Flying Forever - Long Range Flyers

Major Carl Spaatz and Capt. Ira Eaker, of the US Army Air Corps, discussed in late 1928 the possibility of conducting an endurance flight using a C-2A trimotor (a US-built Fokker F-VIIA/3m) refuelled in flight by a Douglas C-1. Approval was obtained for trials, with a C-2A and two C-1s being provided. The C-2A, named "Question Mark", took off on January 1st, 1929, with a crew of five under command of Spaatz.

Over the next week, a C-1 hung twenty feet above the trimotor on forty-three occasions. Thirty-four of these were to transfer fuel, and the rest were for general provisions. Over five thousand gallons of fuel in all were transferred via a lowered line caught by a crew member of "Question Mark" and guided into a fuselage tank.

Repairs were made in flight by Sgt. Hooe, who climbed out onto a specially built catwalk around the engines. Only when one of the Wright Whirlwind engines stopped with plugged grease outlets did "Question Mark" land at Metropolitan Airport, Los Angeles, after 150 hrs. and 40 min. in the air.

The flight of "Question Mark" sparked controversy in the aviation press, factions of which treated it as a failed stunt. Nonetheless, over forty refuelled endurance flights were attempted that same year, many attracted by visions of sponsorship and financial rewards. By the end of 1929, the record stood at 420 hours, and in June 1935 it was reset at 653 hours. Some contenders, often flying solo, tried picking up fuel from pacing cars.

In Britain, apart from the RAE trials, a number of private and commercial projects continued. In 1932 the Hon. Mrs. Victor Bruce carried out trials with a Saro Windhover flying boat, refuelled by Bristol Fighters. Her attempt that August to set a women's refuelled endurance record ended unfortunately when her aircraft suffered lubrication problems.

A veteran of long-distance flights in the 1920s, Sir Alan Cobham developed a deep interest in airborne refuelling, in 1931 considering it a means of flying non-stop from England to Australia. Such long flights could, he believed, be conducted in far shorter times without the need to land at prepared fuel points. He tested his theories with aircraft trailing ropes, and in 1932 obtained an Airspeed Courier, in the confidence that he could proceed with the idea and achieve some success.

He received official support and encouragement, agreeing to set a target in India as a less ambitious first experiment, with Royal Air Force aircraft being adapted as tankers. Cobham, with Sqn. Ldr. W. Helmore of RAE as his refuelling operator, set off for Karachi on 22 September 1934. The attempt failed badly. The first tanker, a Handley Page W10, crashed after refuelling was achieved. The second, a Courier, was obliged to land at Malta with a disconnected throttle linkage.

Not discouraged, Cobham sold his aviation display business to C.W.A. Scott (later, a competitor in the 1934 England to Australia air race, flying one of the DH.88 Comets). Cobham set up Flight Refuelling Limited. In 1935 he managed to obtain a loan of two Vickers Virginias from the Air Ministry for trials, and held discussions with Imperial Airways about refuelling on trans-Atlantic routes.

Imperial were briefly interested, but in 1937 divested themselves of their interest in Flight Refuelling Limited. Development continued, and after tests at Farnborough in August 1937, Flight Refuelling Ltd. was awarded an Air Ministry contract and took over development from the RAE, using a variety of aircraft.

Refuelling trials with the Short Empire flying boat began early in 1938, using G-ADUV Cambria and an Armstrong Whitworth AW23 as tanker, with a view to opening a trans-Atlantic service flown by the S.30 Empire flying boat. A parallel scheme had already been initiated, the parasite combination of an Empire boat launching a mail floatplane from its back, and this continued alongside the refuelled passenger flying boats.

The trans-Atlantic service began on 5th August, 1939, with a Short S.30 G-AFCU flown by Godfrey Cabot taking off from Southampton to be refuelled over Ireland by Harrow G-AFRL and Newfoundland by G-ARFG or G-AFRH. Later, Cabot was joined by a S.30 G-AFCV Caribou. The war truncated this service, the last flight taking place on 29 September 1939.

The two flying boats were taken into RAF service and were destroyed in Norway the following May. The UK based Harrow was destroyed in an air raid in June 1940, and those in Newfoundland were put aside for later refuelling needs. They were never again used in that role and were assigned other duties, then transferred to the Royal Canadian Air Force.

With the outbreak of war, the Air Ministry remained interested in aerial refuelling for military purposes, and Flight Refuelling Limited continued its work into World War 2.