It was on this day in aviation history that the Scaled Composites Model 281 Proteus made its first flight. The tandem wing high altitude research aircraft was designed by Burt Rutan, only one was built.
The aircraft was designed to investigate the use of high altitude aircraft as telecommunication relays. The aircraft has a service ceiling of 61.000 feet (19.000 meters) and has an endurance of more than 14 hours (apparently up to 18 hours!)
The aircraft is made of composites with a "Graphite-Epoxy" sandwich construction. It has an adjustable wingspan, depending on mission requirements. The basic 77' 7" (23.65 meters) can be enlarged to 92'(28 meters) by installing removable wingtips. Besides its unique appearance, the aircraft has another unique capability. Normally the aircraft is flown by two pilots in the pressurised hull, it can also be flown with the crew "monitoring" the flight or it can be flown under full control from the ground.
The aircraft is equipped with a state of the art Autopilot with, amongst others, a station-keeping function. It also features a SATCOM bi-directional communication system which is used for aircraft performance and payload data transmission. After the first flight, flight testing continued out of Mojave Airport till the end of 1999. That same year, in June, the aircraft made its public debut at the Paris Airshow after a non-stop flight for Bangor, Maine (USA) to Paris Le Bourget Airport in France. a distance of 3300 nm. The aircraft holds several FAI (Fédération Aéronautique Internationale) records
Altitude record for its category of aircraft, 63.245 feet (19.277 meters)
Altitude in horizontal flight, 62.385 feet (19.015 meters)
Altitude with 2200 lbs (1000 kg) payload, 55.994 feet (17.067 meters)
Its wing design was used (although slightly changed) for the Rutan Model 318 White Knight carrier aircraft and the DARPA X-37, The aircraft was used for testing a large number of research projects, due to its unique configuration which allowed it to carry large test pods under its fuselage, from camera systems to the radar system for the Global Hawk. Some specifications for the Proteus
Crew: Two (pilot and co-pilot) or 0 when
Length: 56 ft 4 in (17.17 m)
Wingspan: 77 ft 7 in (23.65 m)
Height: 17 ft 8 in (5.38 m)
Wing area: 300.5 sq ft (27.92 m2)
Empty weight: 5,860 lb (2,658 kg)
Max takeoff weight: 12,500 lb (5,670 kg)
Powerplant: 2 × Williams FJ44-2 turbofans, 2,293 lbf (10.20 kN) thrust each
Maximum speed: 313 mph (504 km/h, 272 kn)
Cruise speed: 219 mph (352 km/h, 190 kn) at 20000 ft
Endurance: 14 hours at 1,150 miles (1,850 km) from base
Service ceiling: 61,000 ft (19,000 m) mid-mission altitude
Rate of climb: 3,400 ft/min (17 m/s)