In February 1947, the 1st Experimental Guided Missiles Group at Eglin AFB, FL was assigned Service Test No.9-47-2 under the title “Comparative Test of Full Scale Ditching of the B-17”. As its name suggests, the project was instigated to compare semi-scale tests with reality and would allow a degree of confidence in model testing for subsequent aircraft programmes. Additionally it was hoped to gain a better understanding of structural weaknesses in this type of procedure. Initially it was planned to expend up to ten B-17s during the test, which would be remotely-piloted in the same manner as B-24s which took part in similar trials conducted by the NACA.
Completion date for the programme was set for 1 December 1947, with the first aircraft (a drone-configured B-17G) due in April. However those dates soon changed and it was not until 28 May that the first ditching article (B-17G s/n 44-83528, an aircraft which had already taken part as a drone in the Crossroads nuclear test) was delivered. As with all other radio-controlled drones used in the ditching tests, conversion work was done at the Rome Air Depot and also at Columbus, OH. The first machine was ditched successfully on 6 June 1947 and established the procedure whereby test aircraft were recovered from the water for structural investigation. Damage was generally less than expected and radio controlled landings could be made repeatedly in an ideal “3-point” attitude.
In order to conduct the ditching in a suitable environment, the Air Force identified a stretch of Choctawhatchee Bay, 15 miles southeast of Eglin. Here the water to the west of Four Mile Point was shallow and sheltered and also allowed the siting of shore-based instrumentation. A second aircraft (this time designated QB-17G, s/n 44-85504, another Crossroads drone) was successfully ditched there on 22 October. The 1st Experimental Guided Missiles Group was then engaged in two other high-priority programmes for the Air Force (the JB-2 Loon and the Banshee B-29 drone projects) and so further testing was shelved for several months.
Testing recommenced on 11 February 1949 with QB-17G s/n 44-83507 (the third and final Crossroads veteran used during the ditching project), followed by four newly-converted drones comprising 44-83388 (ditched 3 March 1949), 44-83513 (18 March 1949), 44-85648 (1 April 1949) and 44-85546 (24 May 1949). This was the seventh and final aircraft to be ditched.
This is the third ditching aircraft, QB-17G 44-83507:
And the penultimate test machine, 44-85648:
Maybe Mark has some better shots?