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.
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.
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.