| Abbreviation |
Meaning |
| AAC |
Anti-Aircraft Co-operation |
| AACU |
Anti-Aircraft Co-operation Unit |
| AAF |
Auxiliary Air Force |
| AASF |
Advanced Air Striking Force |
| ACU |
Army Cooperation Unit |
| ADF |
Aircraft Delivery Flight |
| ADGB |
Air Defence of Great Britain (= Fighter Command) |
| ADLS |
Air Delivery Letter Service |
| ADRU |
Air Despatch and Reception Unit |
| AFDU |
Air Fighting Development Unit |
| AI |
Airborne Interception |
| ALG |
Advanced Landing Ground |
| AMES |
Air Ministry Experimental Station (i.e. radar station) |
| AOP |
Air Observation Post |
| APC |
Armament Practice Camp |
| A/SR |
Air Sea Rescue |
| ATSU |
Air Transportable Signal Unit |
| ATTDU |
Air Transport Tactical Development Unit |
| Avn |
Aviation |
| BAT |
Blind Approach Training (up to late 42)
Beam Approach Training (as of late 42) |
| B.(D)T.F. |
Bomber (Defence) Training Flight |
| BR |
Bomber Reconnaissance |
| BS |
Bomber Support |
| C & M |
Care and Maintenance |
| CAEU |
Casualtiy Air Evacuation Unit |
| COL |
Chain Overseas Low (radar AMES Type 5) |
| Commo |
Communications |
| CSS |
Combined Signals School |
| CTC |
Combined Training Centre |
| CU |
Conversion Unit |
| Det |
Detachment |
| D/F |
Direction Finding |
| EAC |
Equipment Approvals Committee |
| FAA |
Fleet Air Arm (Naval Aviation) |
| FIU |
Fighter Interception Unit |
| F/R |
Fighter Reconnaissance |
| FSP |
Forward Staging Post |
| FTU |
Flying Training Unit |
| GCI |
Ground Controlled Interception |
| GR |
General Reconnaissance |
| GRU |
General Reconnaissance Unit |
| GSE |
Glider Servicing Echelon |
| HCU |
Heavy Conversion Unit |
| LG |
Landing Ground |
| LRCR |
Long Range Communications Relay |
| LWU |
Light Warning Unit |
| Met |
Meteorological (i.e. Weather) |
| MAEE |
Marine Aircraft Experimental Establishment |
| MCS |
Metropolitan Communications Squadron |
| MPSU |
Mobile Parachute Servicing Unit |
| MTLRU |
Mechanical Transport Light Repair Unit |
| NFDU |
Night Fighting Development Unit |
| N.I. |
Northern Ireland |
| NTU |
Navigation Training Unit |
| OADU |
Overseas Aircraft Despatch Unit |
| OAPU |
Overseas Aircraft Preparation Unit |
| O&RTU |
Operational and Refersher Training Unit |
| OTU |
Operational Training Unit |
| PFF |
Path Finder Force |
| PM&SU |
Parachute Maintenance and Servicing Unit |
| PR |
Photo-Reconnaissance |
| PRU |
Photo-Reconnaissance Unit |
| PTU |
Parachute Training School |
| PWD |
Psychological Warfare Division |
| R&R |
Refueling and Re-Arming |
| RAF |
Royal Air Force |
| RAAF |
Royal Australian Air Force |
| RCAF |
Royal Canadian Air Force |
| RCM |
Radar and Radio Counter-Measures |
| RDF |
Radio Direction Finder (Radar) |
| Recon |
Reconnaissance |
| RIAF |
Royal Indian Air Force |
| RNZAF |
Royal New Zealand Air Force |
| R&SU |
Repair and Salvage Unit |
| SAAF |
South Arican Air Force |
| SO |
Signals Office(r) |
| SOE |
Special Operations Executive |
| STU |
Signals Training Unit |
| TCNVTS |
Transport Command Night Vision Training School |
| TEU |
Tactical Exercise Unit |
| TRE |
Telecommunications Research Establishment |
| TT |
Target Towing |
| UK |
United Kingdom |
| USAAF |
United States Army Airforces |
| W/T |
Wireless Telegraphy |