List of Acronyms and Abbreviations

This list contains definitions for Orbiter or important spaceflight acronyms or abbreviations, especially those appearing in MFDs and various HUD modes.

One entry in this list consists of a term with one or more definitions, like:

Term

Definition

;Term:Definition

Don't use links in the term part of a entry, please do so in the definition part, for keeping a consistent look-and-feel and don't putting to much emphasis on a single definition.

Terms without definitions will get moved to the talk page into the section "Wanted definitions". If you have multiple definitions for a term, the definition part should turn into a numbered list, like:

Term

1. Definition 1
2. Definition 2
3. Definition 3

;Term:
#Definition 1
#Definition 2
#Definition 3

The order of the definitions should be like that:

1. Orbiter HUD definitions
2. Orbiter MFD definitions
3. General Orbiter definitions
4. Orbiter Add-on definitions
5. General spaceflight definitions

If you don't agree to a ordering of definitions, please complain in the talk page about the entry.

See also

• Russian glossary
• List of Acronyms and Abbreviations for the ISS

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Contents: Top - 0–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

A

AgP

Argument of periapsis:The angle in the orbit from the point of the ascending node to the point of periapsis, Used in OrbitMFD.

Alt

altitude, distance from the body surface

AN

ascending node:a vector in an orbit where the body passes from south to north of the plane of reference (i.e. ecliptic or equatorial). Shown in Align MFD and Orbit MFD as a dotted vector line connecting to a solid square on the orbit.

AORP

Autonomous Orbiter Rapid Prototype, a system to allow a shuttle orbiter to land without crew.

ApA

apoapsis apoapsis altitude, the lowest altitude of an orbit. Used in OrbitMFD mode.

ApD

apoapsis apoapsis distance

ApR

apoapsis apoapsis radius

ApT

time to apoapsis in seconds

AR

1. Automatic Reference, used in Align MFD as a command button for Align to select a reference body automatically based on highest gravity
2. Altitude Range, used to manually set the range in the altitude graph in Ascent profile MFD]
3. acceptance review

atmo

atmosphere

ATV

1. Autonomous Transfer Vehicle, an unmanned cargo spacecraft, see ATV.
2. Automated Transfer Vehicle[1]

AU

astronomical unit

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B

BMW

Bate, Mueller, White - authors of Fundamentals of Astrodynamics (1971)

BRG

Bearing, used in the Horizontal Situation Indicator MFD to indicate the compass direction of the ILS or VOR transmitter

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C

CaLV

Cargo launch vehicle, see Ares V

CDI

course deviation indicator

CDR

1. commander
2. critical design review

CEV

Crew expedition vehicle, see CEV

CFD

computational fluid dynamics

CLV

Crew launch vehicle, see Ares I

COAS

Crew Optical Alignment Sight

COM

communication or communicator

CRS

Course, indicates the ship's course (heading) in the Horizontal Situation Indicator MFD

CTD

crash to desktop

CTRL

Control

CTV

1. Crew Transfer Vehicle, a manned spacecraft derived from the ATV, see CTV
2. Compatibility Test Van, NASA

CVEL

1. closing velocity
2. Common Vessel Extensions Light, see CVEL

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D

D3D9

refers to the advanced graphics client in Orbiter.

DDT&E

design, development, test and evaluation

DEV

Deviation, in the Horizontal Situation Indicator MFD, it indicates how far the OBS is adjusted left or right of the radial

DG

Delta-glider

DG4

Orbiter's stock DG

DGIII

DeltagliderIII, a famous enhanced version of the Delta-glider.

DGIV

DeltaGliderIV, an improved version of the DeltaGliderIII.

DG-S

Delta-glider equiped with two scramjets.

Dir

direction

Dist

distance

DIV

divergent, i.e. yaw gimbal mode.

DLng

longitude difference, as seen on the synchronise orbit MFD

DN

descending node

DNP

dynamic pressure

DNS

atmospheric density

DPS

Data Processing System. Term describing the general purpose computers and their interfaces onboard various manned spacecraft.

DST or Dst

distance (to target), used in the Horizontal Situation Indicator MFD to indicate distance to the selected ILS or VOR transmitter

DTe

time to ejection, as seen on the transfer MFD

DTi

time to intercept, as seen on the transfer MFD

DTmin

time of arrical difference, as seen on the synchronise orbit MFD

Dv

delta velocity, as seen on the transfer MFD, see also Delta-V

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E

Ecc

eccentricity

ECL

plane of the ecliptic

ECLSS

Environmental control and life support system

ECSS

european cooperation for space standardization

EELV

Evolved Expendable Launch Vehicle

ELS

ELements, custom Select, used in Align MFD to select a custom orbital elements to which to align.

EQU

plane of the equator

ESA

European Space Agency

ESAS

Exploration Systems Architecture Study

ET

external tank

EVA

Extra vehicular activity, see EVA

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F

FGB

Russian abbreviation for Functional Cargo Block. See FGB

FoV

field of view, as seen in the general information display

FPS

frame rate (frames per second), as seen in the general information display

FRF

Flight Readiness Firing, a launch countdown test of the Shuttle running all except SRB ignition and lift-off.

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G

g

a unit of acceleration. 1g equals the gravity acceleration on earths surface, 9.81 m/s²

GET

Ground Elapsed Time [2]

GL

Used often as vehicle name prefix for a Delta-glider

GLOC

Gravity-induced Loss of Consciousness

GMT

Greenwich Mean Time.See Universal Time on Wikipedia

GPDS

Generic Payload Description System

GPS

Global Positioning System

GS

ground speed

GTO

geostationary transfer orbit

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H

H

Horizon

HAC

Heading Alignment Cone

HLLV

heavy lift launch vehicle

HSI

horizontal situation indicator

HST

Hubble Space Telescope

HTO

hypothetical transfer orbit, as seen on the transfer MFD

HUD

heads up display

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I

IAS

indicated air speed [3]

IDS

instrument docking system, used in Docking MFD

ILS

1. instrument landing system
2. also used in Horizontal Situation Indicator MFD to indicate which runway at which Spaceport is selected by the NAV system
3. International launch services, a US-russian joint venture marketing Atlas and Proton launches

Inc

Inclination, angular difference between one orbit with respect to another, usually the ecliptic, equatorial, or body orbit. Used in Align MFD

ISP

specific impulse

ISS

International Space Station

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J

JD

Julian date

JSC

Lyndon B. Johnson Space Center

JWST

James Webb Space Telescope

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K

KISS

"Keep it simple, stupid!" Famous engineering dogma.[4]

KSC

Kennedy Space Center

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L

LAN

1. Longitude of the ascending node, used in Align MFD
2. local-area network

LCC

1. launch control center
2. life cycle cost

LDEF

Long Duration Exposure Facility

LEO

Low earth orbit

LH2

Liquid Hydrogen

LOCV

Loss of crew and vehicle

LOX

Liquid Oxygen

LPe

longitude of periapsis

L/R

Left/Right, used in Horizontal Situation Indicator MFD to switch MFD mode focus to the left or right graphic display

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M

m

metre

M

Mega (SI prefix for 10⁶). Occasionally mass or mach number

MCC

1. mid course correction
2. mission control center

MCC-H

mission control center Houston

MCC-M

mission control center Moscow

MDR

mission definition review

MECO

main engine cutoff

MET

Mission Elapsed Time. See Mission Elapsed Time on Wikipedia.

MFD

Multifunctional Display, see MFD

MHz

MegaHerz, same as the old term megacycles/second, radio and transponder frequency, used in COMNAV MFD

MJD

modified Julian date

MLP

Mobile Launcher Platform

MMOD

Micrometeorites and orbital debris

MMU

manned maneuvering unit, see MMU

MnA

mean anomaly

MnL

mean longitude

m/s

meters per second, the SI base unit of velocity

MSx

Mission Specialist x

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N

NAV

1. Navigatonal receiver,
   1. in COMNAV MFD it is used to identify up to four receivers in the stack
   2. in Horizontal Situation Indicator MFD, it is used to select which receiver an HSI display is tuned to
2. navigation
3. navigation aid

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O

OAT

outside air temperature

Ob

obliquity of ecliptic (tilt of axis of rotation against plane of ecliptic)

OB+ and OB-

OmniBearing, used to change the offset of the course arrow to left or right of the beam

OBS

omni bearing selector

OBT

orbit, as seen on the orbit MFD

OMBUU

Orbiter Midbody Umbilical Unit

OMP

Orbiter Multiplayer Project, an ongoing program to create a multiplayer server in Orbiter.

OMS

Orbital Maneuvering System, the 'main engines' of the space shuttle orbiter

OS

orbital speed

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P

P

position (sometimes radius) vector, as seen on the align orbital plane MFD

p0

atmospheric pressure at sea level

PAM

Payload Assist Module, a family of solid upper stages for the Space Shuttle

PAPI

Precision Approach Path Indicators, lit runway centerline.

PB

Shuttle PB

PDR

preliminary design review

PDRS

Payload Deployment and Retrieval System, the official name of the robot arm of the Space Shuttle

PeA

periapsis altitude. Altitude of periapsis above the surface of the orbited body

PeD

periapsis distance. See PeR.

PeR

periapsis radius. Distance of periapsis from the center of the orbited body

PeT

time to periapsis in seconds.

PG

1. Page, switching displayed pages in an MFD mode, used in Align MFD
2. prograde

PLT

Pilot

PMI

Principal moments of inertia, see PMI

Pos

position

PRJ

projection, as seen on the orbit MFD

PRR

preliminary requirements review

PSx

Payload Specialist x

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Q

QR

qualification review

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R

R

1. mean radius
2. specific gas constant

r0

atmospheric density at sea level

Rad

1. radial distance
2. angular unit radians

RAnm

true anomaly of reference axis, as seen on the synchronise orbit MFD

Rate

How fast the current orbital plane is changing, degrees per second, used in Align MFD

RCS

reaction control system, spacebourne orientation rocket system.

R&D

research and development

RDT&E

research, development, testing and evaluation

REF

Reference

1. used in Align MFD to select a reference body.

RG

retrograde

RInc

relative inclination, relative inclination between the current and target orbits, used in Align MFD

RKA

Russian Space Agency

RMS

Remote Manipulator System

RS

Russian-side, used as prefix for orientation when describing ISS components.

RSLS

Redundant set launch sequencer, the computer systems responsible for the ignition of the SSMEs in the Space Shuttle orbiter.

RTFM

Read the fine (or many other f-words) manual, a typical forum answer for questions already answered extensivly in the manual.

RTLS

Return to launch site, a Space Shuttle abort mode.

RVel

relative velocity

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S

SAR

1. Search and rescue.
2. Syntetic aperture radar, a radar mode used for creating navigation maps or detect slowly moving ground vehicles.

S/C

spacecraft

SC< and SC>

SCan frequency up or down in the currently selected receiver, used in COMNAV MFD

SDK

Software Development Kit [5]

SDHLV

Shuttle Derived Heavy Launch Vehicle, see Ares V

SDLV

Shuttle Derived Launch Vehicle, see Ares

SECO

1. Secondary Engine Cutoff
2. Sustainer Engine Cutoff

Sim

1. simulation time (in seconds), as seen in the general information display
2. a common abbreviation for "simulator"

SHP

ship, as seen on the orbit MFD

Sh-ToR

ship time-on-reference, as seen on the synchronise orbit MFD

SI unit

The metric system of measurement, the modern name, see SI unit

SL+ and SL-

Select, change which receiver to next or previous receiver to adjust frequency, used in COMNAV MFD

SLF

shuttle landing facility, see Cape Canaveral

SMa

semi-major axis

SMi

semi-minor axis

SRB

Solid Rocket Booster [6]

SRTM

Shuttle radar topography mission, see SRTM.

SSME

Space Shuttle Main Engines [7]

SSTO

Single Stage to Orbit

STOVL

Short take-off, vertical landing. As performed by the DG on full fuel employing hover thrusters during takeoff.

STP

static pressure

STS

space transportation system, AKA space shuttle, see space transportation system

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T

T

orbit period, measured in seconds

TAEM

Terminal Area Energy Management

TAS

true air speed [8]

TEI

Trans Earth Injection[9]

TGT

TarGeT, command button used in Align MFD, Docking MFD, Orbit MFD

Tg-ToR

target time-on-reference, as seen on the synchronise orbit MFD

TKS

russian spacecraft for the Almaz program, see TKS

TLA

Three letter acronym for a three letter acronym.

TLE

two-line elements

TLe

eject longitude, as seen on the transfer MFD

TLi

intercept longitude, as seen on the transfer MFD

TLI

Trans Lunar Injection

Tn

Time to node, used in Align MFD

TOFS

tangential offset docking MFD

TrA

true anomaly

TRK

Track ship, as displayed by map MFD

TrL

true longitude

TRL

technology readiness level

Ts

length of siderial day

TthA

Estimated thrust time at the ascending node to align planes, used in Align MFD

TthD

Estimated thrust time at the descending node to align planes, used in Align MFD

TVEL

tangential velocity

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U

UMMU

Universal manned maneuvering unit, popular add-on, see Universal MMU.

UNKS

unknown problems, you are aware of.

UNK-UNKS

unknown problems, you are not aware of.

UT

universal time, GMT. Not to be confused with UTC (Universial Time Co-ordinated). The latter is based on atomic clocks not astronomy, hence the occasional leap-second to correct UTC to GMT.

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V

VASI

Visual Approach Slope Indicator, the glideslope lighting system ajacent to runways to guide pilots onto the correct angle of glideslope (normally 3 degrees).

VC

1. virtual cockpit
2. Visual C++, an IDE and C++ compiler by Microsoft.

Vel

velocity

VOR

1. very high frequency omnidirectional radio
2. used in the Horizontal Situation Indicator MFD to indicate which VOR transmitter is selected by a NAV radio, if it's selected to a VOR transmitter

VRR

Velocity Radial Range, used to manually set the range in the Radial Velocity graph in Ascent profile MFD

VS

vertical speed

VSA

Virtual Space Agency

VTOL

Vertical Take Off and Landing

VTR

Velocity Tangential Range, used to manually set the range in the Tangential Velocity Range graph in Ascent profile MFD

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W

WBS

work breakdown structure

WPD

work package description

Wrp

time acceleration factor, seen in the general information display

X

XPDR

transponder, used in Docking MFD

Y

YSC

Yokohama Science Center

Z

ZM

zoom, as seen on the map MFD

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Contents: Top - 0–9 A B C D E F G H I J K L M N O P Q R S T U V W X Y Z