THE ORBITAL SCIENCES (OSC) Pegasus XL air-launched booster was used successfully to place the first two of the company's Orbcomm communications satellites into 728km (390nm) circular orbit on 3 April.
OSC's Microlab 1 research satellite, a smaller version of Orbcomm's MicroStar standard satellite bus equipped with NASA and National Science Foundation experiments, was also placed into orbit.
The Orbcomm satellites "...are poised to begin a global revolution in low-cost personal communications", says OSC. Through a planned 26-satellite constellation to be completed by 1997, customers round the world will be provided with messaging and position-determination services (Flight International, 5-11 January 1994).
OSC's MicroStar satellite constellation deployment sequence was used to place the satellites into different orbits. The first Orbcomm was released from the XL's third stage in a southerly direction after orbit was achieved. The Pegasus' attitude was then adjusted, facing to the north for the release of the Orbcomm 2. The Microlab was deployed following another manoeuvre.
The first successful launch of a Pegasus XL since the failure of the maiden flight in June 1994 took place from an altitude of just under 40,000ft (12,200m), 80km west of the coast of California. The OSC Lockheed L-1011 carrier aircraft had taken off from Vandenberg AFB.
The XL is a stretched version of the original Pegasus vehicle, which has been flown on four successful and two partially successfully launches since 1990.
Source: Flight International
