# JSC News Release Log 1990/90-028

Flight Control of STS-31
Flight control for STS-31, the thirty-fifth voyage of the Space Shuttle, will follow the same procedures and traditions common to all-U.S. manned space flights since the Mission Control Center was first used in 1965.
Responsibility for conduct of the mission will revert to the Mission Control Center (MCC) in Houston once Discovery's two solid rocket boosters ignite. Mission support will begin in the MCC about five hours prior to launch and will continue around-the-clock through the landing and post-landing activities.
The mission will be conducted from Flight Control Room One (FCR-1) on the second floor of the MCC located in Bldg. 30 at Johnson Space Center.
Three teams of flight controllers will alternate shifts in the control center and in nearby analysis and support facilities. The handover between each team takes about an hour and allows each flight controller to brief his or her oncoming colleague on the course of events over the previous two shifts. Change-of-shift press conferences with offgoing flight directors generally take place 30 minutes to an hour after the shift handovers have been completed.
The three flight control teams are referred to as the Ascent/Entry/Orbit 1, Orbit 2 and Planning teams. Generally, the STS-31 crew's working day is split between the Orbit 1 and Orbit 2 shifts.
The ascent phase will be conducted by Flight Director Ronaid D. (Ron) Dittemore. Once Discovery is in orbit, this shift is known as Orbit 1 and will be headed by STS-31 Lead Flight Director William D. {Bill) Reeves. Some of the flight control positions will be staffed by the same personnel for both Ascent/Entry and Orbit 1 operations. Other positions will alternate between specialists in launch/landing activities and orbital operations. On the final day of the mission, Flight Director N. W. (Wayne) Hale will head the Entry team for Discovery's landing phase. As is the traditional practice, Hale ​also will lead the Orbit 1/Entry team the day before landing to oversee entry preparations.
The Orbit 2 team will be led by Flight Director James M. (Milt) Heflin. The Orbit 2 team will be prime for EVA operations should a spacewalk by crew members Dr. Kathryn Sullivan and Bruce McCandless become necessary. The Orbit 1 team will be prime for Hubble Space Telescope deploy operations.
The Planning Team, which for the most part operates during the crew's sleep shift, will be led by Flight Director Alan L. (Lee) Briscoe.
MCC Positions and Call Signs for STS-31
STS-31 will mark the first mission since the early days of the Shuttle program in which the responsibility for electrical and environmental systems will be divided into two console positions, called EFECOM and EGIL. The position known as EECOM--for Environmental Engineer and Consumables Manager--will continue to have responsibility for the life support systems aboard Discovery, as well as cabin pressure, active and passive thermal control systems (such as the Flash Evaporator System), and the Management of the supply and waste water tanks.
The EGIL position--for Electrical Generation and Illumination--has responsibility for operation of the three fuel cells, the DC buses and AC power inverters, and the overall electrical system aboard the Orbiter. EGIL also will be responsible for the Master Caution and Warning System.
The flight control positions in the Mission Control Center, their call signs and their functions are:
Flight Director (FLIGHT)
Has overall responsibility for the conduct of the mission.
Spacecraft Communicator (CAPCOM)
By tradition an astronaut; responsible for all voice contact with the flight crew.
Flight Activities Officer (FAO)
Responsible for procedures and crew timelines; provides expertise on flight documentation and checklists; prepares messages and maintains all teleprinter and/or Text and Graphics System traffic to the vehicle.
Phase Specialist (PROCEDURES)
This is a speciality position which sometimes operates at ​the FAO console. The Phase Specialist offers expertise for the Flight Director in specific procedures required during complex operations.
Integrated Communications Officer (INCO)
Responsible for all Orbiter data, voice and video communications systems; monitors the telemetry link between the vehicle and the ground; oversees the uplink command and control processes.
Flight Dynamics Officer (FDO)
Responsible for monitoring vehicle performance during the powered flight phase and assessing abort modes; calculating orbital maneuvers and resulting trajectories; and monitoring vehicle flight profile and energy levels during reentry.
Guidance Procedures Officer (GPO)
Responsible for the onboard navigational software and for Maintenance of the Orbiter's navigational state, known as the state vector.
Trajectory Officer (TRAJECTORY)
Also known as "TRAJ," this operator aids the FDO during dynamic flight phases and is responsible for maintaining the trajectory processors in the MCC and for trajectory inputs made to the Mission Operations Computer.
Environmental Engineer & Consumables Manager ({EECOM)
Responsible for all life support systems, cabin pressure, thermal control and supply and waste water management; manages consumables such as oxygen and hydrogen.
Electrical Generation and Illumination Officer (EGIL)
Responsible for power management, fuel cell operation, vehicle lighting and the master caution and warning system.
Payloads Officer (PAYLOADS)
Coordinates all payload activities; serves as principal interface with remote payload operations facilities.
Data Processing Systems Engineer (DPS)
Responsible for all onboard mass memory and data processing hardware; monitors primary and backup flight software systems; manages operating routines and multi-computer configurations.
​Propulsion Engineer (PROP)
Manages the reaction control and orbital maneuvering thrusters during all phases of flight; monitors fuel usage and storage tank status; calculates optimal sequences for thruster firings.
Booster Systems Engineer (BOOSTER)
Monitors main engine and solid rocket booster performance during ascent phase.
Guidance, Navigation & Control Systems Engineer (GNC)
Responsible for all inertial navigational systems hardware such as star trackers, radar altimeters and the inertial measurement units; monitors radio navigation and digital autopilot hardware systems.
Ground Controller (GC)
Coordinates operation of ground stations and other elements of worldwide space tracking and data network; responsible for MCC computer support and displays.
Maintenance, Mechanical, Arm & Crew Systems (MMACS)
Formerly known as RMU; responsible for remote manipulator system; monitors auxilliary power units and hydraulic systems; manages payload bay and vent door operations.
Rendezvous Guidance and Procedures Officer (RENDEZVOUS)
Monitors onboard navigation of the Orbiter during rendezvous operations and advises the control team on the rendezvous profile. Should a contingency revisit to HST become necessary on this flight, the Rendezvous position would be activated.
Flight Surgeon (SURGEON)
Monitors health of flight crew; provides procedures and guidance on all health-related matters.
Public Affairs Officer (PAO)
Provides real-time explanation of mission events during all phases of flight.
STS-31 Flight Control Team Staffing :
| Position | Ascent/Entry | Orbit 1 | Orbit 2 | Planning |
| FLIGHT | Ron Dittemore Wayne Hale | Bill Reeves | Milt Heflin | Lee Briscoe |
| CAPCOM | Steve Oswald Mike Baker | Story Musgrave Don McMonagle | James Voss Ken Bowersox | Kathy Thornton |
| FAO | Nancy Jackson | Nancy Jackson | Neil Woodbury | Tony Griffith |
| PROCEDURES | / / / / / | Eric Joern | / / / / / | Mike Hurt |
| INCO | Edgar Walters | Edgar Walters | Jay Conner | Joe Gibbs |
| FDO | Brian Perry Bruce Hilty | Philip Burley | Keith Fletcher | Richard Theis |
| TRAJ | Matt Abbott William Tracy | William Tracy | Debbie Langan | Dan Adamo |
| GPO | Jeff Bertsch John Turner | John Malarkey | Andy Dougherty | / / / / / |
| EECOM | Dave Herbek | Dave Herbek | Leonard Riche | Peter Cerna |
| EGIL | Ray Miessler | Ray Miessler | Robert Floyd | Charles Dingell |
| PAYLOADS | Nellie Carr | Nellie Carr | Jeffrey Hanley | Cheryl Moinar-Boyd |
| DPS | Terry Keeler | Terry Keeler | Davud Tee | Gloria Araiza |
| PROP | Anthony Ceccacci | Anthony Ceccacci | Matthew Barry | Jeff Detroye ​ |
| BOOSTER | Thomas Kwiatkowski | / / / / / | / / / / / | Ken Dwyer |
| GNC | David Miller | David Miller | Edward Trlica | Chuck Alford |
| GC | Norm Talbott Larry Poy | John Wells Joe Acquino | Chuck Capps Per Barsten | Victor Lucas Bob Reynolds |
| MMACS | Paul Dye | Paul Dye | Robert Doremus | Ledessa Hicks |
| SURGEON | Jeff Davis | Jeff Davis | Philip Stepaniak | / / / / / |
| PAO | Billie Deason | Jeff Carr | Kyle Herring | James Hartsfield |
* ↑ Ascent
* ↑ Entry
* ↑ Prime
* ↑ Backup
* ↑ Pre-Launch