STS-43 TDRS-E / IUS is deployed from OV-104's payload bay (PLB)

STS043-72-059 (2 Aug 1991) --- The Tracking and Data Relay Satellite (TDRS-E), leaves the payload bay of the earth-orbiting Atlantis a mere six hours after the Space Shuttle was launched from Pad 39A at Kennedy Space Center, Florida. TDRS, built by TRW, will be placed in a geosynchronous orbit and after on-orbit testing, which requires several weeks, will be designated TDRS-5. The communications satellite will replace TDRS-3 at 174 degrees West longitude. The backbone of NASA's space-to-ground communications, the Tracking and Data Relay satellites have increased NASA's ability to send and receive data to spacecraft in low-earth orbit to more than 85 percent of the time. The five astronauts of the STS 43 mission are John E. Blaha, mission commander, Michael A. Baker, pilot, and Shannon W. Lucid, G. David Low, and James C. Adamson, all mission specialists.