NASA Office of Logic Design

NASA Office of Logic Design

A scientific study of the problems of digital engineering for space flight systems,
with a view to their practical solution.


NASA SP-504: Space Shuttle Avionics System

Appendix - Acronyms/Abbreviations

AA accelerometer assembly
ac alternating current
ACCU audio central control unit
ADI attitude direction indicator
ADS audio distribution system
ADTA air data transducer assembly
ADU annunciator display unit
AID analog input differential
AIS analog input single-ended
AMI alpha/ Mach indicator
AOD analog output differential
APU auxiliary power unit
ASA aeroservoamplifier
ATC air traffic control
ATU audio terminal unit
ATVC ascent thrust vector control (driver assembly) 
AVVI altitude/vertical velocity indicator
BCE bus control element
BCH Bose-Chaudhuri-Hocquenghen (code)
BFC backup flight controller
BFS backup flight control system
BITE built-in test equipment
bps bits per second
BTU bus terminal unit
BW bandwidth
C&T communication(s) and tracking
C&W caution and warning
CIA controller interface adapter
comsec communications security
CPU central processing unit
CRT cathode-ray tube
D&C display(s) and control(s)
dB decibel
DBC data bus coupler
DBIA data bus isolation amplifier
dc direct current
DDU display driver unit
deg degree
DEU display electronics unit
DIH discrete input high
DIL discrete input low
DISP display function
DK display keyboard
DOD Department of Defense
DOH discrete output high
DOL discrete output low
DPS data processing system
DSC dedicated signal conditioner
DSN Deep Space Network
DU display unit
EADI electronic attitude and directional indicator
ECS environmental control system 
EIU engine interface unit
EMU extravehicular maneuvering unit
EPDC electrical power distribution and control (system)
ET external tank
EVA extravehicular activity
FAA Federal Aviation Administration
FCOS flight computer operating system
FDA fault detection and annunciation
FDI fault detection and identification
FDIR fault detection, isolation, and reconfiguration
FDM frequency-division multiplexer
FM frequency modulation
FO/FS fail operational/fail safe
FRT flight readiness test
ft foot
GCA ground-controlled approach
GCIL ground command interface logic
GN&C guidance, navigation, and control
GNC guidance, navigation, and control MF
GPC general-purpose computer
GPS Global Positioning System
GSE ground support equipment
GSTDN Ground Spaceflight Tracking and Data Network
HAL/S  high-order software language for Shuttle
hemi hemispherical
HLD hybrid load driver
HSI horizontal situation indicator
HUD heads-up display
I/F interface
I/O input/output
ID identification
IDCA inverter distribution and control assembly
ILS Instrument Landing System
IMU inertial measurement unit
IOM input/output module
lOP input/output processor
kbps kilobits per second
KBU keyboard unit
km kilometer
LCA load control assembly
LPS launch processing system
LRU line-replaceable unit
m meter
Mbps megabits per second
MCA motor control assembly
MCDS multifunctional CRT display system
MCIU manipulator controller interface unit
MDA main distribution assembly
MDM multiplexer/demultiplexer
MEC master events controller
MECO main engine cutoff
MF major function
MHz megahertz
MIA multiplexer interface adapter
MM mass memory
MMU mass memory unit
MSBLS microwave scanning beam landing system
MTU master timing unit
navaid navigation aid
n. mi. nautical mile
NRZ nonreturn to zero
NSP network signal processor
OI operational instrumentation
OMS orbital maneuvering system
OPS operational sequence
P/L payload
PASS primary avionics system software
PCA power control assembly
PCM pulse code modulation
PCMMU PCM master unit
PDI payload data interleaver
PI payload interrogator
PIC pyrotechnic initiator controller
PL payload MF
PM phase modulation
PN pseudorandom noise
PROM programmable read only memory
PRS precision ranging system
PSDP payload station distribution panel
PSK phase-shift keying
PSP payload signal processor
quad quadrantal
RCS reaction control system
RF radiofrequency
RGA rate gyro assembly
RHC rotational hand controller
RJDA reaction jet driver aft
RJDF reaction jet driver forward
RM redundancy management
RMS remote manipulator system
RPC remote power controller
RPTA rudder pedal transducer assembly
RTC real-time command
SBTC speed brake thrust controller
SCM subsystem configuration management
SCU sequence control unit
sec second
SGLS Space Ground Link System
SIO serial input/output
SM  system management MF
SMM subsystem measurement management
SPEC  specialist function
SRB solid rocket booster
SSME Space Shuttle main engine
synch synchronization
T-0 time zero
tacan tactical air navigation (system)
TAEM terminal area energy management
TCS test control supervisor
TDM time-division multiplexing
TDRS Tracking and Data Relay Satellite
THC translational hand controller
TV  television
TVC thrust vector control
UHF ultrahigh frequency
USAF U.S. Air Force
VU vehicle utility
WBSC wide-band signal conditioner

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Last Revised: February 03, 2010
Digital Engineering Institute
Web Grunt: Richard Katz
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