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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
Soyuz TMA-10 (14S)
Soyuz TMA-11 (15S) 4/19/2008
Soyuz 11 6/30/1971
Soyuz 18-1(18a) 4/5/1975
Vostok 1 | 4/12/1961 | Crew: 1 | Related or Recurring event
On April 12, 1961 ten seconds after retrofire, commands were sent to separate the Vostok service module from the re-entry module. The Vostok equipment module unexpectedly remained attached to the re-entry module by a bundle of wires. The two halves of the spacecraft began entry and experienced strong gyrations as Vostok 1 crossed over Egypt. At this point in the entry profile the wires connecting the modules broke, causing the two modules to separate. After the separation of the two modules, the descent module settled into the proper entry attitude and landed as intended.
Vostok 2 | 8/7/1961 | Crew: 1 | Related or Recurring event
On August 7, 1961 during entry it was discovered that lights on the control console in the cabin, which were powered from the instrument module, remained on. Because the lights were on, it was thought that separation of the two modules had not happened. However, the separation between the capsule and the instrument compartment had taken place. A multi-cable umbilical line between two compartments apparently failed to cut off. This likely explains why the crew member heard the separation jolt, but did not see the control lights go out. The electric current was still flowing to the control panel via umbilical cables. The two modules eventually separated when the cable burned through during entry.
Vostok 5 | 6/19/1963 | Crew: 1 | Related or Recurring event
On June 19, 1963 the Vostok service module failed to separate cleanly from the re-entry sphere resulting in wild gyrations until the heat of re-entry burned through the non-separating retraining strap.
Voskhod 2 | 3/19/1965 | Crew: 1 | Related or Recurring event
On March 19, 1965 a communication cable connecting the landing module with the orbital module failed to separate at the appropriate time, causing the two modules' common center of gravity to shift, causing the two modules to begin spinning around it. The spinning eventually stopped at an altitude of about 100 kilometers, when the connecting cable burned through and the landing module slipped free.
Soyuz 5 | 1/18/1969 | Crew: 2 | Related or Recurring event
During entry procedures on January 18, 1969 the connecting latches between the Descent Module (DM) and the Service Module (SM) of the Soyuz spacecraft failed to separate at the intended time as designed. The failure to separate led the Soyuz to undergo a “nose first” entry. During the entry, layers of the descent module shell peeled away due to heating and internal pressure. As a result of the heating, the connections between the DM and SM were broken and allowed the DM to return to the normal orientation. The DM survived the unplanned heating in the unshielded areas of the capsule.
Soyuz TMA-10 (14S) | 10/21/2007 | Crew: 3 | Related or Recurring event
During Soyuz TMA-10 entry on October 21, 2007, the Soyuz instrumentation and propulsion module (IPM) failed to properly separate from the descent module (DM). This resulted in a ballistic entry. The abnormal entry attitude(hatch-forward) during early descent caused excessive heating on the hatch and back shell of the descent module.
Soyuz TMA-11 (15S) | 4/19/2008 | Crew: 3 | Crew Injury (1) | Related or Recurring event
Ballistic, high g entry and landing over 400 km short of intended target.
During Soyuz TMA-11 entry on April 19, 2008, the Soyuz instrumentation and propulsion module (IPM) failed to properly separate from the descent module (DM). This resulted in a ballistic entry, higher g loads during descent, and the spacecraft landing more than 400 km short of the intended target. The abnormal entry attitude(hatch-forward) during early descent caused excessive heating on the hatch and back shell of the descent module. The recovery team's arrival at the landing site was delayed by approximately 45 minutes due to the off-target landing. One crew member was later hospitalized because of injuries sustained during entry and landing.
A Russian investigation into the cause of the DM/IPM separation system failure concluded that one of the five pyrotechnically actuated locks, which attach the Soyuz instrumentation and propulsion module to the descent module, failed to release at the proper time.
Mercury MR-4 | 7/21/1969 | Crew: 1 | Loss of Capsule
Inadvertent hatch pyrotechnic firing. Capsule sunk. Astronaut nearly drowned.
After landing on July 21, 1961 the spacecraft hatch pyrotechnic charges prematurely fired. The crew member was able to escape from the emergency situation, but because of waves flooding the capsule, the capsule sunk. The crew member was nearly drowned when the flight suit took on water from an unsealed neckdam. The crew member was rescued after three to four minutes in the water.
Soyuz 11 | 6/30/1971 | Crew: 3 | Loss of Crew
Pyrotechnic system failure resulted in crew module rapid depress.
On June 30, 1971 during separation of the orbital and service modules from the descent module, the pyrotechnic system did not operate as intended. All of the pyrotechnics fired simultaneously rather than the designed sequential firing mode. This caused a pressure equalization seal to open in the descent module at a higher-than-designed altitude, resulting in the rapid depressurization of the crew module. The rapid depress led to loss of consciousness of the crew.
All three crew members were lost.
STS-51 | 9/12/1993 | Crew: 5 |
Both port-side primary and secondary SUPER*ZIP explosive cords fired, resulting in containment tube failure and damage in the payload bay.
On September 12, 1993 the STS-51 mission commands intended to initiate the primary SUPER*ZIP explosive cord resulted in the simultaneous firing of both the primary explosive cord and back-up explosive cord. This simultaneous explosive cord firing resulted in the rupture of a SUPER*ZIP containment tube and release of contaminants and high-energy debris into the orbiter cargo bay. The orbiter sustained damage to blankets, wire tray covers, the 1307 bulkhead, and Thermal Protection System tiles. If debris had hit critical items it could have resulted in a loss of the orbiter and crew.
STS-114 | 5/26/2006 | Crew: 7
Bird strike on External Tank.
Loss of foam from External Tank PAL ramp.
TPS gap filers protruding. Removed during third mission EVA.
Missing O-ring resulted in ejection of one of two NSIs, compromising the ET forward
separation bolt function and damaging secondary structure and a thermal blanket.
STS-114 encountered four close-call events.
STS-112 | 10/7/2002 | Crew: 6
T-0 umbilical issues resulted in none of the system A pyrotechnic charges firing.
The post-launch data review of the October 7, 2002 launch determined that none of the system A pyrotechnics (NASA Standard Initiators) for the Solid Rocket Booster hold-down posts nor the External Tank Vent Arm System discharged.
The Master Events Controller (MEC) provided the signal to the Pyrotechnic Initiator Controller (PIC) to discharge the pyrotechnics. Therefore the MEC common wiring, as well as the wiring between the MEC in the orbiter and the PIC rack on the ground, were suspected of not working properly.
All connectors and electrical circuits were inspected and tested, but no root cause was identified to explain the anomaly.
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.
Crew Injury/Illness and/or Loss of Vehicle or Mission
Related or Recurring event
Service/Descent Module (1961-2008)
LANDING & POSTLANDING