Aircraft History

Although somewhat forgotten among the ranks of war bird enthusiasts today, the Vultee BT-13, played a vital role in training many USAAC and USAAF pilots. This is manifested in a total production run of 11,537 aircraft in five variants. (Let me just insert something here... Now, the 11,537 is actually unverified. I am conducting research on all serial numbers from the Air Force in Georgia and other resources.  As of today I have three conflicting numbers.  11,537 +1 prototype serial # 200 which was converted later in 1943 to a BT-13A.  However, other resources claim, 13,740 or 13,100 or 10,375.  I am trying to dig and find out total production.) In fact the BT-13 production run outnumbers all other Basic Trainer (BT) types produced. It was back in 1938 that Vultee Aircraft's chief designer, Richard Palmer, began the design of a fighter. At this time the USAAC issued a requirement and design contest for an advanced trainer for which substantial orders had been promised to the victor. Palmer began to adapt his design concept from a fighter to that of an advanced trainer and the result of this was the V-51 prototype. The aircraft made its maiden flight sometime during March of 1939 as a cantilever low-wing monoplane of all-metal construction. Despite the use of metal throughout the design the control surfaces remained fabric-covered. The prototype was powered by a Pratt & Whitney R-1340-S3H1-G Wasp radial rated at 600 hp (447 kW) driving a two-blade variable pitch metal propeller. Other features included an enclosed cockpit for the crew of two, integral fuel tanks in the wings, and a hydraulic system for the operation of the flaps and retractable main landing gear. The V-51 was entered into the USAAC competition as the BC-51 during May 1939. The USAAC instead chose the North American BC-2, but purchased the BC-51 prototype anyway. Despite the disappointment, Palmer was not finished yet. He continued to refine the design of the VF-51 into the VF-54 in an attempt to meet the expectation of an export market for just such a trainer. The VF-54 used the same basic airframe as the VF-51,but was fitted with a lower powered engine. No export sales were made. From this design, evolved the VF-54A. Instead of retractable gear, it had fixed gear very nicely faired and a revised power plant of a Pratt & Whitney R-985-T3B Wasp Jr. radial rated at 450 hp (335.5 kW) and the Vultee BT-13 Valiant was born. The USAAC was made aware of the improvements made to the aircraft and in August 1939 the type was ordered as the BT-13. The initial order was for 300 aircraft with a Pratt & Whitney R-985-25 radial and the first of these was accepted by the USAAC in June of 1940. The BT-13A was produced to the extent of 7,037 aircraft and differed only in the use of a P&W R-985-AN-1 radial engine and lack of landing gear fairings. There were 1,125 BT-13B's produced and differed from the A model in having a 24-volt, rather than the original 12-volt electrical system. The next variant was actually designated BT-15 due to the fact that Pratt & Whitney found it impossible to keep up production of the R-985 engine. Instead a Wright R-975-11 radial was substituted into the 1,263 aircraft produced. The US Navy began to show an interest in the aircraft as well and ordered 1,150 BT-13A models as the SNV-1. In addition, the Navy ordered some 650 aircraft designated as SNV-2 roughly equivalent to the BT-13B. Once in service, the aircraft quickly got it's nickname of "Vibrator" due to the fact that it had a tendency to shake quite violently as it approached it's stall speed. The BT-13 served it's intended purpose well. It and its successors were unforgiving aircraft to fly, but were also extremely agile. Thus the BT-13 made a good aircraft to help transition many hundreds of pilots toward their advance trainers and fighters yet to to be mastered. 1932: When Lockheed-Detroit fails, Gerard "Jerry" Vultee forms the Airplane Development Corp. financed by E.L. Cord. 1934: Reformed as the Airplane Manufacturing Corp. owned by AVCO (of which Cord is a partner). 1936: Renamed the Vultee Aircraft Division of the Airplane Manufacturing Corp. 1940: AVCO merges Stinson with Vultee to form Vultee Aircraft Inc. 1943: Vultee acquires Consolidated to form Consolidated-Vultee (Convair).