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— CH. 1 · MISSION CONTROL ARCHITECTURE —

Flight controller

~5 min read · Ch. 1 of 5
5 sections
  • The Mission Operations Control Room, known as MOCR and pronounced moh-ker, housed the flight controllers who monitored space missions in real time. This physical space later became the Flight Control Room or FCR, pronounced ficker. Controllers sat at computer consoles where they used telemetry to track technical aspects of a mission. Each controller served as an expert in one specific area while constantly communicating with additional experts located elsewhere. These remote experts formed teams called backrooms that supported the frontroom operations. The backroom was formerly named the Staff Support Room or SSR and is now called the Multi-Purpose Support Room or MPSR, pronounced mipser. Frontroom flight controllers integrated system needs into larger vehicle requirements and worked with the rest of the team to develop cohesive plans. Information flowed from the backroom to the frontroom to Flight and then potentially to the onboard crew. A typical MOCR or FCR team consisted of more seasoned controllers than those found in the SSR or MPSR. Senior flight controllers periodically cycled back to support roles within the backroom. During the descent of the Apollo 11 Lunar Module Eagle, program alarms labeled 1202 and 1201 triggered a critical decision moment. GUIDO Steve Bales trusted guidance backroom experts like Jack Garman when determining if the computer overload could be ignored. Without this backroom support, a single console operator might make a bad call based on faulty memory. Modern International Space Station operations require full teams only during high-intensity periods such as joint Shuttle missions. Controllers accept responsibility for operations without MPSR support most of the time today.

  • Flight controllers faced life-or-death choices during high-stakes moments in space history. The Apollo 11 Lunar Module computer overloaded because astronauts forgot to switch off their upper-stage radar before activating the downward-pointing radar. Guidance officer Steve Bales had mere seconds to decide whether it was safe to land or abort the mission just feet above the Moon. Bales later accepted the NASA Group Achievement Award from President Richard Nixon on behalf of the Apollo 11 mission operations team. Lightning struck the Saturn V rocket during the launch of Apollo 12 and knocked out all telemetry plus multiple command module systems. Seconds before mission abort, EECOM controller John Aaron determined that switching to backup electrical power distribution telemetry conditioning would reveal the true nature of the issue. During Space Shuttle mission STS-51-F, a main engine failed while ascending to orbit. Indications soon followed showing a second engine beginning to fail which would have caused a mission abort. Booster officer Jenny Howard Stein decided that anomalous readings on the second engine were sensor errors rather than actual engine problems. At her direction the crew inhibited the sensor and saved both the mission and possibly the crew. These decisions required immediate action under extreme pressure where performance carried ultimate consequences for human lives. Flight Controllers' Creed stated they must always be aware that suddenly and unexpectedly they might find themselves in roles with final outcomes.

  • Flight controller responsibilities shifted significantly over time as technical systems changed and new positions emerged. The EECOM handled command and service module communication systems through Apollo 10 before being reassigned to a new position called INCO. New controllers were added regularly while tasks were reassigned to other controllers to keep pace with evolving technology. For long-duration missions there is now more than one CAPCOM assigned to different shift teams. After control of U.S. spaceflights moved to the Johnson Space Center in the early 1960s each CAPCOM used the radio call sign Houston. Shrinking size of the astronaut corps at the end of the Shuttle program meant fewer astronauts were available for CAPCOM duties. Non-astronauts from the space flight training and flight controller branches now function as CAPCOM during ISS missions. The role was filled solely by astronauts for the Apollo and Shuttle missions though astronauts still take the CAPCOM position during critical events like docking and EVA. NASA Ames Research Center conducted field trials of advanced computer support for astronaut and remote science teams to test possibilities for automating CAPCOM. The former mission operations directorate or MOD position was renamed FOD when the flight crew operations directorate merged back with MOD beginning in August 2014.

  • Flight Director leads the entire flight control team and holds overall operational responsibility for all decisions regarding safe expedient flight. This person monitors other flight controllers while remaining in constant verbal communication via intercom channels called loops. Flight Operations Directorate serves as a representative of senior management chain at JSC to help the flight director make decisions without safety-of-flight consequences. Cost or public perception consequences fall under this directorate but they cannot overrule the flight director during a mission. Spacecraft Communicator or CAPCOM generally communicates directly only with the crew of a crewed space flight. The acronym dates back to Project Mercury when the spacecraft was originally termed a capsule. NASA felt it important for all communication with astronauts to pass through a single individual in the Mission Control Center. A private communication channel can be established between astronauts and the flight surgeon to provide doctor-patient confidentiality. Public Affairs Officer provides mission commentary to supplement air-to-ground transmissions and explain flight control operations to news media and public. This role is often referred to colloquially as The Voice of Mission Control. The group serving these positions may change individuals but they will always bear the same titles and serve identical functions across every vehicle's flight control team.

  • Mission control facilities operate globally beyond NASA centers including Roscosmos, JAXA, and ESA alongside American agencies. Baikonur Cosmodrome serves as launch control center for Roscosmos in Baikonur Kazakhstan. Beijing Aerospace Command and Control Center handles missions for China National Space Administration in Beijing. Christopher C. Kraft Jr. Mission Control Center operates for NASA in Houston. John H. Chapman Space Centre manages robotics missions from Longueuil Quebec for Canadian Space Agency. European Space Operations Centre runs operations from Darmstadt Germany for European Space Agency. German Space Operations Center includes Columbus Control Centre located in Oberpfaffenhofen Germany. Guiana Space Centre acts as launch control center for European Space Agency in Kourou French Guiana. Johnson Space Center remains primary mission control center for NASA in Houston Texas. Kennedy Space Center serves as launch control center for NASA in Cape Canaveral Florida. Payload Operations and Integration Center sits at Marshall Space Flight Center in Huntsville Alabama. RKA Mission Control Center operates near Moscow Russia for Roscomos. Tanegashima Space Center functions as launch control center for JAXA on Tanegashima Island Japan. Tsukuba Space Center serves as mission control center for JAXA in Tsukuba Japan.

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Common questions

What is the role of a flight controller in space missions?

A flight controller monitors technical aspects of a mission using telemetry from computer consoles. Each controller serves as an expert in one specific area while communicating with remote experts to support frontroom operations.

Who was Steve Bales and what decision did he make during Apollo 11?

Guidance officer Steve Bales decided whether it was safe to land or abort the mission when program alarms 1202 and 1201 triggered during the descent of the Lunar Module Eagle. He trusted guidance backroom experts like Jack Garman to determine if the computer overload could be ignored.

When did control of U.S. spaceflights move to the Johnson Space Center?

Control of U.S. spaceflights moved to the Johnson Space Center in the early 1960s. After this transfer each CAPCOM used the radio call sign Houston for all communication with astronauts.

Where are global mission control facilities located outside NASA centers?

Global mission control facilities include Baikonur Cosmodrome in Kazakhstan for Roscosmos, Beijing Aerospace Command and Control Center in China, and Tsukuba Space Center in Japan for JAXA. European Space Agency operates from Darmstadt Germany and Kourou French Guiana while Canadian Space Agency manages robotics from Longueuil Quebec.

How do flight controllers handle high-stakes decisions under pressure?

Flight controllers accept responsibility for operations without support teams most of the time today and make life-or-death choices during critical moments. They must always be aware that they might suddenly find themselves in roles with final outcomes affecting human lives.