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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
SRB Seal Events (1981-96)
Other significant STS TPS anomalies:
STS-6, 41B, 51G, 27*, 28, 40, 42, 45
*Most severe tile damage to date.
Apollo 15 8/7/1971
O2 Fire - Soviet
ISS, Increment 5&6 mid 2002-2/03
Apollo 1 (AS-204) 1/27/1967
Other SRB gas seal anomalies:
STS-2, 6, 41B, 41C, 41D, 51C, 51D, 51B, 51G, 51F, 51I, 51J, 61A, 61B, 61C, 42, 70, 71, 78
Related or Recurring event
Other Thermal Protection System Damage Events
In addition to the Thermal Protection System (TPS) damage on STS-1, STS-51D, and STS-107, the following Space Shuttle flights experienced TPS damage:
STS-6 (April 1983)
STS-41B (February 1984)
STS-51G (June 1985)
STS-27 (December 1988)
STS-28 (August 1989)
STS-40 (June 1991)
STS-42 (January 1992)
STS-45 (March 1992)
Additional information can be found in the reports linked below.
STS-6 Mission Report STS-41B MER Report STS-41B Mission Report STS-51G MER Report STS-51G Mission Report STS-27 MER Report STS-27 Mission Report STS-27 Close Call STS-28 Mission Safety Eval Record STS-28 MER Report STS-28 Mission Report STS-40 Debris, Ice, TPS Assessment STS-40 Mission Safety Evaluation STS-40 Mission Report STS-42 Debris, Ice, TPS Assessment STS-42 Mission Report
Apollo 15 | 8/7/1971 | Crew: 3
Landed with only 2 of 3 parachutes.
On August 7, 1971 the Apollo capsule, Endeavour, dropped into the Pacific Ocean about 320 miles (515 kilometers) north of Hawaii. During the Earth landing phase, after the main parachutes were deployed and shortly after Reaction Control System (RCS) propellant dumping, one of the main parachutes was observed to be deflated when exiting the clouds (3 of 6 fabric risers failed and two-thirds of the suspension lines were missing). One of the main parachutes was recovered after landing, but the failed parachute was not recovered.
The investigation was divided into three areas which were likely causes of the parachute failure.
The forward heat shield was suspected because of the close proximity to the spacecraft flight path during the period when the failure occurred.
A broken riser/suspension-line connector link was found on the recovered parachute, indicating the possibility of broken links in the failed chute.
The Command Module RCS propellant depletion firing had just been completed, and fuel (monomethyl hydrazine) expulsion was in progress at the time of the failure, indicating the possibility of damage from propellants.
Analysis and testing ruled out possible causes one and two, but a test of raw fuel expulsion after RCS firing produced burning outside of the engine. The flame front extended up to eight feet from the engine exit and unburned fuel was sprayed up to 10 feet from the engine and ignited by burning droplets. This was considered the most likely cause of the parachute failure.
STS-51D | 4/19/1985 | Crew: 7
Right brake failed (locked up) causing blowout of inboard tire and significant damage to outboard tire.
On April 19, 1985 the right brake on the orbiter failed, causing the blowout of an inboard tire and significant damage to an outboard tire. A crosswind of about 8 knots, gusting up to 12, resulted in extra brake energy on the right brake while returning to and holding the runway centerline during rollout. The number 3 stator on both the inboard and outboard right main landing gear (MLG) brakes broke into several pieces, causing both brakes to lock during rollout. The inboard right brake locked at 20.6 knots and 113 feet, before the orbiter stopped and the outboard right brake locked for the last 5 feet of rollout. The right MLG inboard tire burst 33 feet after the inboard brake locked. Eleven of 16 cord layers were worn through before the tire burst. The right MLG brakes failed and locked due to thermal soak-back when the number 3 stators broke.
The corrective action includes the following standard procedures to prevent heat soak-back:
1. Brake-on velocity between 140 and 120 knots.
2. Deceleration rate between 8 and 10 ft/sec2.
3. Deceleration rate reduced to 6 ft/sec2 at 40 knots. If brake-on velocity exceeds 140 knots, continue 8 to 10 ft/sec2 deceleration.
Navy Chamber | 11/17/1962 | Crew: 4 | Crew Injury (4)
Fire started in a 100% oxygen environment at 5 psi. Four officers injured.
On November 17, 1962 four Navy officers were injured, two seriously, when a fire started in the altitude chamber they were occupying in a 20 day experiment at the U.S. Navy Air Crew Equipment Laboratory as part of a NASA atmosphere validation program.
The chamber contained 100% oxygen at 5 psi. The fire started when one officer changed a light bulb in an energized 24 volt DC light fixture. One wire in the fixture became disconnected resulting in arcing. A cotton towel was used in an attempt to smoother the fire. The towel caught fire, and the flames spread to the officers' clothes.
Altitude Chamber O2 Fire | 3/23/1961 | Crew: 1 | Loss of Crew
Alcohol wipe hit hot plate and started fire in oxygen-rich test chamber.
On March 23, 1961 a cosmonaut in an altitude chamber was removing the sensors that had been attached to him during an experiment. He cleaned the places where the sensors had been attached with cotton wool soaked in alcohol, and without looking threw away the cotton wool. The cotton wool landed on the ring of an electric hot plate in the oxygen-charged atmosphere of the chamber. In conditions of high oxygen concentration, normally non-flammable substances can burn vigorously. The cosmonaut's training suit caught fire. Unaccustomed to the vigor of high-oxygen fires, the cosmonaut would only have spread the flames further by attempting to smother them. The doctor on duty noticed the conflagration through a porthole and rushed to the hatch, which he could not open because the internal pressure kept the inward swinging hatch sealed. Releasing the pressure through bleed valves took several minutes and the cosmonaut later died in the hospital from the burns.
ISS | 8/2001 | Crew: 3
Extremely high methanol levels in FGB air sample.
During August 2001 Functional Cargo Block [FGB] air samples contained extremely high methanol levels. The source of the methanol was never identified.
ISS, Increment 5&6 | mid 2002-2/03 | Crew: 3-10
Formaldehyde periodically exceeded long-term limits.
During ISS Increments 5 and 6, which spanned from mid-2002 until February 2003, formaldehyde levels onboard the station periodically exceeded the long-term limits.
STS-93 | 7/23/1999 | Crew: 5
At T+5 a short on AC1 Phase A resulted in loss of SSME1 Controller A and SSME3 Controller B.
SSME3 H2 leak: early LOX depletion and shutdown.
STS-93 encountered two close-call events.
Apollo I (AS-204) | 1/27/1967 | Crew: 3 | Loss of Crew
Crew cabin fire (electrical short + high pressure O2 atmosphere).
On January 27, 1967 the crew cabin of Apollo 1 caught fire during a test with three crew members inside. The cabin was filled with a pure oxygen atmosphere and pressurized greater than ambient pressure (16.7 psi). Over the course of several hours, the oxygen permeated all materials in the cabin, which had been tested to the normal flight pressure of pure oxygen (5 psi). When the fire began it spread rapidly. Due to the pressure in the cabin, the crew members could not open the hatch to escape. Technicians in the room outside the capsule attempted to open the hatch but were driven back by the heat and smoke. Some technicians donned the available gas masks, but the masks were designed to protect against hypergolic propellant fumes, not smoke. Consequently, these technicians lost consciousness after a short time in the smoke-filled room.
All three crew members were lost.
The fire was caused by an electrical short from an unprotected wire. A subsequent review of all wiring dioded to both Main Bus A and B identified a problem with an environmental control system instrumentation wire powered from Main Bus A and B. The wire was routed over plumbing lines on the crew compartment floor, located below the left-hand crew seat, going into the left-hand equipment bay, between the environmental control unit and the oxygen panel. This Teflon-insulated wire should have had a protective Teflon overwrap, but closeout photos showed that the overwrap had slipped down, no longer providing protection. The commander likely contacted this wire with his foot when he turned to change his communications cable. The most probable initiator of the fire is an electrical arc from this wire, which was unprotected from external damage.
Factors contributing to this accident include:
Other SRB Seal Events | Related or Recurring event
SRB gas sealing anomalies have also occurred on:
STS-2 November 12, 1981
STS-6 April 4, 1983
STS-11 (STS-41B) February 3,1984
STS-41C April 6,1984
STS-41D August 30, 1984
STS-51C January 24,1985
STS-51D April 12, 1985
STS-51B April 29, 1985
STS-51G June 17,1985
STS-51F July 29, 1985
STS-51I August 27, 1985
STS-51J October 3, 1985
STS-61A October 30, 1985
STS-61B November 26,1985
STS-61C January 12, 1986
STS-42 January 22, 1992
STS-71 June 27, 1995
STS-70 July 13, 1995
STS-78 June 20, 1996
Related or Recurring event
TPS Entry Events (1981-2003)
LANDING & POSTLANDING