Dassault Balzac V

The Dassault Balzac V was a vertical take-off and landing (VTOL) testbed. It was built by Dassault Aviation from a prototype Mirage III to test the configuration for the Mirage IIIV. The Balzac V began tethered hovering on October 13, 1962 and achieved the first free hover only six days later, two months ahead of schedule. The first accelerating transition from vertical take-off to horizontal flight took place on its seventeenth sortie on March 18, 1963.

The aircraft crashed on January 10, 1964, on its 125th sortie, during a low-altitude hover. During a vertical descent the aircraft experienced uncontrollable divergent wing oscillations, the port wing eventually striking the ground at an acute angle with the aircraft rolling over because of the continued lift engine thrust. The loss was attributed to loss of control because the stabilising limits of the three-axis autostabilisation system’s ‘puffer pipes’ were exceeded in roll. Although airframe damage was relatively light, the Centre D’Essai en Vol test pilot, Jacques Pinier, did not eject and died in the crash.

The aircraft was rebuilt, and resumed flight testing on February 2, 1965. On September 8, 1965, the aircraft suffered another fatal crash, once again while in a low altitude hover. The aircraft was being evaluated by United States Air Force Major P E Neale, as part of a Franco-American information exchange on VTOL programmes. Major Neale made an unsuccessful ejection outside the ejection seat’s escape envelope. The findings of the accident investigation were never made public. It was speculated that hydraulic control difficulties coupled with excessive use of the lift engines resulted in fuel starvation and the flame-out of all nine engines. Once again, the damage was not irreparable, but this time the aircraft was not rebuilt, as flight development of the Mirage IIIV prototype was already underway.