Schweizer X-26A
Lockheed X-26B

First Flights: X-26a - July 3, 1962: X-26b - ?? July, 1967                
Mission: 
Very early "stealth-type" observation platform
Major Accomplishments:
Possibly the most secretive of the X-Planes, little is known of its history or accomplishments.
Power Source: Continental O-200-A four cylinder piston engine (horizontally opposed pistons, similar to BMW or Subaru configuration). 100hp.

   X-26a  X-26b
Wing Span:  57' 1"  57' 1"
Length:  26' 8"  30' 11"
Weight (Loaded):  1430 lb  2182 lb
Maximum Speed:  158 mph  115 mph
Maximum Altitude:  18,500'  13,000'

Additional Information: A total of X-26's were built, 4 as X-26a and 2 as X-26b. These planes were flow in Vietnam during the United States military action there, and designated as SGS 2-32 (X-26a) and QT-2 (later  QT-2PC). 

3 of the X-26a's were destroyed in accidents, the remaining X-26a is housed at the Army Aviation Museum, Fort Rucker, Alabama. Apparently no intact X-26b's survive.