(08/12/1999) --- A C-5 air cargo plane lands at Kennedy Space Center carrying the payload flight hardware for the Third Hubble Space Telescope Servicing Mission (SM-3A). The hardware will be taken to the Payload Hazardous Servicing Facility for final testing and integration of payload elements. Mission STS-103 is a 'call-up' mission which is being planned due to the need to replace portions of the Hubble's pointing system, the gyros, which have begun to fail. Although Hubble is operating normally and conducting its scientific observations, only three of its six gyroscopes are working properly. The gyroscopes allow the telescope to point at stars, galaxies and planets. The STS-103 crew will not only replace gyroscopes, it will also replace a Fine Guidance Sensor and an older computer with a new enhanced model, an older data tape recorder with a solid state digital recorder, a failed spare transmitter with a new one, and degraded insulation on the telescope with new thermal insulation. The crew will also install a Battery Voltage/Temperature Improvement Kit to protect the spacecraft batteries from overcharging and overheating when the telescope goes into a safe mode. Launch of STS-93 is currently targeted for Oct. 14 but under review, pending the launch date of a prior mission, STS-99, also under review