Editing Human spaceflight (section)

=== Fatality risk ===
{{Further|List of spaceflight-related accidents and incidents}}

{{As of|2015|December}}, 23 crew members have died in accidents aboard spacecraft. Over 100 others have died in accidents during activities directly related to spaceflight or testing.

{| class="wikitable"
|-
!Date
!Mission
!Accident cause
!Deaths
!Cause of death
|-
| 27 January 1967
| [[Apollo 1]]
| Electrical fire in the cabin, spread quickly by {{convert|16.7|psi|bar|abbr=on}} pure oxygen atmosphere and flammable nylon materials in cabin and space suits, during pre-launch test; inability to remove [[plug door]] hatch cover due to internal pressure; rupture of cabin wall allowed outside air to enter, causing heavy smoke and soot
| style="text-align: center;" | 3
| [[Cardiac arrest]] from [[carbon monoxide]] poisoning
|-
| 24 April 1967
| [[Soyuz 1]]
| Malfunction of primary landing parachute, and entanglement of reserve parachute; loss of 50% electrical power and spacecraft control problems necessitating emergency abort
| style="text-align: center;"| 1
| [[Physical trauma|Trauma]] from crash landing
|-
| 15 November 1967
| [[X-15 Flight 3-65-97]]
| The accident board found that the cockpit instrumentation had been functioning properly, and concluded that pilot [[Michael J. Adams]] had lost control of the X-15 as a result of a combination of distraction, misinterpretation of his instrumentation display, and possible [[Vertigo (medical)|vertigo]]. The electrical disturbance early in the flight degraded the overall effectiveness of the aircraft's control system and further added to pilot workload.
| style="text-align: center;"| 1
| Vehicle breakup
|-
| 30 June 1971
| [[Soyuz 11]]
| Loss of cabin pressurization due to valve opening upon Orbital Module separation before re-entry
| style="text-align: center;"| 3
| [[Asphyxia]]
|-
| 28 January 1986
| [[STS-51L]] [[Space Shuttle Challenger disaster|Space Shuttle ''Challenger'']]
| Failure of [[O-ring]] inter-segment seal in one [[Space Shuttle Solid Rocket Booster|Solid Rocket Booster]] in extreme cold launch temperature, allowing hot gases to penetrate casing and burn through a strut connecting booster to the [[Space Shuttle external tank|External Tank]]; tank failure; rapid combustion of fuel; orbiter breakup from abnormal aerodynamic forces
| style="text-align: center;"| 7
| Asphyxia from cabin breach, or trauma from water impact<ref>{{cite web|url=https://history.nasa.gov/kerwin.html |title=Report from Joseph P. Kerwin, biomedical specialist from the Johnson Space Center in Houston, Texas, relating to the deaths of the astronauts in the Challenger accident |work=NASA |url-status=dead |archive-url=https://web.archive.org/web/20130103015825/https://history.nasa.gov/kerwin.html |archive-date=3 January 2013 }}</ref>
|-
| 1 February 2003
| [[STS-107]] [[Space Shuttle Columbia disaster|Space Shuttle ''Columbia'']]
| Damaged [[reinforced carbon-carbon]] heat shield panel on wing's leading edge, caused by a piece of [[Space Shuttle external tank|External Tank]] foam insulation broken off during launch; penetration of hot atmospheric gases during re-entry, leading to structural failure of the wing, loss of control and disintegration of the orbiter
| style="text-align: center;"| 7
| Asphyxia from cabin breach, trauma from dynamic load environment as orbiter broke up<ref>{{cite web |title=Columbia Crew Survival Investigation Report |url=http://www.nasa.gov/pdf/298870main_SP-2008-565.pdf |website=NASA.gov |publisher=NASA}}</ref>
|-
| 31 October 2014
| [[SpaceShipTwo]] [[VSS Enterprise crash|VSS ''Enterprise'' powered drop-test]]
| Copilot error: premature deployment of "[[Feathering (reentry)|feathering]]" descent air-braking system caused the disintegration of the vehicle in flight; pilot survived, copilot died
| style="text-align: center;"| 1
| [[Physical trauma|Trauma]] from crash
|}