The
Orion Multi-Purpose Crew Vehicle (Orion MPCV) is equipped with a
launch escape system
A launch escape system (LES) or launch abort system (LAS) is a crew-safety system connected to a space capsule that can be used to quickly separate the capsule from its launch vehicle in case of an emergency requiring the abort of the launch, suc ...
. Orion has several abort modes. Some of these may not use the LAS itself, but would use the second stage of the SLS, or even the Orion vehicle's own propulsion system (the
Aerojet AJ10
The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne (previously Aerojet). It has been used to propel the upper stages of several launch vehicles, including the Delta II and Titan III. Variants were and are used as the servi ...
engine) instead.
Modes
The method of abort, either using the LAS or the second stage of the
Space Launch System(SLS) booster, depends on how far into the flight the spacecraft and crew are traveling.
Prelaunch
NASA has acquired several
MRAP
Mine-Resistant Ambush Protected (MRAP; ) is a term for United States Armed Forces, United States military light tactical vehicles produced as part of the MRAP program that are designed specifically to withstand improvised explosive device (IE ...
s to station near the launch pad, should there be time for the crew to evacuate the vehicle. One will be occupied by emergency rescue personnel, while the other will stand empty behind a
blast shelter
A blast shelter is a place where people can go to protect themselves from blasts and explosions, like those from bombs, or in hazardous worksites, such as on oil and gas refineries or petrochemical facilities. It differs from a fallout shelter, ...
. Pad emergency egress enables astronauts and engineers to quickly escape the perimeter of the rocket. Both zip-lines and roller coasters were at one time studied for this purpose.
Mode one
During the first 120 seconds of flight, up to the jettisoning of the solid-fueled boosters at , the Orion crew module (CM) will separate from the rest of the rocket propelled by the LAS. Unlike the Apollo Launch Escape System, which used a pair of
canards and the weight of the spacecraft to flip the vehicle over for landing, the Orion LAS has a set of steering rockets that will steer the spacecraft away from the malfunctioning
SLS, as well as prepare the spacecraft for both separation and splashdown. The tower will then be jettisoned 14 seconds later and the
hypergolic
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other.
The two propellant components usually consist of a fuel and an oxidizer. T ...
fuel on the Orion CM would be automatically released at a pre-determined altitude.
Mode two
After the LAS is jettisoned, the Orion will separate as a whole from the SLS and either use its large
AJ-10
The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne (previously Aerojet). It has been used to propel the upper stages of several launch vehicles, including the Delta II and Titan III. Variants were and are used as the ser ...
engine or smaller control engines to maneuver from the rocket. Similar to a Space Shuttle
trans-Atlantic (TAL) abort profile, the Orion will use the AJ-10 engine to propel the spacecraft to a desired separation point, in which then the Orion CM would land in either western
Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, i ...
or
Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria t ...
on "due east" (i.e., lunar) flights, or in
Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
or the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...
on
ISS
The International Space Station (ISS) is the largest modular space station currently in low Earth orbit. It is a multinational collaborative project involving five participating space agencies: NASA (United States), Roscosmos (Russia), JAXA (J ...
-bound flights. A splashdown in the eastern
Atlantic Ocean
The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...
would only be a contingency.
Mode three
The SLS would propel the Orion into an initial orbit, upon which the spacecraft will immediately separate, and then perform a retrofire that will allow the Orion CM to splashdown in the
Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the contin ...
off the U.S. West Coast, or make a ground landing at either
Edwards Air Force Base in California or
White Sands Space Harbor
White Sands Space Harbor (WSSH) is a spaceport in New Mexico that was formerly used as a Space Shuttle runway, a test site for rocket research, and the primary training area used by NASA for Space Shuttle pilots practicing approaches and landin ...
in New Mexico. This is similar in profile to the Shuttle's ''abort once around'' (AOA) profile.
Mode four
If the SLS suffers less-than-ideal performance during the initial orbit insertion, it can be restarted 45 minutes later to place the Orion into a less than ideal orbit that can be corrected with the on-board propellant reserves later in the flight. This is similar to the Shuttle's ''Abort To Orbit'' (ATO) profile, but depending upon the stable orbit reached, it may require NASA to end the mission with a landing at either Edwards or White Sands within a 24-hour period.
See also
*
Space Shuttle abort modes
Space Shuttle abort modes were procedures by which the nominal launch of the NASA Space Shuttle could be terminated. A pad abort occurred after ignition of the shuttle's main engines but prior to liftoff. An abort during ascent that would resul ...
*
Apollo abort modes
Apollo abort modes were procedures by which the nominal launch of an Apollo spacecraft, either the Saturn IB or Saturn V rocket, could be terminated. The abort of the flight allowed for the rescue of the crew if the rocket failed catastrophicall ...
*
Soyuz abort modes
References
Full ESAS reportAugust 2007 official NASA document€”NASA has not completely abandoned the "land landing" option
{{Project Constellation
Constellation program
Orion (spacecraft)