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The Proteus is a unique aircraft originally conceived as a high-altitude, long-duration telecommunications relay platform for use over major cities.  It was designed and built by Scaled Composites and first flight was flown from Scaled's flight test and development facility in Mojave, California on 26 July, 1998. Since its maiden flight, it has demonstrated its ability to support a multitude of missions and has been deployed worldwide.

Aircraft Description

The aircraft features an unconventional tandem-wing, twin-boom configuration with two centrally mounted turbofan engines. This configuration allows for Proteus (so named for the mythological Greek sea-god who could change his appearance at will) to be reconfigured for a variety of other missions, such as atmospheric research, reconnaissance/surveillance, and commercial imaging.  The basic systems of the aircraft are derived from common general aviation components.  This enabled the aircraft to demonstrate exceptional reliability and low operating costs when compared to other purpose built experimental aircraft.  It also allows deployment to general aviation airports by a ground crew of two with minimal support equipment.

The aircraft employs modular construction that enables payloads to be carried in a variety of locations.  The main landing gear is widely set, allowing for large externally-mounted payloads to be carried beneath the fuselage.  Payloads are commonly carried in pods attached near the center of gravity of the aircraft.  This location allows the weight of the payloads to vary widely without an appreciable effect on the aircraft stability.  In addition to the central mount, light payloads can be attached to extensions of the tail booms, as well as hard points beneath the wings.

The aircraft was designed to cruise at altitudes from 50,000 to more than 63,000 feet and remain on station for more than 12 hours. While carrying a standard 2200lbs payload, the typical service ceiling is 56,000ft where the cockpit remains a shirt-sleeve comfortable, 10,000 feet.  

Northrop Grumman
Scaled Composites
Experimental High Altitude, Certified Experimental Research and Development
12.2 hours (payload and weather dependent)
Useful Payload: 
7,400 lbs
Gross Take-off Weight: 
14,200 lbs
Onboard Operators: 
Max Altitude: 
63,000 feet
Air Speed: 
330 knots
3,100 Nmi
28Vdc, 115Vac single phase 60Hz and 115Vac 3-phase 400Hz
Point(s) of Contact: 

Mike Cropper

Work: (757) 824-2140

Shane Dover

Work: (757) 864-2543
Mobile: (757) 894-2826
Fax: (757) 864-8549