Charlie Hall and his Pioneer Project team were very experienced in mission operations. They had their own Mission Operations Center at the Ames Research Center in Sunnyvale and had experience dating back to Pioneers 6-9 in the 1960s and Pioneer 10 and 11 that were launched in 1972-73 and flew the first missions to Jupiter and Saturn. They relied upon the JPL DSN for tracking and communicating with the spacecraft, and JPL orbit determination capabilities, but were otherwise entirely self sufficient. They looked forward to their first missions to Venus with the Pioneer Venus Orbiter and Multiprobe.
ARC realized that successful missions operations would depend upon a detailed knowledge of the spacecraft and its characteristics that would have to be provided by the spacecraft contractor. Accordingly ARC issued Contract No. NAS 2-9366 to Hughes Aircraft in 1976 to provide Operational Characteristics Documents for both the Pioneer Venus Orbiter and Multiprobe. I was given responsibility for this contract. My first task was to find someone to take the lead for this monumental task. Since the project team was extremely busy at this time I had to look elsewhere. I consulted Perry Ackerman and he suggested Ken Filetti. I did not know Ken at this time, but I didn’t have a lot of options, so Ken it was,
Ken set to work, developed a plan, and began. The Orbiter Operational Characteristics document came together between September 1976 and June 1977 and was published on February 28, 1978. It describes the orbiter system and interfaces, each subsystem, its operating modes, and mission operations in a total of 963 pages. The authors of this document were Bill Butterworth, Dick Daniel, Bob Drean, Ken Filetti, Jack Fisher, Larry Nowak, Joe Porzucki, Jerry Salvatore, and George Tadler of systems engineering and Fred Barker from propulsion.
The Multiprobe document was prepared between September 1976 and May 1978, and was published on May 22, 1978 in three volumes consisting of 1002 pages and covering the Multiprobe, Large Probe and Small Probes. The authors were again Bill Butterworth, Dick Daniel, Bob Drean, Ken Filetti, Jack Fisher, Larry Nowak, Joe Porzucki, Jerry Salvatore, George Tadler and Fred Barker with the addition of Fred Richardson and Jan Sikola.
Both missions were very successful: the Multiprobe mission was shorter and ended with the successful entries of the Bus, Large Probe and three Small Probes on December 9, 1978 while the Orbiter mission, through careful propellant management, was extended to October 8, 1992, a total of more than 14 years. I am grateful to Ken Filetti and the authors of these documents for their contributions to the success of the Pioneer Venus missions.