"6_2_2_3_7.TXT" (2383 bytes) was created on 01-02-89

STS-6

        On April 4, 1983, STS-6, the first Challenger mission, lifted off at
1:30 p.m. EST.  It was the first use of a new lightweight external
tank and lightweight SRB casings.

        The mission originally had been scheduled for launch on Jan. 30,
1983.  However, a hydrogen leak in one of the main engines was
discovered.  Later, after a flight readiness firing of the main
engines on Jan. 25, 1983, fuel line cracks were found in the other
two engines.  A spare engine replaced the engine with the hydrogen
leak and the other two engines were removed, repaired and reinstalled.

        Meanwhile, as the engine repairs were underway, a severe storm
caused contamination of the primary cargo for the mission, the first
Tracking and Data Relay Satellite (TDRS), while it was in the Payload
Changeout Room on the Rotating Service Structure at the launch pad.
This meant the satellite had to be taken back to its checkout
facility where it was cleaned and rechecked. The Payload Changeout
Room and the payload bay also had to be cleaned.

STS-6 carried a crew of four -- Paul J. Weitz, commander; Karol J.
Bobko, pilot; Donald H. Peterson and Story Musgrave, both mission
specialists.  Using new space suits designed specifically for the
Space Shuttle, Peterson and Musgrave successfully accomplished the
program's first extravehicular activity (EVA), performing various
tests in the payload bay.  Their space walk lasted for 4 hours, 17
minutes.

        Although the 5,000-lb. TDRS was successfully deployed from the
Challenger, its two-stage booster rocket, the Interim Upper Stage
(IUS), shut down early, placing the satellite into a low elliptical
orbit.  Fortunately, the satellite contained extra propellant beyond
what was needed for its attitude control system thrusters, and during
the next several months the thrusters were fired at carefully planned
intervals gradually moving TDRS-l into its geosynchronous operating
orbit thus saving the $100-million satellite.

        Other STS-6 cargo included three GAS canisters and continuation of
the Monodisperse Latex Reactor and the Continuous Flow
Electrophoresis experiments.

        Challenger returned to Earth on April 9, 1983, at 10:53 a.m. PST,
landing on Runway 22 at Edwards AFB.  It completed 80 orbits,
traveling 2 million miles in 5 days, 24 minutes, 32 seconds.  It was
flown back to KSC on April 16.