The flight of the Lockheed Martin high-altitude long endurance-demonstrator (HALE-D) airship ended after less than three hours last week in a forced landing. Two days later, much of it was destroyed by a ground fire during recovery operations. The HALE-D was the first of three lighter-than-air vehicles due to fly this year with Pentagon funding, as the U.S. explores new means of providing persistent intelligence, surveillance and reconnaissance (ISR) and communications coverage over areas of conflict.

Lockheed Martin said that the remotely controlled HALE-D was launched successfully from the company’s Akron, Ohio, facility on July 27. But “a technical anomaly” prevented the airship reaching 60,000 feet as planned. It had ascended to 32,000 feet when the flight was cut short.

The 240-foot long airship made “a controlled descent” to land in a heavily wooded area in southwestern Pennsylvania, a spokesman for the Mission Systems and Sensors (MS2) division of Lockheed Martin told AIN. Some parts were removed before the fire, he added, but the envelope consisting of high-strength fabric and solar panels was mostly consumed by flames.

Dan Schultz, vice president ship and aviation systems for MS2, said, “We demonstrated a variety of advanced technologies, including launch and control of the airship, communications links, unique propulsion system, solar array electricity generation, remote piloting communications and control capability.”

But the U.S. Army Space and Missile Defense Command (USASMDC), sponsor of the HALE-D, was expecting a flight of up to two weeks at 60,000 feet to explore long-endurance station-keeping by means of two 2kW electric motors powered by thin-film solar cells and rechargeable lithium-ion polymer batteries. The HALE-D was a subscale prototype for the much larger and multi-mission high-altitude airship (HAA) project, which was originally conceived by the U.S. Missile Defense Agency.