The plane, with three pilots and a number of other cabin crew, then turned round and headed back to Heathrow, flying at subsonic speed and landing safely at 2.06 pm.
The aircraft's fixed-wing profile with large wing leading edge root extensions gives good manoeuvrability and control at subsonic speed including manoeuvres at high angles of attack.
To improve the aircraft's longitudinal stability, and to avert stall at steep angles and subsonic speed, there are two shallow upper-surface fences on each wing.
Once the vehicle returns to the lower atmosphere and drops to subsonic speeds, the jet engines will reignite for a powered landing back at the spaceport.
The variable sweep wings are set at 20° for take-off, loitering and landing, and automatically change to a maximum sweep of 68°, which reduces drag for high subsonic to supersonic speeds.
There was a storm in the circle; the lightning strokes of claws slashed out and the thunder of snarls reverberated almost subsonically amongst the quiescent ruins.
The slow, gentle flicker of candles at dinner and the explosions inside the pulse jet share one characteristic: They burn subsonically , in a process scientists call deflagration.
The aircraft departed from Paris at around 11: 30 and flew out over the Atlantic Ocean for a final supersonic sprint, before heading overland subsonically to the former Aerospatiale factory at Toulouse, where a ceremony was planned to greet the aircraft.
It loiters subsonically at very high altitudes over the region of interest for extended periods of time without refueling.
Similarly, the jet moving overhead subsonically pushes air out of the way and, in so doing, generates pressure waves that move at the speed of sound.