NASA is planning 24h-plus endurance flight tests of the solar-powered, remotely piloted Helios flying wing after a successful 16h 55 min flight over the Pacific in mid-August when it set a new world record altitude of 96,500ft (29,430m).

The AeroVironment-built flying wing, which measures 75.3m (247ft) in span, is powered by 14 electrically driven propellers supplied with energy from 62,000 solar panels. Developed and managed under NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project, the Helios high-altitude test was intended to demonstrate the viability of long-endurance, solar-powered unmanned air vehicles to perform missions such as environmental monitoring, atmospheric sampling and communications relay.

The record flight attempt, which was delayed two days for final checks and to allow high cirrus clouds to disperse, was made from the US Navy Pacific Missile Range site on Kauai, Hawaii. Flying at a maximum speed of 21kt (39km/h), the craft passed the altitude record for propeller-driven aircraft at 80,200ft and the 85,068ft record for sustained horizontal flight.

Source: Flight International