 out to attack, and be almost wiped out in the process. This was somewhat ironic given the fact that due to French paranoia about being attacked by German aircraft, during the Sitzkrieg, the Battle force had actually trained over German airspace at night.
Bomber Command itself soon fully joined in the action. With the immensely quick collapse of France, invasion seemed a clear and present danger. As its part in Battle of Britain, Bomber Command was assigned to pound the invasion barges and fleets assembling in the Channel ports. This was much less high profile than the battles of the Spitfires and Hurricanes of RAF Fighter Command, but still vital and dangerous work. From July 1940 to the end of the year, Bomber Command lost nearly 330 aircraft and over 1,400 aircrew killed, missing or PoW.
Bomber Command was also indirectly responsible, in part at least, for the switch of Luftwaffe attention away from Fighter Command to bombing civilian targets. A German bomber on a raid got lost due to poor navigation and bombed London. Churchill consequently ordered a retaliatory raid on the German capital of Berlin. The damage caused was minor, but the raid sent Hitler into a rage. He ordered the Luftwaffe to level British cities, thus precipitating the Blitz.
Like the United States Army Air Forces later in the war, Bomber Command had first concentrated on a doctrine of "precision" bombing in daylight. However, when several late 1939 raids were cut to pieces by the organised German defences, a switch to night attack tactics was forced upon the Command. The problems of enemy defences were then replaced with the problems of simply finding the target. It was common in the early years of the war for bombers relying on dead reckoning navigation to miss entire cities. Surveys of Bombing photographs and other sources published during August 1941 indicated that less than one bomb in ten fell within 5 miles of its intended target. One of the most urgent problems of the Command was thus to develop technical navigational aids to allow accurate bombing.
Many squadrons and personnel from Commonwealth and other European countries were distributed throughout Bomber Command. No. 6 Group, which was activated on 1 January 1943, was unique among Bomber Command groups, in that it was not an RAF unit; it was a Canadian unit attached to Bomber Command. At its peak strength, 6 Group consisted of 14 operational RCAF bomber squadrons, and 15 different squadrons served with the group. Apart from 6 Group, many individual Canadians served with British and other Commonwealth squadrons; by the end of the war, almost a quarter of Bomber Command's personnel were RCAF personnel.
No. 8 Group, also known as the Pathfinder Force, was activated on 15 August 1942. It was a critical part of solving the navigational problems referred to above. The navigational problems of Bomber Command were solved by two methods. One was the use of a range of increasingly sophisticated electronic aids to navigation and the other was the use of specialist Pathfinders. The technical aids to navigation took two forms. One was external radio navigation aids, as exemplified by Gee and the later highly accurate Oboe systems. The other was the centimetric navigation equipment H2S radar which was carried in the bombers. The Pathfinders were a group of elite, specially trained and experienced crews who flew ahead of the main bombing forces, and marked the targets with flares and special marker bombs. No. 8 Group controlled the Pathfinder squadrons.
By late 1941, RAF Bomber Command was regularly mounting raids by hundreds of aircraft.
Along with an increase in the size of the Command came a massive increase in the capability of the aircraft it was using. In 1942, the main workhorse aircraft of the later part of the war came into service. The Halifax and Lancaster made up the backbone of the Command, and had a longer range, higher speed and much greater bomb load than the earlier aircraft. The classic aircraft of the Pathfinders, the Mosquito, also made its appearance.
A prolonged offensive against 