XAT-6E
During 1944, the Army ordered an experimental variant of the AT-6D to test the feasibility of mounting an inline, air-cooled engine in the AT-6 airframe. This experiment
was conducted for two reasons; most Army fighters of the period were powered by inline engines (P-40, P-39 and P-5 I s) and there existed a possibility that there could
be a shortage of Pratt & Whitney Wasp engines since the demand for these engines was exceeding their output. The Army designated this experimental aircraft as the
XAT-6E (the only Texan variant to carry an X designation).
One AT-6D airframe (42-8424 1) was modified with the 575 hp Ranger V-770-9, inverted V, twelve cylinder air-cooled high altitude engine driving a two blade propeller
fitted with a spinner.
Although only half as large in displacement as the Pratt & Whitney radial engine, the improvement in streamlining allowed by the slim lines of the inline engine made the XAT-6E the fastest of the T-6 series. The installation of the inline engine gave the XAT-6E a much longer nose section and led to a compete rebalancing of the aircraft. During flight tests at Eglin Army Air Force Base in Florida, the XAT-6E revealed a top peed of 244 mph and a service ceiling of 30,000 feet, some 6,000 feet higher than any of the radial engine T-6 variants.
The big Ranger engine, however, proved to be mechanically unreliable and a maintenance nightmare. Since the shortage of Wasp engines never materialized, the XAT-6E project never progressed beyond the prototype stage. The prototype XAT-6E survived the war and was later sold as surplus.
The XAT-6E was a standard AT-6D (42-84241), modified to mount a 575 hp Ranger V-770-9 Inline Engine twelve cylinder Inline air-cooled engine. Technical problems with the engine led to the pro- ject being cancelled even though the XAT-6E proved to be the fastest T-6 variant. (AFM)
