Thanks Walt, I did no computer searches on this ahead of time, but will give you the official USN position/nomenclature on the X-?-plane program of Quiz #40. You basically nailed it and more and I appreciate the photo. Well done!
1. X-26A, 1967-to the present-(48 years). It is the longest lived of the X-plane programs.
2. FRIGATE
3. 1967, developed by the U. S. Navy to train test pilot school aviators in yaw/roll coupling. They based the X-26A on the Schweizer SGS 2-32 sailplane.
4. Four X-26As were initially procured (these may have been under a Lockheed contract). Now there are just two X-26As remaining in service at the USNTPS, (U. S. Naval Test Pilot School) at NAS Patuxent River, MD. in support of its curriculum.
Of interest is that the USNTPS uses the U-6A BEAVER, a military version of the deHavillland DHC-2 BEAVER, flown as the tow aircraft for the X-26A FRIGATE. The U-6As began service there in 1968 and now incorporate modern digital avionics systems.
I was TDY once in 1967 to Pax River on the Navy BIS (Board of Inspection and Survey) trials of the Vought A-7B CORSAIR II while working at the Naval Missile Center, Point Mugu, CA. Their task was to wring out the flight qualities of the A-7B, our job was the missile integration aspects. Pax River was unable to do the acoustical testing of both the cockpit environment and the noise at low and high fire rates of the A-7B's rotating 'gatling' gun before releasing the test aircraft to Mugu. So, they requested I perform those tasks while working in the Bioacoustics Branch at Pt. Mugu. One civilian engineer each year at Mugu was chosen to attend the TPS at Pax River. A close friend of mine was chosen and also took the optional flight training offered, stating "It's no fun unless you can do touch and goes in the TA-4". The TPS curriculum is nearly a year in course length, as I recall.