1924 United States Army Air Service aircraft designation system

In 1924, problems with the previous designation system led to a general revamping of the designation system used by the United States Army Air Service. This system was to remain in effect with the U.S. Army Air Corps, the U.S. Army Air Forces and the independent U.S. Air Force, as well as those aircraft remaining in the U.S. Army after 1947. With some minor changes it became the basis of the 1962 United States Tri-Service aircraft designation system.

1924–1962 Designation System

The designation given to a particular aircraft can be broken down to provide information about that specific aircraft. A hypothetical example shows a typical designation, and what each section is. Tables below indicate possible codes used for each section, what their meanings were, and the time period in which they were used – not all codes were in use at the same time, and some codes, such as P for pursuit were changed to F for fighter for a given aircraft while they were in service, so that the Lockheed P-80 was redesignated as the Lockheed F-80. The portion of the designation after the subtype may be omitted in normal use. The hyphen before the block number may be replaced with the word "block", and in some cases the block number may be omitted. This information, along with the name of the service (USAAC, USAAF, USAF), the base (if permanently assigned) and the serial number was painted on the forward fuselage side under the cockpit.

Status	Mission-Modifier	Mission-	Model	Subtype	-Block Number	-Production Facility Code
X	W	B-	29	A	-10 or  Block 10	-BO

Status Prefix

(generally applied only to specific aircraft)

Code	Meaning	Period
E	Exempt from modification orders (loaned to outside organizations)	1946–1955
G	Grounded permanently (for groundcrew instruction)	1924–1962
J	Temporarily modified for Special Tests (e.g. NACA)	1956–1962
N	Permanently modified for Special Tests (e.g. NACA)	1956–1962
R	Restricted (e.g. no aerobatics, no passengers or similar)	1943–1947
X	Experimental pre-production development aircraft	1925–1962
Y	Service test pending production orders	1928–1962
Y1	Funding from outside normal fiscal year procurement	1931–1936
Z	Obsolete - limits maintenance and repairs	1928–1962

Mission Modifier prefix

Used when an aircraft has been modified for a different role from originally designed.

Code	Meaning	Period
C	Cargo Transport	1943–1962
D	Director (Drone Controller)	1948–1962
F	Photographic	1945–1947
G	Carrier (parasite aircraft mothership)	1948
K	Ferret (electronic intelligence)	1944–1947
K	Tanker	1949–1962
M	Medical	1951–1952
P	Passenger Transport (Only)	1948–1962
Q	Radio Controlled Drone	1948–1962
R	Reconnaissance (Photographic)	1948–1962
S	Search and Rescue	1948–1962
T	Trainer	1943–1962
U	Utility (light transport)	1943–1962
V	VIP Transport	1945–1962
W	Weather	1948–1962

Mission Letter

Code	Meaning	Period
A	Aerial Target	1940–1941
A	Amphibian	1948–1962
A	Attack	1924–1947
AG	Assault Glider	1942–1944
AT	Advanced Trainer	1925–1947
B	Bomber	1925–1962
BC	Basic Combat	1936–1940
BG	Bomb Glider	1942–1944
BLR	Bomber, Long Range	1935–1936
BQ	Bomb, Controllable (glide bombs & cruise missiles)	1942–1945
BT	Basic Trainer	1930–1947
C	Cargo	1925–1962
CG	Cargo Glider	1941–1947
CQ	Target Control	1942–1947
F	Fighter	1948–1962
F	Photographic	1930–1947
FG	Fuel Glider	1930–1947
FM	Fighter, Multiplace	1936–1941
G	Glider	1948–1962
G	Gyroplane	1935–1939
GB	Glide Bomb	1942–1947
GT	Glide Torpedo	1942–1947
H	Helicopter	1948–1962
HB	Heavy Bomber	1925–1927
JB	Jet-Propelled Bomb	1943–1947
L	Liaison	1942–1962
LB	Light Bomber	1924–1932
O	Observation	1924–1942
OA	Observation Amphibian	1925–1947
OQ	Aerial Target (Model Airplane)	1942–1947
P	Pursuit	1925–1947
PB	Pursuit, Biplace	1935–1941
PG	Powered Glider	1943–1947
PQ	Aerial Target (Man Carrying)	1942–1947
PT	Primary Trainer	1925–1947
Q	Aerial Target	1948–1962
R	Reconnaissance	1948–1962
R	Rotary Wing	1941–1947
S	Supersonic/Special Test	1946–1947
T	Trainer	1948–1962
TG	Training Glider	1941–1947
U	Utility	1952–1962
V	VTOL or STOL	1954–1962
X	Special Research	1941–1947

Model Number

In theory each new design in a specific Mission category is numbered in sequence starting at 1, so that succeeding designs are numbered 2,3,4 etc. however numbers were occasionally skipped.

Sub-type

Minor modifications to a basic design are usually given a sequentially assigned letter denoting the particular subtype, starting with A and continuing with B, C, D, etc. In general, no additional meaning can be deduced from the sub-type letter.

Block Number

Analogous to the order number, these help not just to identify when an airframe was built, but in some types distinguish changes that occurred during production not identified by the sub-type letter, as between the Republic P-47 Thunderbolt razorback variant and the bubble canopy variant. Block numbers are unique to each type of aircraft.

Production facility code

Each factory producing aircraft for the USAAF was assigned a two letter code to distinguish between the product of one facility from another. This was important because parts were not always interchangeable between different plants, and the aircraft may have required different modifications during service.

Code	Manufacturer	Location
AD	Aero Design & Engineering Co.	Bethany, OK
AE	Aeronca	Middletown, OH
AG	Air Glider	Akron, OH
AH	American Helicopter	Manhattan Beach, CA
AV	Avro Canada	Montreal, QC, Canada
BA	Bell	Atlanta, GA
BB	Babcock Aircraft	DeLand, FL
BC	Bell Aerosystems	Buffalo, NY
BE	Bell	Buffalo, NT
BF	Bell	Fort Worth, TX
BH	Beech	Wichita, KS
BL	Bellanca	New Castle, DE
BN	Boeing	Renton, WA
BO	Boeing	Seattle, WA
BR	Briegleb Sailplane	Beverley Hills, CA
BS	Bowlus	San Francisco, CA
BU	Budd	Philadelphia, PA
BV	Boeing-Vertol	Morton, PA
BW	Boeing	Wichita, KS
CA	Chase Aircraft	West Trenton, NJ
CC	Canadian Commercial Corp.	Toronto, ON, Canada
CE	Cessna	Wichita, KS
CF	Convair/Consolidated-Vultee	Fort Worth, TX
CH	Christopher Aircraft	St. Louis, MO
CK	Curtiss-Wright	Louisville, KY
CL	Culver	Wichita, KS
CM	Commonwealth Aircraft	Kansas City, MO
CN	Chase Aircraft	Willow Run, MI
CO	Convair/Consolidated-Vultee	San Diego, CA
CR	Cornelius	Dayton, OH
CS	Curtiss-Wright	St. Louis, MO
CU	Curtiss-Wright	Buffalo, NY
CV	Chance Vought, Vought	Dallas, TX
DA	Doak Aircraft	Torrance, CA
DC	Douglas	Chicago, IL
DE	Douglas	El Segundo, CA
DH	De Havilland Canada	Toronto, ON, Canada
DJ	SNCA Sud-Ouest	Marignane, France
DK	Douglas	Oklahoma City, OK
DL	Douglas	Long Beach, CA
DM	Doman Helicopter	Danbury, CT
DO	Douglas	Santa Monica, CA
DT	Douglas	Tulsa, OK
FA	Fairchild	Hagerstown, MD
FB	Fairchild	Burlington, NC
FE	Fleet	Fort Erie, ON, Canada
FL	Fleetwings	Bristol, PA
FO	Ford	Willow Run, MI
FR	Frankfort	Joliet, IL
FS	Firestone	Los Angeles, CA
FT	Fletcher Aviation	Pasadena, CA
GA	G & A Aircraft	Willow Grove, PA
GC	General Motors (Fisher)	Cleveland, OH
GE	General Aircraft	Astoria, Long Island, NY
GF	Globe	Fort Worth, TX
GK	General Motors	Kansas City, KS
GM	General Motors (Fisher)	Detroit, MI
GN	Gibson Refrigerator	Greenville, MI
GO	Goodyear Aircraft	Akron, OH
GR	Grumman	Bethpage, Long Island, NY
GT	Grand Central Aircraft Eng.	Tucson, AZ
GY	Gyrodyne Co., of America	St. James, Long Island, NY
HE	Helio	Norwood, MA
HI	Higgins Aircraft	New Orleans, LA
HI	Hiller	Palo Alto, CA
HO	Howard Aircraft	Chicago, IL
HP	Handey Page	Radlett, Herts, UK
HS	Hawker Siddeley Aviation	Kingston, Surrey, UK
HU	Hughes Aircraft	Culver City & San Diego CA
IN	Interstate A. & Eng.	El Segundo, CA
KA	Kaman	Windsor Locks, CT
KE	Kellet	Philadelphia, PA
KM	Kaiser Manufacturing	Willow Run, MI
LK	Laister-Kauffman	St. Louis, MO
LM	Lockheed Aircraft	Marietta, GA
LO	Lockheed Aircraft	Burbank, CA
MA	Martin	Baltimore, MD
MC	McDonnell	St. Louis, MO
MD	Martin	Baltimore, MD
MF	Martin	Orlando, FL
MH	McCulloch Motors	Los Angeles, CA
MM	McDonnell	Memphis, TN
MO	Martin	Omaha, NE
NA	North American	Inglewood, CA
NC	North American	Kansas City, KS
ND	Noorduyn Aviation	Montreal, QC, Canada
NF	North American	Fresno, CA
NH	North American	Columbus, OH
NI	North American	Downey, CA
NK	Nash-Kelvinator	Detroit, MI
NO	Northrop	Hawthorne, CA
NT	North American	Dallas, TX
NW	Northwestern Aeronautical Co.	St. Paul, MN
OM	On Mark Engineering	Van Nuys, CA
PA	Piper	Lock Haven, PA
PH	Piasecki	Morton, PA
PI	Piper	Lockhaven, PA
PI	Piasecki	Philadelphia, PA
PL	Platt-LePage	Eddystone, PA
PR	Pratt, Read & Co.	Deep River, CT
RA	Republic	Evansville, IN
RD	Read-York	Kenosha, WI
RE	Republic	Farmingdale, Long Island, NY
RI	Ridgefield Mfg.	Ridgeville, NJ
RO	Robertson Aircraft	St. Louis, MO
RP	The Radioplane Co.	Van Nuys, CA
RY	Ryan Aeronautical	San Diego, CA
SA	Stroukoff	West Trenton, NJ
SE	Seibel Helicopter	Wichita, KS
SI	Sikorsky Aircraft	Stratford, CT
SL	St. Louis Aircraft	St. Louis, MO
SP	Spartan	Tulsa, OK
SW	Schweizer	Elmira, NY
TA	Taylorcraft	Alliance, OH
TE	Temco	Dallas, TX
TG	Texas Engineering & Manufacturing	Greenville, TX
TI	Timm	Van Nuys, CA
TP	Texas Engineering & Manufacturing	Grand Prairie, TX
UH	United Helicopter	Palto Alto, CA
UN	Universal Molded Products	Bristol, VA
VE	Vega Aircraft Corp.	Burbank, CA
VI	Canadian Vickers	Montreal, Canada
VL	Vertol Aircraft	Morton, PA
VN	Vultee	Nashville, TN
VO	Chance Vought	Dallas, TX
VU	Vultee	Downey, CA
VW	Vultee	Wayne, MI
WA	Ward Furniture Co.	Fort Smith, AR
WI	Wichita Engineering	Wichita Falls, TX
WO	Waco	Troy, OH

Exceptions

Aircraft ordered by foreign governments but taken over by the US Government often used the manufacturer's internal designations rather than the designation used for similar aircraft ordered by the US Government, so that the Consolidated LB-30 was a B-24 ordered by the British but not delivered, and the Vultee V.77 was similarly an AT-19.

Bibliography

Websites

• Andrew Chorney (2007). "U.S. Systems of Aircraft Designation". Retrieved 24 May 2012.
• Derek Bridges (2005). "U.S. Military Aircraft Designation Systems". Archived from the original on 4 March 2016. Retrieved 24 May 2012.
• Andreas Parsch (2006). "Current Designations of U.S. Military Aircraft". Retrieved 24 May 2012.
• Randy Wilson (1997). "U. S. Army Aircraft Designations 1939-1945". Retrieved 24 May 2012.

Books

• Fahey, James C. (1946). U.S. Army Aircraft (Heavier-Than-Air) 1908-1946. New York, N.Y., Ships and Aircraft.
• Swanborough, Gordon; Bowers, Peter M. United States Military Aircraft Since 1909. Putnam.