Tim Furniss/LONDON

NASA HAS FORMED a series of teams "...to address all aspects of its strategy for access to space", following the second failure on 22 June in two launches of the new Orbital Sciences (OSC) Pegasus XL. The Administration has four spacecraft due for launches on the Pegasus air-launched satellite booster within the next year.

The teams will review "near-term recovery for Pegasus-related missions already in the inventory, as well as long-term issues associated with the next-generation launch vehicles", says the space agency.

"NASA sees a serious shortage over the next few years of small launch-vehicle support for its scientific missions...there is a significant backlog...a situation that NASA cannot allow to continue," it says.

The agency expects to issue a Request for Information asking for expressions of interest from industry in providing alternate sources of small expendable and re-useable launchers in the "near and long term".

The immediate NASA missions - the high-energy transient experiment and Argentina's Satellite de Aplicaciones Cientificas; the total ozone monitoring spectrometer 1; the Submillimeter-Wave Astronomy Satellite; and Fast Auroral Snapshot explorer - have already been delayed by earlier Pegasus difficulties, particularly the failure of the first Pegasus XL in June 1994.

OSC says that the failure on 22 June was the result of an anomaly during second-stage separation, which hindered the guidance system. The US Air Force Space Test Experiment Platform 3 spacecraft was lost when safety officers destroyed the vehicle at T+2min20s over the Pacific Ocean.

In addition to the two XL failures, two of five original Pegasus models did not reach the correct orbits. The first Pegasus was flown in 1990. OSC has more than 15 outstanding payloads for the USAF and others, as well as commitments to launch a series of its own proprietary satellites, including the Orbcomm and Orbview.

The main benefactor of OSC's difficulties could be Lockheed Martin, which is preparing its LLV booster for its first flight from Vandenberg AFB, California. The company has captured NASA payloads - the Lewis and Clark - originally manifested on the Pegasus. The only other available US small-satellite booster, the Conestoga, is untested.

The Conestoga, developed by EER Systems, will have its first flight from Wallops Island, Virginia, later this month, carrying NASA's Commercial Experiment Transporter (Comet).

Source: Flight International