Tim Furniss/LONDON

A McDonnell Douglas Delta 2 rocket launched from Cape Canaveral on 23 July carried the first Navstar GPS 2R global- positioning-system-satellite to reach orbit. It is the 42nd in the Navstar series to be launched.

The original 2R spacecraft, built by Lockheed Martin, was destroyed in the explosion of a Delta rocket over Cape Canaveral, in Florida, in January. The 2R craft and its 18 successor satellites will be able to perform six months' autonomous operations without ground-control corrections.

In another launch from Canaveral, on 28 July, an ILS International Launch Services Atlas 2AS booster lofted Japan's Superbird C communications satellite into orbit.

An ILS Proton booster will launch the PanAmSat 5 communications satellite from the Baikonur Cosmodrome on 5 August, while the PanAmSat 6 is due for an Ariane 44P launch on flight V98 from the Guiana Space Centre, Kourou, French Guina, on 8 August.

Meanwhile, Arianespace has won three more contracts to launch Mexico's Hughes-built Morelos 3 communications satellite in 1998 and two CD Radio spacecraft being built by Space Systems Loral.

The CD craft will be lifted by an Ariane 5 booster in 1999 under a service to CD Radio of Washington DC, partially financed through a loan from Arianespace Finance.

This will be the first use of the supplementary services which were recently established by the European launcher organisation. It is also the first contract to be signed by Jean Marie Luton, Arianespace's new chairman and chief executive.

At Vandenberg AFB, California, a Titan 4 booster is being prepared for launch of a US reconnaissance satellite into polar orbit.

The launch was called off on 16 July, when nitrogen tetroxide leaked from the booster's thrust-vector control system, resulting in a partial evacuation of the base.

Meanwhjile, Russia was to launch the manned Soyuz TM26 spacecraft from Baikonur on 5 August to dock with the Mir space station (Flight International, 30 July-5 August), while at the Kennedy Space Center in Florida, the Space Shuttle STS85/Discovery is being prepared for its 8 August flight on a ten-day Earth-observation science mission.

The STS85 will be the first Shuttle to have new on-board flight software which will allow future missions to carry more payload into orbit, especially to support the construction and operation of the International Space Station.

On the STS85, the Lockheed Martin 01-26 software improvements will maintain a constant pitch rate for the Discovery at solid-rocket-booster (SRB) separation.

The most radical change to the Shuttle ascent as a result of the new software will be the roll of the Shuttle stack to a "heads-up" position after SRB separation. Previously, the orbiter has remained "heads down" from just after lift-off to main engine cut-off.

On the STS86 - a flight to the Mir scheduled for September - the roll manoeuvre will begin at an altitude of 350,000ft (107,000m), to permit earlier communications with the Tracking and Data Relay Satellite system.

Source: Flight International

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