Using the mountain face as a " vertical runway ", members have been able to achieve unpowered horizontal flight at speeds of.
22.
Testing began in July 1960 and by the end of the year the aircraft had achieved both vertical take-off and horizontal flight.
23.
The aircraft's radical design enables it to take off and land vertically and to tilt its rotors forward for fast horizontal flight.
24.
The pilot's seat was mounted on gimbals allowing for movement from 45 degrees in vertical flight to 90 degrees in horizontal flight.
25.
The basic idea in this arrangement was to keep the centerline of the fuselage horizontal in both normal and inverted horizontal flight.
26.
On 19 November 1998, a NASA ER-2 research aircraft set a world record for altitude of in horizontal flight in the weight class.
27.
The Dassault Mirage IIIV achieved transition from vertical to horizontal flight in March 1966, reaching Mach 1.3 in level flight a short time later.
28.
As of 2014, NASA is testing a diesel-electric hybrid 10-foot 10-rotor tiltwing called the GL-10 Greased Lightning, with most propellers folding during horizontal flight.
29.
On 24 March 1966, the first complete flight was made from vertical takeoff transition to horizontal flight deceleration to vertical flight and vertical landing.
30.
Powered types capable of horizontal flight were referred to as dirigible balloons or simply dirigibles ( from the French " dirigible " meaning steerable ).
