'Carpetbagger' was a US programme of air operations to deliver matériel and messages to agents in German-occupied Europe, most especially France, the Low Countries and Italy (1943/45).

The operation was undertaken by the USAAF, and the first such mission was flown on 4 January 1944. At a time late in 1943, the 22^nd Anti-Submarine Squadron of Lieutenant General James H. Doolittle’s 8^th AAF was disbanded at RAF Alconbury, and its aircraft were then used as the equipment of the newly established 36^th and 406^th Bombardment Squadrons. After some shuffling of commands, these two squadrons were placed under the 801^st Bombardment Group (Provisional) at the beginning of 1944, and the first 'Carpetbagger' missions were carried out by this unit under the control of Major General William Donovan’s Office of Strategic Services.

In April 1944 the group moved to RAF Harrington, a more remote (and thus more secure) base and, one month later and in anticipation of the expected invasion of Europe, the group was expanded to a strength four squadrons for enhanced capabilities and to undertake some of the missions previously undertaken by Air Chief Marshal Sir Arthur Harris’s RAF Bomber Command. The two new units were the 788^th and 850^th Bombardment Squadrons.

During August 1944 the 801^st BG (Provisional) dropped the provisional part of its designation, and also took over the designations and men of the 492^nd Bombardment Group from RAF North Pickenham while remaining at RAF Harrington with what were now the 856^th, 857^th, 858^th and 859^th Bombardment Squadrons.

From January 1944 to the end of World War II in May 1945, the 801^st BG, working with the British Special Operations Executive and later the Special Forces Headquarters (SFHQ) in London, dropped spies and supplies to resistance forces in Belgium, France, Denmark, the Netherlands and Norway.

There was a gap in the group’s resistance-support operations between mid-September of 1944 and the end of December 1944, and during this time the 801^st BG undertook a two-week programme of fuel-delivery flights to continental depots as a means of aiding the logistic support required for the maintenance of the Allied forces' advance.

After this, three squadrons began to train for night bombing operations, while the 856^th BS participated in the recovery from the continent of Allied airmen who had either evaded capture or walked out of Switzerland after that country relaxed its internment policy. This undertaking was carried out mainly with Douglas C-47 Skytrain transport aircraft assigned to the group originally for insertion operations during the previous summer.

During December 1944 the 859^th BS was detached to the US 15^th AAF in the Mediterranean theatre, being allocated to the 2641^st Special Operations Group based at Brindisi in southern Italy. After completing its recovery mission, the 856^th BS resumed its 'Carpetbagger' role on a limited basis during the bad weather of the winter of 1945, while the 857^th and 858^th BSs participated in medium-altitude bombing from a time late in December 1944 to March 1945.

In the spring of 1945 'Carpetbagger' operations resumed once more, although not to the extent of the previous year. The 857^th BS was detached to the 91^st BG at RAF Bassingbourne at the end of March 1945, while the 856^th and 858^th BSs dropped small numbers of agents, lone agents and sabotage teams into Denmark, Germany, the Netherlands and Norway. Harrington-based operations ended at the end of April 1945, though a few special OSS missions, such as those returning dignitaries to formerly occupied countries, continued until the 801^st BG was disbanded and returned to the USA early in July 1945.

The Consolidated B-24 Liberator four-engined heavy bombers used for 'Carpetbagger' missions were modified by the removal of the ventral 'ball' turret, the nose guns and any unnecessary equipment, thus lightening the aircraft and giving them more payload volume, speed and range. The rear guns were retained as a limited means of defence against night-fighters. Agents and crated supplies were dropped by parachute through the opening left by removal of the ventral turret. In addition, supplies were loaded into containers designed to fit inside the weapons bay and released from there by the existing equipment.

All flights were made on moonlit nights to facilitate visual navigation by the use of rivers, lakes, railroad tracks and towns as checkpoints. The pilot, co-pilot, and bombardier all had maps to aid them in keeping track of their location, and the navigator kept position by dead reckoning. All the flights were individual, each navigator choosing his route in consultation with the pilot. On flights to French targets the aircraft crossed the coast at some 6,000 ft (1830 m) to avoid light Flak, thereafter dropping to 500 ft (150 m) to avoid night-fighters and to make it possible to verify location at all times by comparing checkpoints on the ground with the plotted course. Limited visibility at higher altitude would have made this process more difficult, if not impossible.

When the aeroplane was only a few miles from the target area, all available eyes began searching for the drop area, which was usually identified by three high-powered flashlights placed in a row, with a fourth at a 90° angle to indicate the direction of the drop. Approaching the target area, the aeroplane decelerated to between 120 and 125 mph (195 and 200 km/h) and dropped to an altitude of 400 to 500 ft (120 to 150 m) at the discretion of the pilot, or at a higher altitude in hilly country. Agents were dropped first, with the supplies following on a second drop.

Pilots often had to fly several miles farther into German-held territory after completing their drops to disguise the actual drop location, thereby making in impossible for any German observer to recognise the aeroplane’s turning point as the drop location. In some cases multiple drops in isolated areas were made at different intervals, and bonfires would be used as drop indicators instead of flashlights. In rare cases air to ground oral radio contact would be made, these being of great importance.