Definitions of Terms

Definition of Common Terms

Line # Acronym Definition

The table on the left contains 84 common terms used throughout the History pages. Feel free to refer back to this table while reading the history pages. You'll find a link at the top of each history page.

AC	Aircraft usually helicopters, primarily UH-I Iroquois B, C, D, H or M model Huey (Bell) helicopters. Slicks were originally B models that in about 1966 were replaced by D and later H models configured as troop lift ships with two M-60, 7.62mm, machine guns mounted one on each side.Guns were B, C or M models (but mostly C) armed with 2.75" rocket pods (normally 7 rockets per pod) and 7.62mm rapid fire mini-guns (3,000 rounds per minute) on each side. There were three basic gunship configurations in the 134^th AHC: Slaughter Ships - which were equipped with mini-guns and 14 rockets. Frogs - which had larger rocket pods, generally 19 rockets per pod, and an M-5 belt-fed 40 mm grenade launcher mounted in a ball aircraft. The M-5 (as well as sometimes the ship itself) was called a Chunker or Thumper. Hogs - which were equipped with all rockets, normally 38 in total. This configuration was often temporarily mounted on a ship when other armament systems were down for maintenance. In its original gun platoon, the 134^th had 6 Slaughter Ships and 2 Frogs or Chunkers (150 & 151). In later years the Frogs were converted to Hogs due to airframe stress problems. Aircraft Commander, the command authority in an aircraft, generally over any other authority regardless of rank, and generally the pilot with the most time in-county, and the most experience, combat flight hours and missions. AC can mean either aircraft commander or aircraft depending on how it is used.
AHC Assault Helicopter Company	This was the most common helicopter unit. It included 31 UH-1's and the equipment and personnel to maintain and repair the aircraft. Each AHC had 2 lift platoons of 11 aircraft each, a gun platoon of 8 aircraft and a service or maintenance platoon with 1 aircraft. There were approximately 300 men in an AHC, including 50-60 pilots. Other types of helicopter units were:
AC AWC	Aerial Weapons Company which had all gunships.
ASHC	Assault Support Helicopter Company. which had CH-47 Chinooks, a large cargo or troop carrying helicopters, and Heavy Helicopter Company which had CH-54 Sky Cranes for very heavy lifting.
AO	Area of Operations, terrain.
ARVN	Army of the Republic of Vietnam soldiers.
Ash & Trash	Any type of non-combat aviation mission. Also called milk runs.
A Team	A 12 man Special Forces (Green Beret) unit that along with local troops manned many small isolated camps, associated with villages, throughout South Vietnam.
Base Camp	A semi-permanent field headquarters and center for a given unit. Base camps usually contain all or part of a unit’s support elements.
Bird	Any aircraft, usually a helicopter.
Bird Dog	Army O-1 two seat, fixed wing aircraft used for aerial observation and spotting for artillery or fighter bombers. Bird dog units were called Recon Airplane Companies (RAC).
Bladder	A heavy duty, rubberized collapsible petroleum drum ranging from 2,000-5,000 gallons in size. Used for aircraft field refueling stations.
Body Bag	The plastic bags used for retrieving bodies on the battlefield.
Bunker	A protective shelter, often underground and made of concrete, or timber and sand bags.
CA	Combat assault (troop insertion or extraction). A fully coordinated airmobile operation often involving artillery preparation of the landing zone.
CAB	Combat aviation battalion, next higher command over a company.
CAV	Nickname for Air Calvary, a recon and scout unit that has aerial scout ships, slicks and gunships as well as its own infantry troops. Also used to refer to armored cavalry which uses M113 APCs and other light armored vehicles.
C&C	Command and Control ship, usually a slick carrying the commander of the unit on the ground.
CE	Crew engineer, or crewchief- the helicopter mechanic that kept it in the air and also manned one of the M-60 machine guns on the ship (usually on the left side).
Central Highlands	A high plateau area covering most of I Corps and II Corps (the northern half of South Vietnam, inhabited mostly by Montagnard tribesmen (a local and relatively backward indigenous people who did not mix with Vietnamese).
Chicken Plate	Nickname for chest protector (body armor) worn by helicopter crewmen. Sometimes sat on by gunners and CE’s to protect other vital parts.
Chinook	The CH-47, twin rotor, cargo helicopter. Also called Shithook or Hook.
CO	Commanding Officer, often called the old man.
Conex	A large metal military container roughly 6'x6'x7' tall, used for shipping and storing supplies and equipment, and often for bunkers, showers, etc.
C Rations	Canned, single meal rations issued for field operations (not very tasty).
DA	Density altitude, the higher the DA, the less lift a helicopter could achieve. Higher temperatures or higher elevation (such as in the central highlands) caused the air to be less dense, resulting in less lift for the rotor blades.
DEROS	Date of Expected Return from Overseas, the date you were allowed to go home.
Dustoff	A nickname for a medical evacuation helicopter or mission, also Medivac.
Elephant Grass	Tall, sharp-edged grass found in the highlands of Vietnam, often reaching 6' tall or more and making judgement of where the ground actually was very difficult for pilots or troops jumping out of the helicopter.
FAC	Usually US Air Force Forward Air Controller but sometimes Army fixed wing.
Firebase	A remote artillery position, usually quite isolated with airlift support being the primary means of resupply.
Fire Team	Usually two gunships that flew together and coordinated their attack so that one ship covered the other as it finished a gun run and turned outbound (its most vulnerable period) from the target. A light fire team was 2 ships and a heavy fire team consisted of 3 ships.
Flack Jacket	Heavy, flexible, fiberglass-filled vest worn for protection from light shrapnel. Different from the Chicken Plate which was much heavier and made of rigid ceramics and metal.
FNG	F***ing new guy.
Free Fire Zone	an area where one could shoot at any target without securing prior permission, often used for “clearing weapons” on the AC to make sure they were working properly.
Grunt	Affectionate name for infantry soldiers or ground pounders—stands for ground replacement not usually trained..
Gunner	helicopter crewman acting as machine gunner. Could be almost anyone but often an aircraft mechanic still learning the job.
HERO	An individual who is respected or revered for their bravery, remarkable accomplishments, or honorable traits. This definition applies to those who served with the 134th Assault Helicopter Company during their operations.
Hootch	House, native hut or GI living quarters.
HQ	any Headquarters unit, also where ever the CO is located.
Huey	The Bell UH-1 Iroquois, generally configured with a 1,400 shaft horsepower Avco Lycoming engine, with a cruising speed of about 100 knots and range of 300 miles, the workhorse of the Vietnam War.
I Corps	Northernmost military region of South Vietnam, beginning south of Danang.
II Corps	II Corps ( 134^thAHC Area of operation.) was the largest tactical zone stretching all the way from Kon Tum province in north west to the southern coast of Binh Thuan. From fighting on jungle covered hills along the tri-border area via the highland plains to the beaches of the south. Being so geographically diversed, both sides had to adapt both its tactics and material.
III Corps	military region from south of Cam Ranh Bay to north of Saigon.
IV Corps	military region from southern tip of Vietnam to north of Saigon.
IFR	Instrument Flight Rules. When flying IFR you can't see the ground or the horizon and must depend on instruments.
IP	Instructor Pilot, authorized to certify other pilots as flight ready. An SIP is a Standards Instructor Pilot who ensures army flight standards and training are being adhered to.
Knots	Nautical miles per hour used for stating aircraft airspeed. The average speed of a Huey is approximately 103-115 mph (90-100 knots). You can use the conversion factor: 1 knot equals 1.15078 mph. So, for 90 knots: 90 knots times 1.15078 mph/knot equals 103.5702 mph. Therefore, 90 knots is approximately 103.57 mph.
KIA	Killed In Action.
DAT	Died After Tour.
LZ	Landing Zone. Hot LZ is one active with enemy fire or expected fire. LZ Prep is to prepare an LZ for landing troops by suppressing enemy fire with gunships, artillery or Air Force jets. Cut an LZ refers to using bombs, especially a special “daisy cutter” that explodes horizontally and clears vegetation.
LRRP	Long Range Reconnaissance Patrols, normally consisting of 4-6 men who were dropped by helicopter in remote areas to observe enemy movements or locate targets. Normally each infantry division or brigade had its own LRRP platoon.
LRRPs	in jargon lrrps also referred to the freeze dried rations that LRRP patrols were issued. They were light-weight and when mixed with hot water were very tasty.
M-16	Standard US Army infantry rifle, firing a 5.56mm bullet.
M-60	most common US Army machine gun, firing a 7.62mm bullet.
MACV	Military Assistance Command Vietnam was created on 8 February 1962, in response to the increase in United States military assistance to South Vietnam. MACV was first implemented to assist the Military Assistance Advisory Group (MAAG) Vietnam, controlling every advisory and assistance effort in Vietnam.
Mama - San	An older Vietnamese woman who was usually employed to do laundry and clean hootches.
Mike Force	Special Forces Mobile Strike Force composed of US leaders and indigenous troops, and used as a reaction or reinforcing unit. Generally battalion size or larger.
Montagnards	Montagnard is an umbrella term for the various indigenous peoples of the Central Highlands of Vietnam. The French term Montagnard signifies a mountain dweller, and is a carryover from the French colonial period in Vietnam.
Nails	2.75" rocket warheads loaded with hundreds of small steel darts called fleshettes.
Napalm	highly flammable explosive (gelled gasoline) used by the Air Force to burn up an area and incinerate enemy troops.
NVA	North Vietnamese Army soldiers/units.
P-38	small GI issue can opener canned C-rations.
Papa San	An older Vietnamese man who usually was employed to do general labor around the compound, including filling sand bags and cleaning latrines.
PIC	Pilot in Command, different from AC in that PIC was whoever was senior between two pilots who had not yet received official unit designations as AC.
PP, Peter Pilot	Affectionate name for co-pilot who was generally considered too inexperienced to be of much use other than to change radios, watch AC gauges and maybe follow the map.
Pop Smoke	To mark a location, LZ or target with a colored smoke grenade. Then a pilot would call out the color to ensure the right location.
Pucker Factor	Gauge of the level of fear or anxiety in the risk or difficulty in a mission.
R&R	Rest and Recuperation, generally out of the country for most people. Grunts could get a little R&R by just NOT being in the field.
Radios	FM radios were used primarily by the infantry, UHF by Army, Navy and Air Force aircraft, and VHF for Army command & control activities, ship-to-ship and local airfield towers. Most helicopters had all three types of radios, sometimes several of each.
RECON	Reconnaissance.
Revetment	Protected parking place for helicopters on an airfield, often an L shaped, two foot wide, dirt-filled wall about 5 foot high to shield the AC from mortar shrapnel.
ROK's	Republic of Korea soldiers. There were about 50,000 ROK troops in II Corps.
RPG	Rifle Propelled Grenade, Russian-manufactured antitank grenade launcher.
Short Final	The last minute or so of an aircraft's flight path as it approaches an airfield or LZ.
Snake	The AH-1 Cobra gunship built specifically for armored attack. Some assault helicopter units had their UH-1 gunships replaced with AH-1's after 1968 or so while other retained the older gunships which were better at providing very close support to ground troops.
Sniffer Mission	Slicks configured with ammonia detection sensors attached to the skids would fly low-level just above the tree tops to detect ammonia given off in urine and perspiration of humans. The strength of the signal allowed one to roughly estimate the number of unseen enemy troops below the jungle canopy.
Sortie	One aircraft takeoff and landing to conduct a mission.
Tailboom	The back end of a Huey beginning just behind the engine compartment.
TOC	Tactical Operation Center, pronounced tock, also called flight ops, the place in an aviation company where flight missions are assigned and posted, a daily and nightly stopping place for crew members.
Tracer	A bullet that leaves a visible trail as it travels from phosphorus packed in a small cavity in its base. US tracers were red and Russian/Chinese tracers were usually green.
Triple canopy	Thickest jungle with vegetation growing at 3 levels, often reaching up more than 50 feet.
VC	Viet Cong, or local guerilla fighters.
WP, Willie Pete	A white phosphorous artillery round or grenade that explodes phosphorus, produces white smoke, and burns whatever it contacts. Usually the last artillery round fired into an LZ when the troop ships are short final is a WP round to signal the pilots that the artillery barrage is over.

Last Modified: Saturday January 11^th, 2025