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Abort Guidance System
Auxiliary Power Unit
Abort to Orbit
Russian Micropurification Unit (Russian)
Carbon Dioxide Removal System
Colony Forming Unit
Control Moment Gyroscope
Cell Performance Monitor
Compound Specific Analyzer-Combustible Products
Extravehicular Mobility Unit
Electrical Power System
Fuel Cell Monitoring System
Functional Cargo Block (Russian)
Flight Safety Office
Galley Iodine Removal Assembly
Guidance, Navigation, and Control
General Purpose Computer
Global Positioning System
Inertial Measurement Unit
International Space Station
Internal Thermal Control System
Launch Control Officer
Low Iodine Residual System
Loss of Crew
Loss of Vehicle
Minimum Duration Flight
Master Events Controller
Main Landing Gear
Micro-Meteoroid Orbital Debris
Marshall Space Flight Center
NASA Standard Initiator
Office of Safety & Mission Assurance (NASA HQ)
Protuberance Air Load
Precision Approach Path Indicator
Primary Avionics Software System
Pyrotechnic Initiator Controller
Partial Pressure of CO2
Reaction Control System/Subsystem
Remote Manipulator System
Russia or Russian
Return to Launch Site
Safety & Mission Assurance
Solid Fuel Oxygen Generator
Solid Rocket Booster
Condensate Water Processor Unit (Russian)
Space Shuttle Main Engine
Space Shuttle Program
Thermal Protection System
Loss of Crew
Crew Injury/Illness and/or Loss of Vehicle or Mission
Mercury MA-6 2/20/1962
Mercury MA-7 5/24/1962
Voskhod 2 3/19/1965
Gemini 4 6/7/1965
Skylab 4 2/8/1974
Soyuz TM-5 9/6/1988
Mercury MA-7 5/24/1962
Mir, 10/94, Crew: 6
STS-40, 6/91, Crew: 7*
STS-35, 12/90, Crew: 7*
STS-28, 8/89, Crew: 5*
STS-6, 4/83, Crew: 4*
Salyut 7, 9/82, Crew: 3
Salyut 6, 1979, Crew: 3
Salyut 1, 6/71, Crew: 3
*toxic byproducts released
ISS, 10/10/08, Crew: 3
ISS, 9/18/06, Crew: 3*
ISS, 3/05, Crew: 2
Soyuz 15 8/28/1974
Soyuz 10 4/23/1971
Skylab 2 5/26/1973
Soyuz T-8 4/22/1983
Mercury MA-9 5/16/1963
Gemini 8 3/16-3/17/1966
Soyuz 1 4/23/1967
Soyuz 21 8/24/1976
Soyuz 23 10/16/1976
Soyuz TMA-18 (22S) 9/23/2010
Soyuz T-10-1(T-10a) 9/26/1983
Apollo 12 11/14/1969
Soyuz 18-1(18a) 4/5/1975
Mercury MA-6 | 2/20/1962 | Crew: 1
False landing-bag indicator light led to entry with retropack in place as a precaution.
On February 20, 1962 a sensor indicated the heatshield was in an unlatched condition while still in orbit. If the sensor's reading were true, the heatshield could have been lost during entry, resulting in the loss of the vehicle and crew. Because the indictor said the heatshield had been dropped to the landing position, entry procedures were changed to eliminate the jettisoning of the retropack. The retropack was used as a redundant heatshield hold-down device to keep the heatshield in place. The straps holding the retropack burned through during entry, but it was thought that the aerodynamic pressure would hold the heatshield in place. After landing it was discovered that the indicator was incorrect and that the heatshield had not been dropped to the landing position.
Mercury MA-7 | 5/24/1962 | Crew: 1
Pitch horizon scanner failed, resulting in manual entry and off-target landing. Delayed crew recovery.
On May 24, 1962 the failure of the spacecraft pitch horizon scanner required the pilot to assume manual control of the spacecraft for retrofire. As a result, the spacecraft attitude was outside of the recommended range for automatic initiation of the retrofire signal. Manual initiation of the retrofire signal occurred several seconds later than scheduled.
The delay in retrofire initiation and the less-than-ideal spacecraft attitude contributed to the spacecraft landing 250 nautical miles downrange of the intended landing point which delayed crew recovery.
Voskhod 2 | 3/19/1965 | Crew: 2
Automatic descent system malfunctioned. Issues with manual entry resulted in off-target, rough terrain landing. Delayed crew recovery.
On March 19, 1965 a malfunction of the automatic descent system resulted in the use of a backup manual system for entry and landing. Difficulties encountered during manual operation and delayed retrofiring resulted in the spacecraft landing more than 1,000 km downrange from the intended landing point. The wooded, mountainous terrain caused a delay in crew recovery. (Actual distance of overshoot varies in the source documents, but most sources indicate a distance between 1,000 km and 2,500 km.)
Gemini 4 | 6/7/1965 | Crew: 2
Erroneous entry data uplinked; crew manually corrected entry flight profile.
On June 7, 1965 the computer could not be updated for entry, could not be turned off, and then stopped working entirely. The crew resorted to a rolling Mercury-type entry, rather than the lifting bank angle the computer was supposed to help them achieve.
Skylab 4 | 2/8/1974 | Crew: 3
Incorrect circuit breakers opened, resulting in the loss of the automatic control.
On February 8, 1974 while preparing foar entry, the crew inadvertently opened the stabilization and control system (SCS) pitch and yaw circuit breakers instead of the service propulsion system pitch and yaw circuit breakers. The vehicle was in an apex forward configuration for service module jettison. The commander attempted to orient the vehicle to the proper heat shield forward attitude for entry. The control commands produced no effect due to the SCS being inadvertently unpowered, and the vehicle failed to change attitude. The crew switched to “manual reaction control system direct” and oriented the vehicle to the proper attitude. The circuit breakers being in close proximity and similarly labeled, increased the potential for human error.
The failure to orient the heat shield forward would have caused loss of crew.
Soyuz TM-5 | 9/6/1988 | Crew: 2
Two de-orbit attempts failed. Crew confined to DM due to OM being jettisoned prior to 1st de-orbit attempt. Crew prevented erroneous firing of SM separation pyrotechnics.
Two de-orbit burn attempts failed and nearly led to the loss of the crew. The crew was confined to the descent module due to the orbital module being jettisoned prior to the first deorbit attempt. The first deorbit burn was prevented by a sensor glitch which disappeared after seven minutes, and then the burn started. However, the crew manually shut down the burn after three seconds.
A second burn two revolutions later occurred on time for six seconds, then stopped, and the crew manually restarted the burn. However, after an additional 60 seconds it was cut off by the autopilot. The crew manually interrupted the command sequence shortly before the descent/equipment module separation pyros were to have been fired, preventing an erroneous firing. The main cause of the crew's problems was acknowledged to be a combination of incorrect actions of the crew commander and mission control personnel.
Mercury MA-7 | 5/24/1962 | Crew: 1
RCS depletion at 80,000 ft.
This incident on May 24, 1962 involved the use of double authority control and the accidental actuation of the fly-by-wire high thrust units during certain maneuvers. The manual-system fuel was depleted near the end of the retrofire maneuver, and the automatic-system fuel was depleted at about 80,000 and 70,000 feet. Because of the early depletion of automatic-system fuel, attitude control during re-entry was not available for the required duration. Attitude rates built up after the Automatic Stabilization Control System became inoperative because of the lack of fuel, and these rates were not sufficiently damped by aerodynamic forces. The pilot chose to deploy the drogue parachute manually at an altitude of approximately 25,000 feet to stabilize the spacecraft.
To avoid the same situation on later flights, Mercury MA-8 and subsequent spacecraft contained a switch which allowed the pilot to disable and reactivate the high-thrust units at his discretion. An automatic override reactivated these thrusters just prior to retrofire. Additionally, a revision of fuel management and control training procedures was instituted for subsequent missions
Related or Recurring event
In addition to the three overheating/fire events on the ISS and the two significant events on Mir in 1997 and 1998, other overheating/fire events also occurred on:
Mir (October 1994) (A)
STS-40 (June 1991) (B)
STS-35 (December 1990) (C)
STS-28 (August 1989) (D)
STS-6 (April 1983) (E)
Salyut 7 (September 1982) (F)
Salyut 6 (1979) (G)
Salyut 1 (June 1971) (H)
Information on these events is contained in the reports below.
Related or Recurring event
On February 24, 1997 after replacing the Solid Fuel Oxygen Generator (SFOG) cartridge a fire ignited onboard the Mir space station. After becoming aware of the fire, the crew donned oxygen mask and gathered fire extinguishers. The flames blocked the emergency path to one of the docked Soyuz capsules preventing half of the 6 member crew from evacuating if the need arose. The foam fire extinguishers eventually doused the flames before an evacuation of the station was needed. The proximate cause of the fire is thought to be a piece of latex glove that contaminated the Lithium Perchlorate canister during ground operations.
Related or Recurring event
On February 26, 1998 the Russian Micropurification Unit [BMP] onboard the Russian Mir space station overheated and caused the level of carbon dioxide to climb to health-threatening levels.
Related or Recurring event
On October 10, 2008 the crew reported smoke and odor emitting from the Russian condensate water processor unit [SRV-K]. The equipment housing was hot. When the air quality was tested using the Compound Specific Analyzer-Combustible Products (CSA-CP), carbon dioxide was found at five parts per million and acid gases, hydrogen chloride and hydrogen cyanide, were zero. The [SRV-K] was powered off and replaced, which resolved the issue.
On September 18, 2006 the crew reported smoke and a solvent smell. The Elektron was found to have released toxic byproducts. The CSA-CP registered carbon dioxide at seven parts per million and hydrogen chloride and hydrogen cyanide above one part per million.
In March 2005 an electrical odor was traced to a lamp on the Service Module.
Soyuz 15 | 8/28/1974 | Crew: 2 | Related or Recurring event | Loss of Mission
Failed to dock with Salyut 3 due to Igla system malfunction.
The Soyuz 15 mission launched on August 26, 1974. Its primary mission was to dock to the Saylut 3 military space station to conduct the second phase of crewed operations aboard the Salyut 3 space station. However, docking to the Salyut 3 space station was unsuccessful due to the failure of the Igla rendezvous system and the inability to complete docking in manual mode. Due to this inability to dock, as well as spacecraft battery power limitations, the Soyuz crew was forced to abandon the mission and return to Earth within two days of launch. Gyroscope problems nearly prevented orientation of the spacecraft for the de-orbit burn. After landing, the crew was recovered on August 28, 1974.
The state commission found that the Soyuz Igla docking system needed serious modifications which could not be completed before the Salyut 3 space station decayed beyond a useable orbit. Therefore, the planned Soyuz 16 spacecraft became unnecessary to the program. (It was later flown as Soyuz 20 to a civilian Salyut station, even though it exceeded its two-year rated storage life.)
Soyuz 10 | 4/23/1971 | Crew: 3 | Related or Recurring event | Loss of Mission
Automatic docking system failed. Manual docking with Salyut not achieved.
On April 23, 1971 during automatic approach to Salyut, the Soyuz began to oscillate. The crew went to manual control and was able to complete mechanical capture. During retraction of the probe, the engines began firing because the Soyuz control system was still active. This caused damage to the docking mechanism, which stopped the probe retraction and prevented the Soyuz from completing docking to the Salyut. The crew was instructed to reconfigure cables which allowed them to send a command to release the probe's capture latches. Soyuz was released, and landing occurred on April 25.
Skylab 2 | 5/26/1973 | Crew: 3 | Related or Recurring event
Multiple failed automatic docking attempts resulted in manual docking to Skylab.
On May 26, 1973 numerous failed docking attempts resulted in the use of contingency in-flight procedures to bypass the automated docking system. Successful docking to the Skylab station ultimately relied on manual control and crew piloting skills.
The contingency procedure required the Skylab 2 crew members to don pressure suits, depressurize the command module cabin, open the tunnel hatch, cut wires in the probe, and connect the emergency probe-retract cable using a utility power outlet. The crew members were able to fire the probe-retract pyrotechnic and complete docking manually.
The failure to dock would have resulted in the loss of Skylab due to the inability to perform critical repairs.
Soyuz T-8 | 4/22/1983 | Crew: 3 | Related or Recurring event | Loss of Mission
Loss of rendezvous antenna prevented docking.
On April 20, 1983 the loss of rendezvous antenna prevented docking.
The Soyuz rendezvous radar antenna failed to deploy properly before docking attempts with Salyut 7. Several attitude control maneuvers at high rates were attempted but failed to swing the boom out. A rendezvous using only an optical sight and ground radar inputs for guidance was attempted, but was aborted when it was thought the vehicles were closing too fast. No further attempts were made to dock with the station.
The post-flight inquiry later discovered that the antenna was torn off when the Soyuz payload shroud separated.
Mir | 8/30/1994 | Crew: Soyuz 2, Mir 3 | Related or Recurring event
Soyuz TM-17 collided twice with Mir during undocking.
On January 14, 1994 during the post-separation inspection fly-around of Mir, the crew lost manual translation control due to a configuration error. The loss of control led to the Soyuz colliding with Mir several times. The cause of the collision was traced to the hand controller in the orbital module which governed braking and acceleration being switched on, disabling the equivalent hand controller in the descent module.
Mir | 8/30/1994 | Mir Crew: 2 | Related or Recurring event
Progress M-24 collided with Mir during second docking attempt.
On August 30, 1994 during the second attempt of the Progress M-24 to dock with Mir, the Progress collided with Mir's forward docking unit two to four times, and then drifted away from the station. The docking problems with Progress M-24 have been variously attributed to software or Kurs electronics failures on Progress M-24, or the failure of control equipment in the Moscow Mission Control Center.
Mercury MA-9 | 5/16/1963 | Crew: 1 | Manual Entry
Electrical faults caused loss of some systems and need to perform manual entry. Also experienced high PPCO2 levels in suit during entry operations.
During the May 16, 1963 flight electrical faults caused the loss of some systems and the need to perform manual entry. The alternating current power supply for the control system failed to operate, and it was determined that the pilot would have to make a manual retrofire and re-entry. He performed these maneuvers with close precision and landed a short distance from the prime recovery ship in the Pacific Ocean.
The malfunction during re-entry on MA-9 was traced to two connectors in an electrical amplifier.
Gemini 8 | 3/16-3/17/1966 | Crew: 2 | Emergency De-orbit | Loss of Mission
Stuck thruster caused loss of control and led to 1st U.S. emergency
During the Gemini 8 flight from March 16 – 17, 1966 a stuck thruster, number 8, which controls roll, caused a loss of control and rapid spin rate of the capsule that could have led to the crew losing consciousness. To counter the effects the stuck thruster was turned off and the re-entry control system had to be used to stabilize the capsule. Use of the re-entry control system led the Gemini safety group to declare an end to the mission, which led to the first United States emergency de-orbit. The thruster apparently short circuited while attached to the Agena target vehicle.
Soyuz 1 | 4/23/1967 | Crew: 1 | Loss of Mission
Failures in attitude control and electrical power systems resulted in a loss of mission. The launch of the intended docking target, Soyuz 2, was scrubbed.
After achieving orbital insertion on April 23, 1967 the left solar array of the Soyuz 1 spacecraft did not deploy, causing the spacecraft to receive only half of the planned solar power. Despite the solar array failure, the crew member attempted to maneuver the spacecraft. The attempt was unsuccessful because of interference between the reaction control system exhaust and the ion flow sensors.
The failure of the solar array to deploy also prevented the cover of the sun and star sensor from opening, preventing attitude control for crucial maneuvers such as spin stabilization and engine firings. The failures on Soyuz 1 prevented the launch of Soyuz 2, which had been scheduled to rendezvous and dock with Soyuz 1, causing the Soyuz 1 mission to be ended early.
Due to the failures with the control systems, the cosmonaut had to manually control the spacecraft for the critical de-orbit burn and entry while also managing the power supply of the crippled vehicle. (See also Soyuz 1 entry event)
Soyuz 21 | 8/24/1976 | Crew: 2
Separation from Salyut failed; ground command succeeded in opening latches.
On August 24, 1976 separation from Salyut failed. Prior to the latches being fully open, the latches gave a false ‘open' indication, leading to the premature firing of the Soyuz separation thrusters and jamming the latches partially open. The Soyuz remained loosely attached to the station until ground control was able to send commands to the latches, forcing them open.
Soyuz 23 | 10/16/1976 | Crew: 2 | Loss of Mission
Mission Abort due to docking failure.
The Soyuz 23 mission launched on October 14, 1976. Its primary mission was to dock to the Saylut 5 space station to conduct crewed operations aboard the station. However, docking to the Salyut 5 space station was unsuccessful due to the failure of the automated rendezvous system. Sensors used by the automatic system indicated an incorrect lateral velocity, causing unnecessary firing of the thrusters during rendezvous. The automatic system was turned off, but no fuel reserves remained for a manual docking attempt with the Salyut 5. The mission was aborted, and low spacecraft battery reserves forced the crew to return early. Upon re-entry/landing the capsule landed in a lake during a snow storm, delaying crew recovery (see Soyuz 23 landing event). The crew was recovered on October 16, 1976.
Soyuz TMA-18 (22S) | 9/23/2010 | Crew: Soyuz 3, ISS 3
First attempt to separate from ISS failed; ISS crew succeeded in bypassing faulty sensor.
The first attempt to separate the Soyuz from ISS on September 23, 2010 failed. A hatch sensor on the Poisk docking port of the Zvezda module prevented hooks on the Poisk side from opening.
SpaceShipOne 16P | 9/29/2004 | Crew: 1
Uncommanded vehicle roll. Control regained prior to apogee.
On September 29, 2004 SpaceShipOne performed a series of 60 rolls during last stage of engine burn. SpaceShipOne coasted to 103 km of altitude and successfully completed the first of two X-Prize flights. The motor was shut down when the pilot noted that his altitude predictor exceeded the required 100 km mark. During the motor burn the spacecraft began to roll uncontrollably, but the pilot continued despite advice from the ground to shut the motor down and abort the attempt.
The thin air at that altitude meant that the control surfaces didn't have enough air flowing over them, so they lost effectiveness to compensate for the roll as the spacecraft pointed nearly straight up. The pilot needed to correct the rolling that occurred because of asymmetric thrust coming from the engine.
To correct the issue for the 17P flight, the amount of allowable “down pitch trim” was limited, to avoid the negative-lift condition. The solution was to more gently turn the corner, such that a forward correction later would not be needed. Pointing straight up at burnout was determined to be acceptable, as long as negative lift was not created. This problem was corrected on SpaceShipTwo.
Apollo 14 | 1/31/1971 | Crew: 3
Multiple failed docking attempts. Contingency procedures developed to mitigate risk of recurring docking anomaly. Docking successful.
On January 31, 1971 six docking attempts were unsuccessful following translunar injection. On the seventh try the command module pilot was told to fire thrusters to hold the command module to the lunar module while the docking probe was retracted. The docking capture latches were triggered to fire the probe-retract pyrotechnic, and docking was successful. After docking, the drogue and probe were examined by the crew and appeared normal. No other issues arose with the docking mechanisms.
The most likely cause of the docking issue was a piece of debris or ice on the docking probe from rain water entering the boost shroud the day before launch. The mission would have been No-Go for lunar module separation and landing if a backup procedure for docking and retracting the docking probe in an emergency had not been developed.
Soyuz T-10-1 (T-10a) | 9/26/1983 | Crew: 2 | Loss of Vehicle/Mission | Related or Recurring event
Pad booster fire/explosion. Capsule Escape System used.
Shortly before liftoff on September 26, 1983 fuel spilled around the base of the Soyuz launch vehicle and ignited the vehicle. Launch control activated the escape system, but the control cables were burnt.
Twenty seconds later ground control activated the escape system by radio command. By this time the booster was engulfed in flames.
Explosive bolts fired to separate the descent module from the service module. Explosive bolts also fired to separate of the upper shroud from the lower shroud. The escape system motor pulled the orbit module and descent module, still encased within the upper shroud, away from the booster at 14 to 17g of acceleration.
Seconds after the escape system activated, the booster exploded, destroying the launch complex.
The descent module separated from the orbital module and dropped free from the shroud. The descent module heat shield was discarded to expose the solid-fueled landing rockets. A fast-opening emergency parachute was deployed and landing occurred about four km from the launch pad.
Apollo 12 | 11/14/1969 | Crew: 3
Lightning strike on ascent.
During the Apollo 12 launch on November 14, 1969 lightning struck the spacecraft.
Light rain was falling, but weather conditions did not indicate any thunderstorm activity. There were seven miles of visibility with cloud break estimated at 800 feet and overcast conditions at 10,000 feet.
At 11:22am, T+36 seconds, the crew saw a bright light.
At T+36.5 seconds many errors occurred: Fuel Cells 1, 2, and 3 disconnected; Main Buses A and B were under-voltage; Alternating Current (AC) Buses 1 and 2 overloaded. The warning lights and alarm came on in the cabin, indicating failure of the Inertial Stabilization System.
At T+52 seconds (13,000 feet) lightning struck the vehicle and the Inertial Measurement Unit platform tumbled.
The potential effect on the vehicle was induction into wiring, depending on the location and rate of change of potential and direct current flow in grounding. The high negative voltage spike (delta voltage/delta time) caused the Silicon Controlled Rectifiers to trip on the Fuel Cell and AC Inverter overload sensors. Failures occurred in four Service Module Reaction Control System helium tank quantity measurements, five thermocouples, and four pressure/temperature transducers.
Using power from the Battery Relay Bus, the crew reconnected the Fuel Cells to Main Bus A and B, and reconnected the inverters to AC Bus 1 and 2. The mission continued.
Soyuz 18-1(18a) | 4/5/1975 | Crew: 2 | Loss of Vehicle/Mission
Electrical fault caused premature firing of half of the 2nd stage separation bolts, resulting in the inability to fire the remaining ones. Staging failure resulted in abort sequence being used at T=295 seconds.
During ascent on April 5, 1975 an electrical malfunction in the Soyuz booster prematurely fired two of the four explosive latches holding the core of the first and second stage together. This severed the electrical connections necessary for firing the remaining two latches. When the core first stage burned out, it could not be cast off as designed.
Ignition of the second stage occurred normally, but the booster was rapidly dragged off course by the weight of the depleted core first stage. When the course deviation reached 10 degrees, the automatic safety system activated, shutting down the booster and separating the Soyuz capsule from the launch vehicle. At the time of separation, the Soyuz was 180 km high and traveling at 5.5 km per second.
The crew endured a 20+ g re-entry and landed in the Altai Mountains. The capsule rolled down a mountain side, and was caught in bushes just short of a precipice. After an hour of waiting in the cold next to the capsule, the crew was discovered by locals speaking Russian.
One crew member suffered internal injuries from the high-g re-entry and downhill fall and never flew again.
On-pad Abort Events (1984-93)
Related or Recurring event
Mir Collision Events (1994-1997)
LANDING & POSTLANDING