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Apollo 14

Abbreviations and acronyms:

Corrected Transcript and Commentary Copyright © 2003 by W. David Woods and Ronald Hansen. All rights reserved.
Last updated 2017-02-17

AOS

Acquisition Of Signal
The spacecraft has reacquired radio contract with Mission Control. In Earth orbit this happens when the spacecraft appears above the horizon of a communications station. At the Moon, this happens when the spacecraft reappears from behind the Moon. During the coast phase to and from the Moon, the spacecraft is in almost continuous contact with one of the main ground stations.

APS

Ascent Propulsion System (LM) or Auxiliary Propulsion System (S-IVB)
It's either the main engine system of the ascent (upper) stage of the LM, or the attitude control system of the third stage of the Saturn V.

ARIA

Apollo Range Instrumentation Aircraft
These aircraft were used as relays for communications and telemetry between the spacecraft and Houston. Although not as capable as fixed ground stations or ships, they could be quickly deployed to anywhere they were needed.

BEF

Blunt End Forward
The spacecraft was flying backwards as opposed to SEF (sharp end forward).

BMAG

Body-Mounted Attitude Gyro
A set of rate gyros use to measure how fast the spacecraft is turning around its pitch, roll, and yaw axes.

BPC

Boost Protective Cover
See launch escape system.

CDR

Commander
The leader of the spacecraft crew.

CG

Center of Gravity
A theoretical point at which all the mass of an object is concentrated.

CM

Command Module
The part of the Apollo spacecraft where the astronauts live and work during their flight to the Moon and back. Its also the only part that can reenter the Earth's atmosphere.

CMC

Command Module Computer
The command modules control and navigation computer.

CMP

Command Module Pilot
The crew member responsible for flying and running the command module (CM).

CMS

Command Module Simulator
A computer controller replica of the CM used for training and trying out new CM procedures.

COAS

Crew Optical Alignment Sight
A window mounted sight used by the command module pilot to line up with the lunar module during docking.

COI

Contingency Orbit Insertion
If the S-II stage has burned long enough, orbit can still be reached even if the S-II stage doesn't finish its burn. If the S-IVB has burned long enough, even if it doesn't finish its burn, orbit can be reached using the SPS engine.

CSM

Command and Service Modules
For most of a flight, the command and the service modules work together as one spacecraft. Just before the landing, the command module separates from the service module and brings the astronauts back to Earth.

DAC

Digital to Analog Converter
Converts digital signals into analog signals.

DAP

Digital Autopilot

Delta P

Delta Pressure
The difference in pressure, usually in pounds per square inch (PSI) between the CM and the LM.

Delta V

Delta Velocity
The difference between two velocities, usually due to a burn.

DET

Digital Event Timer

DOI

Descent Orbit Insertion
The DOI burn lowered the perilune far enough to permit the actual landing to be started when the spacecraft reached the perilune.

DPS

Descent Propulsion System
The LM propulsion system used during the lunar landing.

DSE

Data Storage Equipment
A system that recorded spacecraft data and the conversations of the astronauts.

DSKY

Display and Keyboard
This was the computer's input/output device. Although the computer didn't have a mouse, it did have two hand controllers, the RHC and the TVC.

ECA

Electronic Control Assembly

ECS

Environment Control System
More than just air conditioning, it also provided the crew with oxygen and water while eliminating carbon dioxide and waste water.

EDS

Emergency Detection System
An onboard system that monitored the launch and the launcher looking for serious problems that would require the launch to be aborted.

EECOM

Electrical, Environmental, and Communications controller
The man in MOCR (mission control) who looked after these subsystems during a flight.

EFH

Earth Far Horizon
The whole Earth is too big to be used as a navigation fix.

EMS

Entry Monitor Subsystem
Its primary job was to monitor the reentry phase of a mission, it was also used to measure the delta V of a burn.

EPS

Electrical Power Subsystem
Provided the other spacecraft systems with electrical power.

FDAI

Flight Director Attitude Indicator
An artificial horizon that allowed the astronauts to keep track of where the spacecraft was pointing.

FIDO

Flight Dynamics Officer
The man in the MOCR (mission control) who was responsible for the spacecraft's trajectory.

GDC

Gyro Display Coupler

GET

Ground Elapsed Time
Nominally the time since launch, used for timing all mission events.

G/N or G&N

Guidance and Navigation

GPI

Gimbal Position Indicator
Shows the astronauts where the SPS engine gimbals are positioned so they can verify that the engine is pointing in the right direction before and during a burn.

IMU

Inertial Measurement Unit
The IMU measures the amount and direction of the change in velocity of the spacecraft during burns.

IU

Instrument Unit
See instrument unit

KSC

Kennedy Space Center

IVT

Intra-vehicular Transfer
Moving between the CM and the LM.

LEB

Lower Equipment Bay
The second work place inside the CM, located just past the feet of the couches. This is where the telescope and sextant are located.

LES

Launch Escape System
Sometimes called the launch escape tower (LET), it's attached to the top of the CM during the first part of the launch. In case of a launch abort, it will pull the CM away from the launch vehicle and position the CM for a safe landing. See Launch Escape System for more details

LET

Launch Escape Tower
See LES

LGC

Lunar module Guidance Computer
The lunar modules control and navigation computer.

LH2

Liquid Hydrogen

LM

Lunar Module
The lunar lander

LMP

Lunar Module Pilot
The LM systems expert. The spacecraft commander actually flew the LM.

LMS

Lunar Module Simulator
A computer controlled replica of the LM used for training and trying out new LM procedures.

LOI

Lunar Orbit Insertion
The long burn performed behind the Moon to slow the spacecraft enough to enter into lunar orbit.

LOR

Lunar Orbit Rendezvous
The process of bringing the CSM and LM back together after they have separated in lunar orbit.

LOS

Loss Of Signal
The spacecraft is out of radio contact with the ground because it's either below the horizon of all of the communications stations or it's behind the moon.

LOX

Liquid Oxygen

LTC

Hycon Lunar Topography Camera
A movie camera used to document future landing sites and areas of scientific interest.

LUT

Launch Umbilical Tower

LVDC

Launch Vehicle Digital Computer
Located in the instrument unit, it controlls the launch vehicle.

Max q

Maximum dynamic pressure (q)
A very critical point during a launch when a rocket is experiencing the maximum aerodynamic loads.

Launch Vehicle

The Saturn V launcher
The term, however, is not specific to the Saturn V and can be used for any rocket.

MCC

Mission Control Center
Often just called Mission Control.

MTVC

Manual Thrust Vector Control
The SPS engine of the CSM uses a set of gimbals to control the thrust direction during a burn. Although this is usually done automatically, the astronauts can control it manually with the rotational control.

OJT

On the Job Training
Also "learning by doing". Often a subtle way of saying that the training was insufficient.

OPS

Oxygen Purge System
An emergency oxygen system that the astronauts carry on top of their backpacks during their Moon walks.

ORDEAL

Orbital Rate Drive Electronics Apollo LM
When the spacecraft is in orbit around the Earth or the Moon, the ORDEAL can be used to control the FDAI so that it will show where the horizon is.

P00

Null (do nothing) program
This program is just an idle, do-nothing loop. However, it needs to be running whenever the computer is being updated from the ground.

P52

Realign the guidance platform program
A program that ran both on the CMC and the LGC to realign each spacecrafts guidance platform.

PCM

Pulse Code Modulation
Digital data transmission.

PDI

Powered Descent Initiation
The actual lunar landing which used the LMs DPS to brake the LM out of orbit and land it softly on the lunar surface.

PIPA

Pulsed Integrating Pendulous Accelerometer
A very accurate instrument for measuring changes in the spacecraft velocity.

PTC

Passive Thermal Control
The slow rotation of the spacecraft to made sure that no part of it gets either too hot or too cold. Also called "barbecue mode".

PUG

Propellant Utilization Gauging
Part of the system that controls the mixture ratio of the SPS engine to ensure that the fuel and oxidizer are being burned at the correct rates. This not only optimizes the thrust of the engine, but also avoids having excessive amounts of fuel or oxidizer left over in the tanks.

PUGS

Propellant Utilization Gauging System
See above.

RCS

Reaction Control System
The CM, LM, and SM had groups of small thrusters that were used to control the attitude of the spacecraft and in the case of the LM and SM, were also used to make small changes in the flight path.

REFSMMAT

Reference to Stable Member Matrix

RHC

Rotation Hand Control
A joy stick used to manually control the attitude of the spacecraft.

SCS

Stabilization and Control System
The system that controlled the spacecraft attitude (where it was pointing).

SEF

Sharp End Forward
The CSM is flying with its nose pointing in the direction of flight.

S-IC

Saturn V's first stage
See S-IC description for more details.

S-II

Saturn V's second stage
See S-II description for more details.

S-IVB

Saturn V's third stage
See S-IVB description for more details.

SM

Service Module
The large cylindrical back end of the spacecraft with the large SPS engine bell at its far end.

SPS

Service Propulsion Subsystem
The main propulsion system of the CSM.

TCA

Time of Closest Approach
Time when the spacecraft comes closest to a ground target.

TEI

Transearth Injection
The SPS engine burn that took the spacecraft out of lunar orbit and send it back towards the Earth.

THC

Translation Hand Controller
This hand controller was used by the astronauts to move the spacecraft.

TLI

TransLunar Injection
This was the second burn of the third stage (S-IVB) of the Saturn V which took the spacecraft out of Earth orbit and sent it towards the Moon.

TM

Telemetry
Spacecraft data that's automatically send to the ground.

TVC

Thrust Vector Control
This system aligns the thrust vector of the SPS engine with the center of gravity of spacecraft. In simple terms, it keeps the SPS engine from turning the spacecraft during burns.



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