In-flight aborts and rescue options

In the context of the Orion spacecraft, in-flight aborts and rescue options are activities which might take place if there were an emergency during a mission. Like all previous U.S. manned spacecraft, an in-flight abort can occur when a major component fails (such as a malfunctioning altitude-control thruster on Gemini 8) or when a crew member becomes dangerously ill (such as that on the Soyuz T-14 flight to Salyut 7 in 1985, when the commander became seriously ill).
In most cases, NASA Mission Control in Houston will immediately abort the flight and instruct the crew to return home on the next orbit, and because the Orion crew module was designed to touch down on both land and water, NASA can direct the spacecraft to either a ground landing in California or New Mexico, or a water splashdown near major U.S. Naval forces.
The only case in which an in-flight abort occurred in which astronauts or cosmonauts could not return to Earth on a short notice was that of the flight of Apollo 13 in 1970. On that flight, an oxygen tank in the spacecraft's Service Module exploded, crippling the onboard life-support systems and forcing astronauts Jim Lovell, Fred Haise, and Jack Swigert to use the Lunar Module as a "lifeboat" until the crew, after swinging around the Moon, was just three hours away from a splashdown in the Pacific Ocean. Although the crew endured an ordeal of little water, cold temperatures, and a decaying trajectory that had to be corrected twice during the return trip, the biggest concern was the spacecraft's heat shield, which may have been cracked by the onboard explosion. If such a crack did occur, it would have resulted in a scenario similar in nature to the in 2003.
As such, NASA is currently developing both in-flight abort and rescue procedures that date back to the Apollo-Soyuz flight in 1975 and highlighted by the Columbia Accident Investigation Board (CAIB). These scenarios would allow NASA to bring a crew home within two hours on a low-Earth orbit flight and in seven days on a lunar sortie flight.
In-flight abort
Low-Earth orbit
On an in-flight abort, such as the early flights to the International Space Station, Mission Control in Houston will direct the crew to leave the ISS and use the Orion CEV for a ground landing at either Edwards Air Force Base in California or White Sands Space Harbor in New Mexico, where any injured or sick crew members can receive immediate care in a manner similar to that of a wounded combatant in either Vietnam or Iraq. Such an in-flight abort would have to occur when the Orion CEV is intact and undamaged, and the cause of the in-flight abort lies within the ISS itself or when a crew member becomes ill. For an ill crew member, the ISS can remain manned by a skeleton crew until another Orion or a private spaceflight is launched.
Lunar missions
In the event of a malfunction of lunar flight hardware that does not jeopardize the crew or spacecraft, Mission Control will abort the lunar flight and depending on the phase of the mission, would require the crew to make a lunar flyby (as done on Apollo 13), enter orbit around the Moon (as done on Apollo 8), or perform, using both LSAM and Orion SM engines, a "direct abort," in which the Orion/LSAM combination is turned around so that the LSAM's descent and ascent engines face the Moon, and in a manner similar to the RTLS abort maneuver on the Space Shuttle, firing its engines so that the spacecraft reverses course and heads straight back to Earth, using the onboard Orion engine for minor course refinements. Using the skip entry techniques first demonstrated by the former Soviet Union for their failed lunar program, the Orion CEV would then either land in California or New Mexico in a manner similar to that for a near-Earth abort.
Space rescue
Low-Earth orbit
Because of the stigma placed by the Columbia Accident Investigation Board (CAIB) to provide the needs for an in-flight rescue, all Orion spacecraft will utilize a new generation of universal docking systems first demonstrated on Apollo-Soyuz and is now a standard part of the U.S. docking system on the ISS. In the event the Orion spacecraft is damaged during launch, but is able to reach the ISS, the crew would use the ISS as a "safe haven" and an unmanned "rescue Orion," similar to that of the Skylab Rescue and rescue flights, would then be launched and if undamaged, would dock with the ISS. At that time, the crew would have jettison the damaged Orion CEV with Mission Control deorbiting the spacecraft to a crash landing in the Pacific Ocean away from known shipping lanes in a manner used for the unmanned Progress cargo ships used by the Russian space program.
In the event the damage to the Orion spacecraft is severe enough to prevent docking with the ISS, or fails to reach the ISS at all, NASA would then rush an unmanned Orion/Ares I stack and launch it in a manner similar to that "Launch on Need" rescue that was planned, but never carried out for the STS-125 flight to the Hubble Space Telescope. Once the "rescue Orion" reaches the damaged Orion spacecraft, a physical docking would take place, allowing a crew transfer without the need to perform an EVA like those required for Shuttle-to-Shuttle rescues. In the event of a failed capture, ship-to-ship EVAs will then be required, but would not pose any problems as the Constellation Space Suit system, which unlike the current ACES pressure suit worn by Shuttle crews, will then be in place by the first manned Orion flight in 2015, and are capable of emergency microgravity EVAs.
Lunar missions
Although the Apollo 13 was called a "successful failure" because the crew returned safely to Earth using the onboard resources of the Apollo Lunar Module, part of that success was due to the design of the Apollo Service Module. Design around the use of a fuel cell architecture, the cylindrical service module housed the fuel cells, which powered the spacecraft and produced the crew's drinking water, while the liquid oxygen and liquid hydrogen tanks, located almost at the module's mid-section, provided the ingredients to make the cells work. That architecture, along with the decision made by legendary flight director Gene Kranz to use the descent stage engine on the LM Aquarius, led to the crew's safe return to Earth, as the onboard Service Propulsion System would have been useless with the limited battery power in the Command Module, and the damage to the Service Module would have caused a catastrophic failure if the SPS was fired.
With the design of the Orion spacecraft's service module around the use of solar panels, an onboard explosion in the magnitude as that of Apollo 13 would most likely lead to the entire Orion spacecraft, including its heat shield, to become damaged to the point a Columbia-like scenario may occur. In such a case, or if the RCS systems in the Orion service module would malfunction (as it almost occurred on Skylab 3), or any scenario would make travel in the Orion spacecraft unsafe, the Orion/Altair spacecraft will then continue on to the Moon and perform an "Abort-to-Surface" (ATS) maneuver.
With the capability of staying on the Moon for up to 10 days with normal excursions, the ATS maneuver would allow an Orion/Altair crew to use the Moon itself as a "Safe Haven," like that of the ISS for LEO flights, allowing NASA to rush a "Rescue Orion" modified for lunar orbit insertion to the launch pad on an Ares IV or Ares V rocket. Once fueled and cleared by ground crews, the Ares IV or Ares V is launched with the "Rescue Orion," with the spacecraft entering orbit 3 days later. Once the "Rescue Orion" reaches lunar orbit, the crew will then blast off of the lunar surface and perform a docking maneuver similar to that on a nominal Orion/Altair mission, with the crew jettisoning the Altair and firing the AJ-10 engine on the Orion for the return to Earth.
A similar procedure would be followed, once the Lunar Outpost is established, if the Altair is damaged or malfunctions. Current plans call for a crew rotation to occur when a new Altair with a replacement crew arrives. If the old Altair with the outgoing crew fails to fire, then the outgoing crew will then wait at the Lunar Outpost until another Altair is launched to the Lunar Outpost in a manner similar to that of the unmanned "Cargo Altair" flights. Once that Altair reaches the surface, the outgoing crew will then return to lunar orbit in the relieving crew's Altair with the unmanned Altair remaining on the surface for the replacement crew.

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