Aerospatiale X 910 tilt rotor

[MIRAGE 4000]

Aerospatiale study in the 70' a tilt rotor program, the X 910. It was only a "paper plane", but the rotor was tested.

 

[Hood]

A few figures for this interesting design. The X 910 dates from 1974, it was designed to carry a pilot and six passengers. Powered by two 1650shp Arriel I turboshafts it was to have a top speed of 321mph and a range of around 500 miles. Span was 7m, length 8.7m and height 3.3m.

 

[Jemiba]

See here, too :http://www.vstol.org/FrenchVSTOLRotorcraft.pdf

 

[Iranian F-14A]

Looks as if they used at least the cabin of the SA-365 Dolphin as a starting point.

 

[MIRAGE 4000]

I have this little drawing from Aerospatiale
(Well, I find a good photo on the Rotojet project). Will post it !

 

[amsci99]

Very interesting project, any mention of this in French aviation magazines such has 'Le Fana de L'Aviation'?

 

[Dronte]

Another view of the model

 

[Triton]

Via Internet Archive:

The X 910, was similar to the contemporary American Bell XV-15. The first wind tunnel tests were conducted at Marignagne in 1974 with a 1/5-scale model. Test were conducted with a full-scale tilt-rotor system at the Office National d'Etudes et de Recherches Aérospatiales (ONERA) S1 subsonic wind tunnel in Modane-Avrieux during June/July 1975 and June/July 1976. The conversion between hover and forward flight was the primary focus of the tests. In April 1977, the first flight was envisioned for 1981, but the program was soon cancelled.

• Power: Two Turboméca Arriel I turboshaft engines with 650 hp (485 kW) internal in the fuselage and drove the rotors via shafts
• Rotor: 5 m (16.4 ft) diameter; were able to operate in the horizontal position while the aircraft was on the ground, something that cannot be done with the XV-15 and V-22 Osprey.
• Maximum Speed: 517 km/hr (279 kt)
• Range with 4 passengers: 800 km (432 kt)
• Range with 6 passengers: 450 km (243 kt)
• Wing span: 7 m
• Length: 8.7 m
• Height: ~ 3.3 m
• Airfoil: NACA 63A221
• Maximum VTO Weight: 1,640 kg (3,615 lb)
• Operational gross weight: 2,560 kg (5,645 lb)
• Prototype gross weight: 2,455 kg (5,412 lb)
• Capacity:

Source:
http://web.archive.org/web/20070306200806/http://www.aiaa.org/tc/vstol/unbuilt/index.htm

 

[Triton]

Rename topic to " Aerospatiale X 910 tilt rotor"?

 

[Antonio]

Renamed

 

[Jemiba]

In InterAvia (sorry, didn't wrote down, in which issue ) I once found a drawing of the X-910,
which seems to depict it with a fixed landing gear. Another interesting point, I think, are
the slats, shown deployed in this drawing.

 

[toura]

Hi Jens
Yes. It seems that it is a fixed landing gear

 

[fightingirish]

See here, too :http://www.vstol.org/FrenchVSTOLRotorcraft.pdf

Another link:

International V/STOL Historical Society (IVHS) - www.vstol.org- French Low-Speed V/STOL Concepts of the Twentieth Century - AHS Forum 58 STOVL/Powered Lift Session 11 June 2002
Found at Popular Rotorcraft Association (PDF)

 

[hesham]

Hi,


the Aerospatiale X.910.



L’histoire des hélicoptères
en France
depuis 1945

 

[VictorXL188]

Further to the previous posts, here's the entry regarding the Aerospatiale X-910 from the Air Data section of the June 1977 issue of Air International

 

[hesham]

Nice find Victor.

 

[hesham]

From L+K 12/1977.

 

[hesham]

From Icare 1973.

 

[VTOLicious]

From Icare 1973.

Air Taxi ideas 46 years ago

 

[hesham]

In InterAvia (sorry, didn't wrote down, in which issue ) I once found a drawing of the X-910,
which seems to depict it with a fixed landing gear. Another interesting point, I think, are
the slats, shown deployed in this drawing.

From Aviation magazine 1975.

 

[hesham]

From Technika Lotnicza 1978

 

[Scott Kenny]

Via Internet Archive:

The X 910, was similar to the contemporary American Bell XV-15. The first wind tunnel tests were conducted at Marignagne in 1974 with a 1/5-scale model. Test were conducted with a full-scale tilt-rotor system at the Office National d'Etudes et de Recherches Aérospatiales (ONERA) S1 subsonic wind tunnel in Modane-Avrieux during June/July 1975 and June/July 1976. The conversion between hover and forward flight was the primary focus of the tests. In April 1977, the first flight was envisioned for 1981, but the program was soon cancelled.

• Power: Two Turboméca Arriel I turboshaft engines with 650 hp (485 kW) internal in the fuselage and drove the rotors via shafts
• Rotor: 5 m (16.4 ft) diameter; were able to operate in the horizontal position while the aircraft was on the ground, something that cannot be done with the XV-15 and V-22 Osprey.
• [...]

Source:
http://web.archive.org/web/20070306200806/http://www.aiaa.org/tc/vstol/unbuilt/index.htm

That's an interesting design choice. Leaves about a half meter clearance between proprotor tip and the ground, which is a little less than I like. Also means fairly small rotors relative to XV-15 (7.6m rotors but also a 2x1500hp), which means increased downwash force.

 

[yasotay]

Is there somewhere that explains the rational for stopping the program? XV-15 was demonstrating that tilt rotor was technologically viable. I have always assumed that it was a fiscal decision that there was not enough profitability for the investment.

 

[Scott Kenny]

Is there somewhere that explains the rational for stopping the program? XV-15 was demonstrating that tilt rotor was technologically viable. I have always assumed that it was a fiscal decision that there was not enough profitability for the investment.

I mean, it was an X-program. All it was supposed to do was demonstrate technological viability.

One of the killers for the first Sikorsky ABC compound helo (XH-59?) was that when the two projects were getting demonstrated somewhere, the XV-15 team would just fly there while the Sikorsky team would load their stuff onto a train.

But IIRC a major issue with the AW609 has been the regulators constantly adding yet another hoop to jump through every time the Tilt-rotors were ready to certify.

 

[hesham]

From Technika Lotnicza 1982