Command and data subsystem for the Seawinds instrument on Quickscat spacecraft

The loss of the ADEOS I spacecraft brought an abrupt end to the ocean wind scatterometer data from orbit. The NSCAT instrument onboard the ADEOS I had provided valuable information to atmospheric scientists as well as weather forecasters. The next generation scatterometer, Seawinds, was scheduled for launch in August of 1999 onboard ADEOS II but was almost sure to be delayed due to the investigation of ADEOS I failure and the required modifications to ADEOS II. To fill the gap in the ocean wind data, NASA embarked on a fast track building of a spacecraft and instrument to bridge the gap between the NSCAT data and the projected launch and operation of Seawinds instrument. The total time allotted for acquisition of LV and Satellite, the development of the instrument and integration and test was one year, hence the name Quickscat. This paper describes the command and data systems for the instrument and describes how we were able to define and develop a new interface for the instrument and deliver within 3 months.