The first Advanced Extremely High Frequency (AEHF) satellite is in thermal vacuum testing, Lockheed Martin Corp. [LMT] announced today.

The military communications satellite is in tests at the Lockheed facilities in Sunnyvale, Calif.

The Air Force AEHF system will provide global, highly secure, protected, survivable communications for the armed forces.

One of the most significant program milestones, thermal vacuum testing will verify AEHF spacecraft functionality and performance in a vacuum environment where the satellite is stressed at the extreme hot and cold temperatures it will experience in space throughout its 14-year design life.

AEHF thermal vacuum testing is conducted in the Lockheed Dual Entry Large Thermal Altitude (DELTA) chamber and is one of several critical environmental test phases that validate the overall satellite design, quality of workmanship and survivability during space vehicle launching and on-orbit operations.

Following completion of the tests in late July, Lockheed, the prime contractor, and Northrop Grumman Corp. [NOC] unit Space Technology at Redondo Beach, Calif., the payload supplier, will perform environmental test data analysis and remaining integration and test activities to prepare the vehicle for flight.

The spacecraft is planned for delivery to the Air Force early next year for launch aboard an Atlas V launch vehicle.

A single AEHF satellite will provide greater total capacity than the entire Milstar constellation currently on-orbit. Individual user data rates will be five times improved. The higher data rates will permit transmission of tactical military communications, such as real-time video, battlefield maps and targeting data. In addition to its tactical mission, AEHF will also provide the critical survivable, protected, and endurable communications to the National Command Authority including presidential conferencing in all levels of conflict.

Lockheed Martin is currently under contract to provide three AEHF satellites and the mission control segment to the Military Satellite Communications Systems Wing, located at the Space and Missile Systems Center at Los Angeles Air Force Base, Calif. The program is in the early stages of adding a fourth spacecraft to the planned constellation.