Stratospheric Flight: Solar-Powered Airship Sets Flight Record

US aerospace startup Sceye has covered more than 10,300 km with its HAPS SE2 (High-Altitude Platform Systems – HAPS) from New Mexico to the coast of Brazil. The solar-powered stratospheric airship set a new flight record with a total flight time of twelve days. The airship is intended for future commercial use in telecommunications and environmental monitoring.

The HAPS SE2 is approximately 82 m long and consists of a helium-filled structure. The outer skin is made of Sceye Skin, an extremely tear-resistant, UV- and ozone-resistant, and lightweight material developed by Sceye itself. The stratospheric airship, which is designed to remain in a fixed position at an altitude of about 20 km, is powered by an electric motor with a propeller at the rear. Solar cells are mounted on the top of the airship. Sceye does not provide exact details about the solar modules but reveals that the lithium-sulfur batteries used for storing solar energy have a specific energy of 425 Wh/kg.

The twelve-day test flight began on March 25 as part of an endurance program, as Sceye announced on Monday. The landing was controlled and took place as planned on April 6 in international waters off the coast of Brazil.

Constant Altitude and Position

During this time, the stratospheric airship covered approximately 10,300 km and crossed the area between New Mexico and the Brazilian coast at altitudes exceeding 15,850 m. The HAPS SE2 repeatedly remained stationary over selected areas in the stratosphere for a total of 88 hours. The airship remained in a fixed position over New Mexico for approximately a full day-night cycle and for three consecutive days off the coast of Brazil.

Throughout this period, the airship maintained its altitude and position solely through its solar power supply. The batteries of the HAPS SE2 were recharged during the day to ensure sufficient energy for continuous flight operations at night. The pressure system of the flight system could be kept constant for the entire duration, Sceye writes.

Sceye recorded data during the endurance flight. The company now intends to use the data analysis to gain further insights for the quickest possible commercial deployment of the stratospheric airship. A first pre-commercial test is already planned for the summer of 2026. The HAPS SE2 will then establish a backhaul connection to the core network of the Japanese investment holding Softbank in Japan.

The HAPS SE2 is primarily intended for use in communications. The solar-powered airship is designed to remain in position in the stratosphere for an extended period, with Sceye mentioning months to up to a year, and supply an area with broadband internet. This allows areas without terrestrial communication structures, or those damaged by disasters, to be supplied with broadband communication. Furthermore, with appropriate sensors, the HAPS SE2 can also conduct environmental observations from high altitudes.

(olb)