The SNECMA Atar Volant or C.400 P1 was a French

turbojet The turbojet is an airbreathing jet engine which is typically used in aircraft. It consists of a gas turbine with a propelling nozzle. The gas turbine has an air inlet which includes inlet guide vanes, a compressor, a combustion chamber, and ...

engine An engine or motor is a machine designed to convert one or more forms of energy into mechanical energy. Available energy sources include potential energy (e.g. energy of the Earth's gravitational field as exploited in hydroelectric power ge ...

produced by

SNECMA Safran Aircraft Engines, previously Snecma (''Société nationale d'études et de construction de moteurs d'aviation'') or Snecma Moteurs, is a French aerospace engine manufacturer headquartered in Courcouronnes and a subsidiary of Safran. It d ...

as part of their "

Atar Atar, Ahtra, Atash, Azar () or ''Dāštāɣni'',, s.v. ''agni-.'' is the Zoroastrian concept of holy fire, sometimes described in abstract terms as "burning and unburning fire" or "visible and invisible fire" (Mirza, 1987:389). It is conside ...

" series. Encased in a basic fairing which could hold

fuel A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work (physics), work. The concept was originally applied solely to those materials capable of releasing chem ...

and remote-control equipment, the unit weighed , and generated a

thrust Thrust is a reaction force described quantitatively by Newton's third law. When a system expels or accelerates mass in one direction, the accelerated mass will cause a force of equal magnitude but opposite direction to be applied to that ...

of approximately 6,200 pounds-force (27.6 kN); the Atar Volant was able to cause vertical lift, which was precisely its purpose. There were later Atar Volant models, each made improvements and alterations to the previous designs, and eventually resulted in a full-fledged craft.

Background and purpose

The Coléoptère was a

VTOL A vertical take-off and landing (VTOL) aircraft is one that can takeoff and landing, take off and land vertically without relying on a runway. This classification can include a variety of types of aircraft including helicopters as well as thrust- ...

or "Vertical Take-Off and Landing" aircraft that was designed by SNECMA during the 1950s. While the Coléoptère was not the first VTOL aircraft, none of its predecessors had an

annular Annulus (or anulus) or annular indicates a ring- or donut-shaped area or structure. It may refer to: Human anatomy * ''Anulus fibrosus disci intervertebralis'', spinal structure * Annulus of Zinn, a.k.a. annular tendon or ''anulus tendineus com ...

wing A wing is a type of fin that produces both Lift (force), lift and drag while moving through air. Wings are defined by two shape characteristics, an airfoil section and a planform (aeronautics), planform. Wing efficiency is expressed as lift-to-d ...

designed to land vertically. The benefit of this annular wing was the requirement for very little landing or take-off space. However, the design of the Coléoptère met with many problems, such as overcoming the

torque In physics and mechanics, torque is the rotational analogue of linear force. It is also referred to as the moment of force (also abbreviated to moment). The symbol for torque is typically \boldsymbol\tau, the lowercase Greek letter ''tau''. Wh ...

imparted to a vertical engine by its own

turbine A turbine ( or ) (from the Greek , ''tyrbē'', or Latin ''turbo'', meaning vortex) is a rotary mechanical device that extracts energy from a fluid flow and converts it into useful work. The work produced can be used for generating electrical ...

wheels and rotating

compressor A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor. Many compressors can be staged, that is, the gas is compressed several times in steps o ...

, and discovering and developing a method of balancing the craft on the column of air released from its jet pipe during the take-off and landing phase, as well as, more particularly, during manoeuvres out of the vertical positioning. To address some of these problems, as well as to provide a way to achieve vertical lift, SNECMA set to work on what was to become the first model of the Atar Volants.

Improvements, alterations and later models

There were at least four Atar Volant models constructed, each improving or making alterations on the last: the first (C.400 P.1), C.400 P.2, C.400 P.3. and the last, the C.450-01. The second in the series had much success at an international air display in

Le Bourget Le Bourget () is a commune in the northeastern suburbs of Paris, France. It is located from the center of Paris. The commune features Le Bourget Airport, which in turn hosts the Musée de l'Air et de l'Espace (Air and Space Museum). A very ...

, in

Paris Paris () is the Capital city, capital and List of communes in France with over 20,000 inhabitants, largest city of France. With an estimated population of 2,048,472 residents in January 2025 in an area of more than , Paris is the List of ci ...

, and the third became a full-scale coleopter in its own right, due to numerous improvements and alterations made to the model. The C.450-01 model's maiden flight took place in May 1959. Two months later, while being put through its paces, the single

prototype A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics, design, electronics, and Software prototyping, software programming. A prototype ...

crashed. The

pilot An aircraft pilot or aviator is a person who controls the flight of an aircraft by operating its Aircraft flight control system, directional flight controls. Some other aircrew, aircrew members, such as navigators or flight engineers, are al ...

was seriously injured, and the prototype wrecked, resulting in the abandoning of its development and the project.

Variants

''Data from:'' Jane's All the World's Aircraft 1958-59 ;C.400 P.1: First remotely piloted research vehicle powered by a Atar 101DV mounted vertically. ;C.400 P.2: The second research vehicle with an ejection seat for the pilot, sat on top of the fuselage. First free flight on 14 May 1957 ;C.400 P.3: The third research vehicle with a tilting ejection seat in an enclosed cockpit, similar to that of the SNECMA C.450 Coléoptère.

Specifications (C.400 P.2)

References

Bibliography

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External links

Virtual Aviation Museum

* ttp://modelbox.free.fr/photoscopes/Coleo_Phot/index.html French information source
Above Source Translated into English
{{Snecma aeroengines 1950s turbojet engines Atar Volant Atar Volant Tailsitter aircraft 1950s French experimental aircraft