In early 1960, major aviation manufacturers in France were asked to submit proposals for SHAPE’s GOR 2. This stipulated a VTOL aircraft with separate engines for lift and for horizontal flight.
Two projects by Dassault and Sud Aviation were submitted, and it was the Dassault entry, the Mirage IIIV which was chosen for prototype production. This employed eight RB.162 engines for lift and one TF-10 for wingborne flight.
In July 1960, at the request of the French Defense Minister, Dassault and Sud-Aviation decided to jointly undertake the project in two phases.
Phase 1 would prove the feasibility of the configuration by a subsonic prototype designated the Dassault-Sud Balzac V-001. Besides its role as a prototype of the VTOL Mirage-III, the Balzac V-001 would be used for the familiarization of test pilots with VTOL flight, the study of the problems of vertical flight and to develop the control system intended for the Mirage IIIV VTOL fighter.
Phase 2 would cover the construction of the Mach 2 capable Mirage IIIV, which would be equipped with more powerful lift and propulsion powerplants than the Balzac, would carry two internal 30-mm cannons and would be capable of VSTOL operation, nuclear and conventional strike. Dassault retained overall responsibility for both phases.
In 1961, in Phase two of the competition, the NATO requirement evolved towards a supersonic vertical take-off aircraft and resulted in the initial choice of the British Hawker P.1154 and the French Mirage IIIV. But the competition was canceled. Nonetheless, the French government ordered the Balzac V-001 prototype. The contract was awarded on 1 September 1961.
Balzac Construction, Systems and Equipment
The Balzac V was not an entirely new aircraft. The aircraft had started its flying career in the late 1950’s, as the Mirage III 001, the first prototype of the highly successful Mirage III family. The Balzac V used the airframe of the Mirage III 001 interceptor, equipped with one Bristol Orpheus 3 engine of 2,200 kg thrust for wingborne flight and eight Rolls Royce RB.108 engines of 1,000 kg thrust each, for vertical flight.
Mounting the vertical lift engines in the airframe was the first problem the project faced, and this was solved by Rolls Royce engineers. The lift engines were mounted two by two in four compartments of the aircraft on either side of the air duct of the Orpheus 3 engine, and were supplied with air via four intakes situated above the fuselage. Their exhaust pipes were situated in apertures with blanking caps, which would be closed during normal rapid flight. The half-cone intakes of the propulsion engine were on each side of the cockpit.
The Balzac V was designed by the team of Yves Thiriet, assisted by Jacques Albetto. It used hydraulic-powered aerodynamic control surfaces (elevons and rudder) for conventional flight. For control in the vertical mode, when the speed would be less than the normal minimum flight speed, it used air jets (puffers) located under the nose, tail and wings. The air, drawn from special lift motors, was distributed by a control valve which the pilot could manipulate using the joystick, as on a conventional aircraft.
The unique Balzac prototype, like the early Mirage family, incorporated a 60° delta wing with a streamlined fuselage ending with a needle nose and a stepped canopy. The fuselage was of monocoque construction, and was wider than the standard Mirage-III fuselage because it housed the propulsion engine as well as the lift engines, installed in four pairs on either side of the air duct leading the propulsion engine at the rear. The two air inlets for this engine were mounted on either side of the fuselage, near the cockpit.
Ducts and compressed air ejection nozzles were on the wing’s leading edge.
The 1,650 liter JPT fuel load was contained in two symmetrical groups of tanks on either side of the aircraft. Each group consisted of one 215 liter recuperator tank installed at the center of gravity, with one wing tank and one forward fuselage tank. In all, 890 liters were contained in the fuselage and 760 in the wing.
The pilot was provided with a Martin Baker ejection seat. There was no pressurization and no air conditioning but there was a small oxygen supply.
The equipment included two light UHF radio sets, a light runway telephone (for the first flights) and teledata instrumentation recording.
As rolled out, the Balzac was equipped with a fixed landing gear, designed to gather information on take-off and landing loads.
Development and operations
Dassault Chief Test Pilot René Bigand was assigned to carry out the initial flight testing on the Balzac. A veteran of the French Indochina war, Bigand had flown daring close support missions behind enemy lines before joining the CEV, where he took part in flight tests of the Trident mixed power interceptor prototype beginning in late 1955. He made the first flight of the advanced Etendard IV-MD fighter bomber version on 20 June 1959, and tested other Etendard and Vautour fighters. During one flight, a Vautour prototype went into a spin and Bigand bailed out safely.
After the CEV and a senior administrative position at the French Air Force HQ, Bigand joined Dassault in the late 1950s, and made the first flight and the first double-sonic flight of the Mirage IV strategic bomber before his assignment to the Balzac V program.
In preparation for his VTOL flights, Bigand was sent to England, where he flew the SC.1 VTOL research aircraft.
Bigand made the first static lift engine test under a gantry on 1 June 1962. Ground runs of the Balzac took place on 31 July 1962 and the first tethered hover on 12 October 1962 at Melun-Villaroche, the aircraft being attached by nylon cables fixed to the front lifting point and the main landing gear. A second tethered flight was made on the same day, and a third on 15 October. Testing of the control system in hovering flight was completed during these three captive sorties.
Bigand made a low-level first free hover on 18 October, and on 25 October, during its third free flight, the aircraft remained in hover for more than two minutes. On 6 November, the Balzac was demonstrated to the press on its ninth free flight.
The initial sorties of the Balzac were carried out with a fixed landing gear. During the very harsh winter of 1962 and early 1963, the aircraft was grounded at Dassault’s St. Cloud facilities for the installation of a retractable Messier landing gear, a ventral fin and a brake parachute, in preparation for its forthcoming conventional flights. Corrective action was also done on the puffers.
Bigand made a short hop along the runway at Melun-Villaroche on 1 March 1963, and the Balzac’s first conventional flight on the following day. It was the Balzac’s tenth sortie. Six conventional flights followed in a quick succession then, on 18 March, the Balzac achieved its first transition from vertical to horizontal flight, during Flight 17. A decelerating transition from wingborne flight to VTOL landing was performed successfully on 28 March, during Flight 18. A milestone in the program was the Balzac’s first full transition on 29 March 1963, during Flight 19. This completed the essential part of the flying trials program. The aircraft was accepted by the CEV on 12 April 1963. Flight 33 took place on 24 April, and Flight 88 was logged on 28 July.
Dassault test pilots Bigand and Jean-Marie Saget performed all the contractor flying, which was concluded after a successful public demonstration at the Paris Air Show of 1963.
The aircraft logged its Flight 97 in 1963, with the two Dassault pilots and CEV pilot Jacques Pinier taking turns in the cockpit.
Pinier was making the CEV’s fifth Balzac flight, Flight 112, on 27 January 1964, when he lost control, with the aircraft crabbing at a speed and angle of attack which were later identified as critical. The Balzac crashed, and Pinier was fatally injured.
A veteran of 200 combat missions in Indochina, the 37-year old Pinier had been a test pilot with the CEV since 1953 and had flown most of the French experimental aircraft of the 1950’s. He was famous for his record altitude flights of 1958 on the rocket/jet Trident interceptor prototype, and flew the Mirage-III prototypes at Istres and Mérignac, before being assigned to the ill-fated Balzac V.
Despite the accident, the aircraft was repairable, and plans were drawn for further testing with the introduction of new pilots. The aircraft was rebuilt and resumed flight testing at Melun-Villaroche on 2 February 1965 with René Bigand at the controls. It was used essentially to work out piloting techniques and aerodynamic devices to improve transversal handling. It took part in the Paris Air Show in June that year, and had logged a total of 73 hrs and 40 min of flight time by 8 August.
On 8 September 1965, during Flight 179, the Balzac crashed again. USAF test pilot Major Philip Neale, who was flying the aircraft on exchange duty from Edwards AFB AFFTC ejected, but his parachute did not open and he was killed. The aircraft was completely destroyed.
A 1959 graduate of the USAF Test Pilot School, Major Neale had flown US VSTOL research aircraft and was flying the Balzac as part of a joint US/French VTOL information exchange program.
Balzac pilot René Bigand would die on 18 May 1967, in the crash of the Mirage F.1 prototype near Istres.
Despite its tragic crashes, the Balzac allowed the Mirage IIIV program to proceed. Two Mirage IIIV prototypes were flown. The first accomplished 41 flights then was withdrawn. The second crashed on its Flight 24 but the pilot Michel Jarriges ejected safely. Dassault dropped its VTOL work, shifting to variable geometry.
RAE test pilot Clive Rustin had been named to fly the Balzac and the second Mirage IIIV shortly before they crashed.
The text above is excerpted and translated from HPM Publications’ first book in French:
Dassault-Sud Balzac V 001 L’Histoire Complete