Northrop YA-9

The Northrop YA-9 was a prototype attack aircraft developed for the USAF, but passed over in preference for the Fairchild YA-10 that became the A-10 Thunderbolt II in service.
A fly-off of the two prototypes took place between October 10 and December 9, 1972, with the YA-10 declared the winner on January 18 1973. The two YA-9 prototypes were subsequently relegated to NASA for continued flight testing before being quickly retired. One is preserved at the March Field Air Museum at March Air Reserve Base. When retired, the YA-9s' custom-built engines were removed and were later mated to a C-8 Buffalo airframe as part of the NASA-Boeing joint QSRA study into a quiet short-haul commercial aircraft.
My personal opinion is that 'Da hog iz bezt'.