AeroVironment Helios Prototype

AeroVironment · United States · first flew 1999 · reconnaissance aircraft

The AeroVironment Helios Prototype was a NASA-funded solar-powered unmanned flying wing with a span of 75.3 m, designed to demonstrate sustained high-altitude flight using solar energy. It set an altitude record of 29,524 m for propeller-driven aircraft in 2001.

Recognition (WEFT)

W — WingsHigh-mounted, straight
E — Engines4 × electric, wing-mounted
F — FuselageUnmanned solar-electric flying wing — no fuselage
T — TailNo tailplane

WEFT is AircraftIQ's four-point recognition method — how it works.

Spot it by:

An extreme-span flying wing with no fuselage or tail, multiple small propellers distributed across its upper surface, and a pronounced dihedral giving the wing a curved arc in flight.

Specifications

Figures are for the representative variant described above; marks differ. See how AircraftIQ sources figures.

History

Helios was developed by AeroVironment under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) programme as an evolution of the Pathfinder and Centurion designs. Powered by up to 14 electric motors driven by solar cells, it achieved remarkable altitude records before a structural failure caused its loss over the Pacific Ocean in 2003.

Variants

The Helios flew in two configurations: a high-altitude version and a high-endurance version with hydrogen fuel cells; the aircraft was destroyed before the second configuration was fully demonstrated.

Where you'll see it

Operated exclusively as a NASA research demonstrator; no operational or military service.

Related aircraft

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