In 1977, General Dynamics produced the “Sneaky Pete” design for a stealthy fighter or attack aircraft. The design was quite similar to that of the later McDonnell-Douglas A-12 Avenger II, a delta flying wing with underslung inlets and a straight trailing edge. There were notable differences: an additional inlet on the upper surface, the exhaust was on the upper surface and there was a single pilot. It also appears that the Sneaky Pete had vertical stabilizers on the upper surface that would fold flush during cruise. Performance, weights, dimensions are all sadly unavailable. Sneaky Pete was part of the design evolution leading to the ATF (eventually won by Lockheed and became the F-22), though it seems very unlikely that it would have been capable of supersonic flight, much less supercruise.
Dec 242012