The Success of Intelsat VI F-3 Reboost Mission–Chuck Rubin May 26, 1992—Transcribed by Faith MacPherson

Editors Note: Chuck Rubin was the Program Manager for the Hughes Intelsat VI Reboost Mission and wrote this IDC after the successful conclusion of the mission. My thanks to Joan Tarro for providing this document.

The complete mission is described in Intelsat VI F-3 Recovery.

The Intelsat VI F-3 Reboost Mission turned out to be a space spectacular and a resounding success. The F-3 satellite has now been raised to synchronous orbit with the solar panel and all antennas deployed. The satellite will become operational in late June with enough propellant for a 12-year orbit maneuver lifetime, well beyond the 10 year goal established in the Reboost Contract.

We should all be proud of the Hughes contribution to the success of this mission. Our role was extremely significant and covered the full range of activities:

  • The design and development of all the new hardware (cradle, PKM, docking equipment, etc.) except for the NASA Capture Bar
  • Launch vehicle integration activities with NASA
  • Mission planning for all mission phases
  • Lead role in critical rendezvous operations
  • Support of all other operations at Intelsat control center in Washington and NASA mission control in Houston

Unfortunately, the extent of our contribution has not received the attention it deserves primarily because the media has played down our role almost to the point of omission. So, before I offer my commendations to the Reboost team, I’d like to quickly summarize for you some of the Hughes achievements in this mission and to correct some misinformation that has been printed in the press.

Our mission began three hours after liftoff on May 7 with a series of maneuvers on the F-3 satellite to bring it down from its 300 n mi storage orbit to the 197 n mi rendezvous orbit. During this critical 46 hour period our team in Washington was in constant communication with the NASA flight dynamics group in Houston to ensure proper coordination between the two maneuvering spacecraft (the shuttle and the F-3). The Hughes orbital software and the Hughes team took the lead role and pulled off a pinpoint targeting of the satellite to the center of the “control box”. As a result, the shuttle needed less propellant to accomplish the rendezvous making it possible to add an extra day of EVA to the overall mission.

After we “safed” the satellite and spun it down for capture, Pierre Thuout began his two days of frustrating attempts to attach the Capture Bar to the satellite. It is now generally felt that his difficulty was caused by the complexity and balkiness of the Capture Bar combined with the inability of the satellite simulator to adequately represent the sensitivity of the satellite to disturbing forces in a 0-g environment. Both the Capture Bar and the training simulator were the responsibility of NASA. In addition, I want to make it clear that a statement carried in the press that the capture problem was due to Hughes providing inaccurate data to NASA is completely incorrect. The person at NASA who supposedly made that statement now says he was misinterpreted and really meant to focus on the deficiencies of the training simulator.

The efforts of the attitude control team in Washington should be mentioned at this point. Due to the multiple capture attempts, it was necessary to repeatedly restore the satellite to a low nutation state for ease of capture. Consequently, each time the satellite was significantly disturbed, it was necessary to spin it up to 10 rpm, remove the nutation and spin it down to as low as 0.25 rpm. Achieving low nutation (<4 degrees) at such low spin rates was a major accomplishment; so was recovering the satellite from the 70-degree nutation induced during the final attempt with the capture bar. NASA gave the team high praise for their skill in controlling the satellite.

Our hardware didn’t come onto the space walk scene until after the satellite was successfully captured and grappled to the orbiter’s remote manipulation arm during the historic three man EVA. Once the satellite was finally brought down on top of the docking adapter/perigee stage, the astronauts began the mating process which involved all Hughes hardware. And to the credit of the Hughes team, it all performed flawlessly. The mechanical attachment was made using four pyro releasable docking clamps, each having a specially developed load limiting clutch to prevent over-torquing the clamping bolt. The electrical attachment was accomplished when the crew mated two umbilical devices. Electrical continuity was then verified by the activation of three LEDs on the two docking adapter electronic units called SBUs, designed and built by Hughes specifically for the Reboost Mission. The entire mating process went very smoothly and took less than an hour to complete.

The subsequent deploy of the combined satellite and perigee stage encountered some difficulty, however, due to incorrect deploy procedures which had not been updated by NASA to reflect a wiring design change. An alert ground crew at NASA/JSC quickly caught the problem and sent the corrected procedure up to the crew. A few minutes later the Lockheed provided Super Zip at the interface of our cradle and perigee stage was successfully fired. Separation occurred using a set of twelve canted separation springs which provided both a translation and rotation as the spacecraft left the orbiter bay.

Approximately fifteen hours later, the redundant SBUs received ground commands through the satellite umbilicals to arm the Safe & Arm units, fire the perigee kick motor (PKM), separate the burned out motor stage and, finally, separate the docking adapter. The F-3 satellite was then back to its normal transfer orbit configuration on its way to geosynchronous orbit.

This success could not have been accomplished without the outstanding efforts of the Hughes Reboost team. Although the group as a whole deserves much praise, there are a few individuals in your organization which I would like to single out for the special contribution they made to the program:

DIVISION 4K PERSONNEL/CONTRIBUTION

Jason Endo for his excellent task management of the 4K team as well as his extremely helpful support to the Program Office in his role as Assistant Program Manager.

Chuck Maloney for the key roles he played in leading the design effort on all of docking equipment, in his active participant as a member of the WETF diving team to provide technical assistance to the astronauts during their water tank weightless training, and in his dedication and meticulous efforts as the Vehicle Engineer both at El Segundo and the Cape.

Mike Nolan for his creative and thorough effort in the design and development of a new load limiting clutch for the docking clamps.

Dave Esposto, Glen Austin and Frank Freres for their combined efforts leading to the development of a unique cradle structure that was totally fabricated and assembled by an outside vendor, a first for Hughes for a structure this large.

Jeff Turney for his contribution to the free-float rollover process to rotate the cradle/perigee stage into the J-hooks at the VPF facility in Florida and for his excellent management of the GSE team.

Joan Tarro for her dedication and excellent secretarial support throughout the duration of the Reboost Program.

DIVISION 4J PERSONNEL/CONTRIBUTION

Russ Piombino for his exemplary project management of the Staging and Boost Unit (SBU) design and development effort.

Mike Cohn for his technical guidance during the design phase.

Alex Mihich for his critical role in circuit design and unit test.

Mark Wolinsky for the design of the unit tester and his support during unit testing.

Gary Duncan for his efforts in the product design and development of the shock isolation system.

DIVISION 4M PERSONNEL/CONTRIBUTION

SYSTEM ENGINEERING

Dennis Nell for his role in the development of requirements for the SBU and his diligent oversight of the design and testing activities, for his invaluable support to the NASA safety process, and for his support during mission operations.

Willie Magee and Tom Lundregan for their role in preparing the exacting documents required for the Safety Review process.

Mark Altobelli for his role in mission planning and his outstanding effort in the development and generation of the Sequence of Events Document and the timely coordination instructions during mission operations.

Don Patterson for his management of the Launch Vehicle Integration task and for his excellent working relationship with NASA.

STRUCTURAL MECHANICS

Sam Bassily for his excellent project management and his invaluable expertise which led to a very efficient cradle design to analyze and manufacture and to a trouble-free static test.

Bob Holman for his tireless effort to lead the stress activity on the docking equipment.

Ray Ng for his accurate modeling and stress analysis of the cradle and for his role in the planning and execution of the static test.

Fran Gulick for his rapid turnaround on the many coupled loads analyses that were conducted on this program.

THERMAL CONTROL

Greg Reynolds for his task management and his thoroughness in the analysis of the thermal loading and the design of the thermal hardware and for his support in Washington during mission operations.

Stan Banash for his analysis support, and the generation of the final thermal analysis report, and for his support at NASA/JSC during mission operations.

INTEGRATION AND TEST/LAUNCH OPS

Bill Scanlon for his excellent task management and his “take charge” attitude which kept his effort on schedule and in budget.

Ralph Yoak and Bill Amlotte for their joint efforts during the integration and test phase to ensure thorough checkout and test of all hardware both at El Segundo and Florida.

Paul Ely for his efforts on the planning and management of the launch operations interfaces at the Cape.

Carl Fjedelem for his supervisory role of the mechanical technicians and the excellent job his team did in integration and mechanical operations such as the critical rollover for VPF operations.

MASS PROPERTIES

Greg Johns for his accurate mass property tracking and generation of status reports.

PROPULSION

Phil Donatelli for his expert handling of the PKM procurement from CSD and his support in Washington during mission operations.

John Ellison for his support during the Safety Review process, his development of an improved propellant performance predictor and his support in Washington during mission operations.

CONTROLS

Loren Slater for his conscientious and responsive support throughout the program and for his invaluable expertise which greatly aided the analysis and mission planning activities, and for his role as ADCS team leader in Washington during mission operations.

MISSION ANALYSIS/OPERATIONS

Jerry Salvatore for his lead role in mission planning and for his excellent performance during the mission operations, especially during the rendezvous phase.

Murray Thompson for the modification of the Hughes orbital software and his expert use of the S/W during mission operations in Washington.

Mary Cafasso and Mery Pinheiro for their expertise in support of the rendezvous/orbits team during mission operations in Washington.

Carolyn Shallon for her updates to the software and her support of the mission operations in Washington.

DIVISION 40 PERSONNEL/CONTRIBUTION

Dave Duckworth for his thorough and responsive efforts as the program product assurance representative.

DIVISION 43 PERSONNEL/CONTRIBUTION

Doug Meyer for his outstanding effort as Business Manager and his willingness and support to help out no mater how time consuming or menial the task.

Please extend my thanks and appreciation to all who participated in the Reboost program.

Signed by C.P. Rubin

 

 

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