Mission Control Center

Flight Controller Positions

Placed atop each console are initials or abbreviated names for each console's function. Each console also has a "call sign," the name the controller uses when talking to other controllers over the various telephone communication circuits. In some cases, console names or initials are the same as the call signs. Mission command and control positions, their respective initials, and call signs are listed below.

1.Public Affairs Officer (PAO), provides mission commentary to supplement and explain air-to-ground transmissions and flight control operations to the news media and the public.

2.Mission Operations Directorate Manager (MOD), provides a link from the Flight Control Room to top NASA and JSC Missions Operations Directorate management.

3.Russian Interface Operator (RIO), serves as the primary interface between the U.S. and Russian control teams. The RIO updates the Russian team on shuttle related activities and issues, and relays messages from the Russian team to the U.S. team.

4.Surgeon (Surgeon), monitors crew activities, coordinates medical operations flight control team, provides crew consultations, and advises flight director of the crew's health status.

5.Integrated Communications Officer (INCO), plans and monitors in-flight communications and instrumentation systems configuration.

6.Flight Director (FD) call sign "Flight," serves as leader of the flight control team, and is responsible for overall shuttle mission and payload operations and all decisions regarding safe, successful flight conduct.

7.Spacecraft Communicator (CAPCOM) call sign "Capcom," serves as primary communicator between flight control and astronauts. The initials are a holdover from earlier manned flight, when Mercury was called a capsule rather than a spacecraft.

8.Payload Deploy Retrieval (PDRS), monitors operation of the remote manipulator system.

9.Data Processing System Engineer (DPS), determines status of data processing system including the five onboard general purpose computers, flight-critical and launch data lines, the multifunction display system, mass memories, and systems-level software.

10.Payloads Officer (Payload), coordinates onboard and ground system interfaces between the flight control team and payload user, and monitors Spacelab and upper stage systems and their interfaces with the payload.

11.Flight Activities Officer (FAO), plans and supports crew activities, checklists, procedures and schedules, and plans/manages the attitude (orientation in space) of the vehicles.

12.Electrical, Environmental, Consumables Manager (EECOM), responsible for passive and active thermal control of the vehicle, cabin atmosphere control, avionics cooling, supply/waste water system management, and fire detection/suppression.

13.Propulsion Engineer (PROP), monitors and evaluates reaction control and orbital maneuvering propellants and other consumables available for maneuvers.

14.Guidance, Navigation, and Controls Systems Engineer (GNC), monitors all vehicle guidance, navigation, and control systems, notifies flight director and crew of impending abort situations, and advises crew regarding guidance hardware malfunctions.

15.Maintenance, Mechanical, Arm, and Crew Systems (MMACS), call sign "Max," monitors operation of the orbiter's structural and mechanical system, and follows use of onboard crew hardware and in-flight equipment maintenance.

16.Electrical Generation and Illumination Engineer (EGIL), monitors electrical systems, fuel cells and associated cryogenics, ac and dc power buses, vehicle pyrotechnics, and lighting, and hardware caution and warning systems.

17.Flight Dynamics Officer (FDO), call sign "Fido," plans maneuvers and monitors trajectory in conjunction with Guidance officer.

18.Rendezvous.

19.Ground Controller (GC), directs maintenance and operation activities affecting Mission Control hardware, software and support facilities, coordinates the Ground Space Flight Tracking and Data Network (GSTDN) and the Tracking and Data Relay Satellite System (TDRSS) with Goddard Space Flight Center.

20.Worldmap Screen.

21. TV Screen.

22. Mission Clocks/Telemetry Data. One of the most interesting of the FCR support facilities is the display/control system, a series of projection screens on the front wall of the FCR. These displays range from plotting charts that show the spacecraft's location to actual television pictures of activities inside the Shuttle as well as views of Earth, payload deployment/retrieval, and extravehicular activity (EVA) work by mission specialists. Other displays show such things as elapsed time after launch or time remaining before a maneuver or other event. Flight controllers base many of their decisions or recommendations on the information given by the display/control system. The real-time computer complex processes telemetry and tracking data to update controllers on Shuttle systems. Controllers can call up stored reference data based on simulated flights previously conducted as practice for the actual mission.

During missions on which a Spacelab module is carried in the orbiter's payload bay, an additional flight control position is Command and Data Management Systems officer (CDMS), responsible for data processing systems involving Spacelab's two major computers. In support of the Spacelab missions, additional responsibilities are borne by EECOM and EGIL in management of systems extended from the orbiter to the Spacelab. Power distribution (EGIL), life support, cooling, and cabin fans (EECoM) require more complex monitoring. Management of cryogens for fuel cells, performed by the EGIL, becomes a more significant duty for Spacelab missions because of the higher power levels used, and because of the additional Spacelab electrical systems to be monitored. The DPS controller works closely with the CDMS officers in monitoring additional displays covering nearly 300 items.

Information

Neil Armstrong, Commander Apollo 11 Lunar Lander: "Houston, Tranquility Base here. The Eagle has landed."

Those words, the first ever transmitted to Earth by a human being from the surface of the Moon, are testimony to the essential role played by the Mission Control Center at NASA's Johnson Space Center in Houston. The reply, the first ever heard by a man on the Moon, conveys the urgency that permeates the Mission Control during such moments:

Mission Control: "Roger, Tranquility, we copy you on the ground. You've got a bunch of guys about to turn blue. We're breathing again. Thanks a lot. "

Flight Controllers in the Johnson Space Center Mission Control Center (MCC) monitor the extravehicular activity (EVA) of astronaut on orbit. Since 1965, the Mission Control Center (MCC) has been the nerve center for America's manned space program. The men and women who work in Building 30 at the Johnson Space Center have been vital to the success of every manned space flight since Gemini 4. These teams of experienced engineers and technicians monitor systems and activities aboard spacecraft 24 hours a day during missions, using some of the most sophisticated communication, computer, data reduction, and data display equipment available. They watch every movement the crew and spacecraft make, double-check every number to be sure missions are proceeding as expected, and provide the expertise needed to deal with the unexpected. During the Mercury project, when mission control was at Cape Canaveral, capsules were controlled almost entirely from the ground. The capsule's manual control systems served in most cases as backups to the automated systems, and astronauts relied heavily on ground control for solutions to problems that arose. As spacecraft became more complex in the Gemini years, dependence on the new MCC in Houston lessened slightly. During Apollo, when distance and communications breaks made it necessary, some onboard systems became prime while others retained their reliance on MCC direction. The frequent missions of the Space Shuttle program require a new approach to flight control. Because there is more data to monitor than the crew has time to manage, the flight control team's main responsibility is evaluating the data to provide the crew with additional insight and aid it in managing the complex systems of the orbiter. From the moment the giant solid rocket boosters ignite at liftoff to the moment the landing gear wheels roll to a stop at the end of a mission, the MCC is the hub of communication and support for the Shuttle. The MCC's focal points are the two Flight Control Rooms, or FCRs (pronounced "Fickers"), where flight controllers get information from console computer displays or from projected displays that fill the wall at the front of the room. Almost everyone has seen the television pictures of MCC flight controllers working feverishly at their consoles, headsets in place. The MCC contains two functionally identical FCRs, one on the second floor and one on the third. Either FCR can be used for mission control, and often one team of flight controllers conducts an actual flight while a second team conducts highly realistic training, called a simulation or "sim" for short, for a future mission. Flight controllers who work in the FCRs represent only the tip of the staffing iceberg in the MCC. Each of the 15 to 20 flight controllers who sits at a console in the FCR has the help of many other engineers and flight controllers monitoring and analyzing data in nearby staff support rooms.

Supporting Cast

Multipurpose support room (MPSR) groups represent one support discipline and encompass planning and support functions. The MPSR groups provide replanning expertise, support FCR controllers with additional subsystem-level expertise, analyze system performance data, trend monitoring, etc., and respond quickly to any in-flight contingency. Operating in conjunction with the FCRs are Payload operations Control Centers (POCCs) from which the owners of payloads or experiments carried in the cargo bay of the orbiter can monitor and control their payloads. The Spacelab POCC, located at NASA's Marshall Space Flight Center in Huntsville, Alabama, is the site for continual monitoring and control of Spacelab experiments and other attached payloads. It is a command post, communications center, and data relay station for principal investigators, mission managers and their support staffs. All decisions about payload operations are made and coordinated with the mission flight director at the MCC in Houston, and then transmitted to the Spacelab or Shuttle crew. Free-flying systems deployed, retrieved, or serviced in Earth orbit by the orbiter are monitored by a POCC at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Private sector organizations as well as foreign governments maintain individual POCCs at locations of their choice for long-term control of free-flying systems. Payloads with distant destinations, such as those exploring other planets, are controlled from the POCC at NASA's Jet Propulsion Laboratory in Pasadena, California. For the Space Station era, a new five-story facility, the Space Station Control Center (SSCC), has been built. The SSCC will be the focal point for the coordination of operations aboard the Space Station and among control centers around the world. The 102,000-square-foot building will house mission controllers and ground support personnel providing 24-hour support for the orbiting station. The MCC next door will continue to direct Shuttle operations during Space Station assembly and utilization.

Communication

Communication with and tracking of the Shuttle are accomplished through a combination of the Tracking and Data Relay Satellite System (TDRSS, pronounced "teedruss"), which consists of three geosynchronous satellites (the first was put into orbit in 1983; the second in 1988; the third in 1989; and the fourth in 1991), one ground station at White Sands, New Mexico, and the Ground Space Flight Tracking and Data Network (GSTDN). With TDRSS supplying almost complete coverage, the GSTDN provides communication only during launch phases or as a backup to TDRSS. Commercially owned and operated domestic satellites (Domsats) link tracking stations with ground control centers. The TDRSS provides the principal coverage for all Shuttle flights. TDRSS makes it possible to monitor the flight almost continuously, increasing the probability of experiment success, reducing the need for onboard data storage, and allowing in-flight experiment changes. The MCC is supported by an emergency power building that houses generators and air-conditioning equipment for use if regular power fails. In the event a catastrophic failure shuts down the Houston control center, an emergency facility at Kennedy Space Center (KSC) is activated. The emergency control center is the Launch Control Center at KSC, incorporating just enough additional equipment to let the controllers support the flight to its conclusion.

One of the most interesting of the FCR support facilities is the display/control system, a series of projection screens on the front wall of the FCR. These displays range from plotting charts that show the spacecraft's location to actual television pictures of activities inside the Shuttle as well as views of Earth, payload deployment/retrieval, and extravehicular activity (EVA) work by mission specialists. Other displays show such things as elapsed time after launch or time remaining before a maneuver or other event. Flight controllers base many of their decisions or recommendations on the information given by the display/control system. The real-time computer complex processes telemetry and tracking data to update controllers on Shuttle systems. Controllers can call up stored reference data based on simulated flights previously conducted as practice for the actual mission. The consoles at which the flight controllers work in the FCR, the MPSR, and the POCC include one or more TV screens and the necessary switches to let the controller view data displayed on a number of different channels. The controller may view the same display being shown on the large projection screens on the front wall, or may "call up" data of special interest just by changing channels. A library of prepared reference data is available to display static information, while digital-to-television display generators provide dynamic, or constantly changing data. In the future, these traditional consoles will be augmented with engineering work stations that provide more capability to monitor and analyze data. A further update will change the way computer support is provided. Instead of driving all flight control consoles with a central main computer, each console will have its own smaller computer designed to monitor a specific system. These smaller computers then will be linked together in a network so that they can share data.

Behind the Scenes

The FCR, with its rows of consoles and large display screens, is a familiar sight to many television viewers around the world. But other equally busy areas of the MCC are just as important to the success of a flight. one such area is the Network Interface Processor (NIP) on the first floor. The NIP processes incoming digital data and distributes it on a real-time basis to the facilities associated with the FCR and support room displays. The system also handles the digital command signals to the spacecraft, the link that lets MCC do such things as keep the spacecraft guidance computer's facts and figures up to date. The Data Computation Complex (DCC), also on the first floor, processes incoming tracking and telemetry data and compares what is happening with what should be happening. often, it does not display the information unless something is going wrong. As the system evaluates factors such as spacecraft position and velocity, it also computes what maneuvers should be made to correct any shortcomings. The DCC computes and evaluates on a real-time basis. Through high-speed electronic data from the worldwide tracking station network, including TDRSS, the complex "sees" what is happening almost at the instant it happens; its computations are fast enough to aid in correcting a situation as it develops. Using this same data, the DCC also predicts where the spacecraft will be at any given time in the flight.

Further, the computers are used to give acquisition information that helps the tracking stations point their antennas at the spacecraft. And the DCC is used to monitor and evaluate telemetry information from the spacecraft to be sure that equipment is performing normally. There are five primary computers in the DCC, any of which can be used to support one FCR. Another can be used simultaneously to support a simulated flight in the other FCR for training additional teams of flight controllers. For critical mission phases, one of the computers is used as a dynamic standby, processing identical data concurrently, in case of a computer failure. The other two computers are used in developing and perfecting the computer programs used in each flight. Another important facility is the voice communications system, which enables flight controllers to talk to one another without having to leave their consoles. The system also connects controllers with specialists in support rooms, with flight crew training facilities where specific procedures can be tried on spacecraft simulators before they are recommended to the mission crew, and with the personnel along the Space Flight Tracking and Data Network. It also provides the voice link between the MCC and the spacecraft. The separately located simulation checkout and training system enables flight controllers in the MCC and flight crew in spacecraft simulators at JSC to rehearse a particular procedure or even a complete mission. The system even simulates voice and data reception from the worldwide stations of the Space Flight Tracking and Data Network.

** Information provided by NASA curator Sarah Enticknap**