R

R

RA: Royal Artillery [not connected to RHA]
RAC: Royal Armoured Corps: all armoured/tank regiments belong to this Corps
RAP: rocket assisted projectile, this is a system that adds rocket propulsion to an artillery shell to give it greater range without increasing the powder charge or the size of the projectile

REC: Regiment Etrangere de Cavalerie (French Legion Cavalry Regiment)
Reinhard: Aktion Reinhard or Einsatz Reinhard in German was the code name given to the Nazi plan to murder Polish Jews in the General Government, and marked the beginning of the most deadly phase of the Holocaust, the use of extermination camps. During the operation, as many as two million people were murdered in Belzec, Sobibor and Treblinka, almost all of whom were Jews.
REG: Regiment Etrangere Genie (French Legion Engineers Regiment)
REI:  Regiment Etrangere D' Infanterie (French Legion Infantry Regiment)
REME: Royal Electrical and Mechanical Engineers
REP: Regiment Etrangere des Parachutists (French Legion Regiment for Paratroopers)

RHA: Royal Horse Artillery
RHA: Rolled Homogeneous Armor; a process of armor manufacturing that ensures its uniformity and enhances resistance to penetration. Often used in the same sense as RHAe.
RHAe: Rolled Homogeneous Armor Equivalent; an equivalent RHA thickness of a given armor package against a given type of threats in terms of penetration resistance. Modern armor packages may be several times more efficient against certain threats than RHA of the same thickness.

RNMAEU: Royal Naval Medical Air Evacuation Unit

Royal Army Service Corps: in charge of distrupting and transportation of stores
Royal Army Ordnance Corps: in charge of distrupting and transportation of ammo

RPG: Rocket Propelled Grenade

RTO: Radio Telephone Operator

RVN: Republic of Viet Nam

update: April 25 2010