units. Four P-40s were lost and one Spitfire had to force land. The main combatants in the battles were No. 1 Squadron SAAF, No. 112 Squadron RAF, No. 450 Squadron RAAF, I./JG 27 and II./JG 27.
Göring ordered that no more transport flights be made. Albert Kesselring complained that this would deny the Axis forces vital supplies, and Göring once again permitted flights. This time they were to travel via Sardinia, but no more than 60–70 flights would be allowed per night; some 250 had been mounted daily before Flax. The transports also had to run the gauntlet of radar-equipped Bristol Beaufighters but these rarely were successful at intercepting them.
One last Allied effort was made by 70 B-24 Liberators, which bombed airfields around Bari in Italy. Some 54 German aircraft were destroyed and 13 damaged on the ground. The USAAF units claimed 50.
Aftermath.
The aerial operation had a considerable effect in strangling Axis logistics. The supplies reaching Axis units dwindled, and the Axis armies and air units remaining in Tunisia gradually ran out of fuel, ammunition and other supplies. Having lost most of its airbases, the "Luftwaffe" evacuated most of its units. By early May 1943, only the Italian fighter units and one German "Gruppe" (I. JG 77), remained as the Axis held on to a narrow strip of African coastline near Tunis. Allied air superiority was so overwhelming, that "Luftwaffe" personnel climbed into fighter fuselages, or squeezed into the cockpits of Bf 109s alongside the pilot rather than risk flying in transport aircraft. Most ground crew and pilots attempted to escape this way. Flying large numbers of personnel in one go and by transport was too dangerous; 16 personnel were killed in a crash on 29 or 30 April. The last transport missions were flown on 4 May, in which 117 tons of fuel and ammunition were brought in. Some supply drops were attempted (by II./"Kampfgeschwader 1"), but most of the remaining signals, "FlaK", transport and administrative staff left were captured when the campaign ended on 13 May 1943.