The Dassault Mirage IIIV of France was designed to a NATO requirement calling for a supersonic-capable VTOL (Vertical Take-Off and Landing) fighter aircraft. This Dassault entry became a further development of the already-successful Mirage III fighter series but featured a series of eight small turbofan engines within the fuselage to achieve the vertical lift requirement (a conventional jet engine provided the needed forward thrust for flying). Only two prototypes were built between 1965 and 1966 and the second example was lost to an accident and this essentially ended the entire program. NATO would settle on the Hawker-designed "Kestrel" VTOL prototype in the end - becoming the famous Harrier "jump jet" strike fighter. However, all was not lost from the Mirage IIIV project for some components made their way into the Mirage IIIF and the Mirage F1 fighting platforms.
The Mirage IIIV retained much of the form of the preceding Mirage III seires aircraft and was, itself, developed from the prototype Dassault Balzac V prototype detailed elsewhere on this site. The single pilot sat under a largely unobstructed canopy aft of a nosecone assembly set to house a radar fit. The single turbofan installation, meant to provide the necessary forward thrust, was buried within the fuselage and aspirated by a pair of half-moon intakes located to either side of the cockpit wall. A single jetpipe was used for exhausting the unit. The primary engine was initially the Pratt & Whitney JTF10 turbofan (SNECMA TF104B) but this eventually gave way to the TF106 engine of 16,750lb thrust output.
For vertical lift, a series of eight Rolls-Royce RB162 turbofan lift engines were in play and each of these units provided 4,400lb of thrust. Unlike the Harrier jet, the lift engines of the Mirage IIIV were not positional so as to aid in forward flight - instead they were fixed in place to fire down only.
The wing mainplanes were triangular in their general shape and their surface area was such that no horizontal tailplanes were needed (a Dassault design staple for its fighters). A single vertical tailplane was, however, used and this was seated over the exhaust port of the primary engine installation. A tricycle undercarriage was used for ground-running and was fully-retractable.
While the Mirage III pedigree was a sound one, the challenge lay in the vertical flight quality required of the NATO specs. The series of engines required of the new Dassault aircraft made the Mirage IIIV a complicated and fuel-thirsty development. This challenge, coupled with setbacks typical of such a broad scope design and a lack of private funding made sure that the Mirage IIIV was, more or less, doomed to failure.
A first-flight of one of the two completed prototypes was recorded on February 12th, 1965. The aircraft had an overall length of 59.4 feet, a wingspan of 28.6 feet and a height of 18 feet. While early testing yielded speeds nearing Mach 1.32, the aircraft's maximum speed was listed at Mach 2.04.
It was a large and fast aircraft with plenty of potential by 1960s standards and would have held a career spanning three decades or more had it succeeded in testing. However, it was a technological nightmare with limited range and ballooning weight - qualities that kill most military fighter programs.
The second prototype followed into the air in June of 1966 and this model carried the TF306 turbofan engine of 18,500lb thrust output. That November, this example was lost in an accident and the Mirage IIIV program never recovered. Meanwhile the British Harrier went on to have a very successful combat career.