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Napisano: 09 Jul 2012 15:57
sistem oznacavanja aviona u mornarici SAD i marincima
Introduction and Explanation
The US Navy used one of the more confusing systems of aircraft designations to be seen during the Second World War. This system contained three main elements and a number of optional elements.
The three main elements were the aircraft class designation, a sequence number specific to a particular aircraft manufacturer and a manufacturer code. This would often be followed by a dash number, reflecting a major sub-type of the aircraft.
The roots of the system in use during the Second World War can be traced back to 1920. In that year a system was introduced in which each type of aircraft was given a two letter code - the first letter to distinguish between lighter-than-air (Z) and heavier-than-air types(V), followed by a second letter to describe the mission responsibility of the aircraft. A fighter aircraft designation would thus start with VF.
This system was modified on 2 January 1934 to allow for multi-purpose aircraft. A third letter could be added to the type designation for the secondary mission duty of an aircraft (thus an aircraft type with the designation VPB would be a heavier than air patrol aircraft with secondary bombing duties.
The list of aircraft class designations in use during at the start of the Second World War was established on 1 July 1939, and contained eleven two letter codes and six three letter codes. During the war at least ten more designations were added to the list. In July 1944 the list was changed against, this time to include a number of sub-codes in brackets.
Next in line was the sequence number specific to a particular manufacture. This was only used for the second and later aircraft of a particular type produced by a particular company (ie the Grumman FF was the first naval fighter produced by that company, the F2F was the second). This is the most confusing part of the system, and things would have been a lot clearer if the sequence numbers had been tied to the aircraft class, not the manufacturer.
The third main part of the code was the manufacturer code, a one letter code, some of which are obvious, others less so.
This produced the distinctive letter-number-letter sequence of US navy aircraft.
Most major aircraft also gained a series of sub-types, distinguished by dash numbers, reaching as high as the F4U-7 for the Corsair. Just to confuse the picture even further, on occasions an aircraft was given a new designation. In this case both the sequence number and dash-number would alter, so the F4U-6 Corsair became the AU-1 when it was redesignated as an attack aircraft. On some occasions a different dash number indicated a very different aircraft, as with the PB4Y-2 Privateer, which was significantly different to the PB4Y-1 Liberator.
There was also a number of prefixes used, the most common of which was X for experimental. This has the capacity to distort alphabetical lists of aircraft types, especially when a particular aircraft never made it past that stage.
This system could produce some apparently illogical results. It is not at all uncommon for an aircraft with a high sequence number to be followed into service by one with a lower number from a different manufacturer (thus the Grumman F6F Hellcat was followed into service by the Chance Vought F4U Corsair). Later in the war when some types of aircraft were being constructed by more than one company virtually identical aircraft could have very different designations (thus the Grumman F4F Wildcat was also produced by Eastern Aircraft as the FM-1). The confusion this system could cause was recognised when the US Navy began to give its aircraft official names.
Aircraft class designations
In practice the V prefix is rarely given. Here we will list the one or two letter class designations as they are normally used.
1939 Codes
B - Bombing
F - Fighting
M - Miscellaneous
O - Observation
P - Patrol
S - Scouting
T- Torpedo
N - Training
R - Transport (Multi-engined)
G - Transport (Single-engined)
J - Utility
OS - Observation-Scouting
PB - Patrol-Bombing
SB - Scouting-Bombing
SO - Scouting-Observation
TB - Torpedo-Bombing
JR - Utility-Transport
Wartime Additions
A - Ambulance
BT - Bombing-Torpedo
SN - Scout-Training
L - Gliders
LN - Training Gliders
LR - Transport Gliders
H - Helicopters
HO - Observation-Helicopters
D - Drones
TD - Torpedo Drones
July 1944
F - Fighters
SB - Scout Bombers
B - Torpedo Bombers
O/S - observation scout
PB - Patrol Bombers
R - Transport
J - Utility
SN - Training
N - Training
K - Drones
KN - Drones (target training)
L - Gliders
LN - Gliders (training)
LR - Gliders (transport)
Subcodes
(M) - Medium or 2 engines (used with F and J)
(HL) - Heavy or 4 engine landplanes (used with PB and R)
(ML) - Medium or 2 engine landplanes
(HS) - Heavy or 4 engine seaplanes
(MS) - Medium or 2 engine seaplanes
Dopuna: 09 Jul 2012 16:09
sistem oznacavanja u armijskom vazduhoplovstvu SAD
Each U.S. Army Air Force (USAAF) aircraft was assigned a unique designation that identified it’s intended purpose, model, series and special purpose. The coding system used during the period 1939 to 1945, (which is still in use today by all branches of the U.S. military), was introduced by the U.S. Army Air Service in May 1924; in 1941 additional characters were introduced to uniquely identify similar aircraft and/or aircraft produced by different manufacturers. The U.S. Air Force was established on 26 Sep 47 and in 1948, a number of prefixes and type symbols were changed notably "P" for pursuit was changed to "F" for fighter; other changes to World War II codes are defined in the following paragraphs.
The USAAF designation system only applied to aircraft ordered by the USAAF and did not apply to foreign aircraft acquired by Reverse Lend-Lease. For example, the Spitfires, Beaufighters, Ansons, etc. acquired from the Royal Air Force (RAF) kept their RAF designation and usually their serial number.
The USAAF/USAF aircraft designation consists of a minimum of three parts and a maximum of six parts. As an example, consider the Douglas TA-20K-15-DO Havoc, msn 23954, USAAF serial number 44-731. The six parts of the designation are indicated by the number in parenthesis shown below:
T A -20 K -15 -DO
(1) (2) (3) (4) (5) (6)
The definitions of the six parts of the designation are:
(1) Status or special-purpose prefix (Optional),
(2) Type symbol (Required),
(3) Model number (Required),
(4) Series letter (Optional; required for the 2d and later aircraft in the series),
(5) Block number (optional), and
(6) Manufacturer identification (required).
Each of these six items are described in detail below in a paragraph numbered 1 through 6 corresponding to the six items above.
1. Status or special-purpose prefix (Optional)
The status or special-purpose prefix indicates the aircraft’s development, status and/or secondary purpose. The first use of this code was the letter "X" indicating an experimental aircraft, usually a prototype. The code was also used for production aircraft that were modified for tests and the aircraft normally retained the X-prefix during the tests. For example, Boeing P-12E, s/n 31-553, was converted to an XP-12E for development tests; when re-engined with an SR-1340E engine, it became YP-12K; when equipped with a supercharger, it became XP-12L; and finally, the aircraft was converted back to a "stock" P-12E.
The second code introduced was "Y" for service test. If tests indicated that the "X" model had promise, the USAAS/USAAC/USAAF would order between 2 and 13 service test aircraft. Many of these were assigned to active duty squadrons who used them to determine their strengths and weaknesses. For example, the USAAC ordered 13 Y1B-17’s; the "1" in Y1B indicated procurement from F-1 Funds rather than regular appropriations. Many of these aircraft were assigned to the 2d Bombardment Group at Langley Field, Virginia for testing. The last pre-World War II code was "Z" indicating obsolete.
The codes used during the period 1939-45 are listed below along with an example of an aircraft using the prefix. This table indicates that the TA-20K-15-DO was an A-20K-15-DO that had been modified as a trainer.
C: Transport (1943 to date) (North American CB-25J Mitchell)
F: Photographic (1945-47) (North American FP-51D Mustang)
K: Ferret (1944-47) (?)
R: Restricted (1942-47) (Lockheed RP-38E Lightning) (see note below)
T: Trainer (1943 to date) (Curtiss TP-40N)
U: Utility (1941 to date) (Cessna UC-78 Bobcat) (see note below)
V: Staff transport (1945 to date) (Boeing VB-17G Flying Fortress)
X: Experimental (1924 to date) (Boeing XB-29 Superfortress)
Y: Service test (1928 to date) (Boeing YB-29 Superfortress)
Z: Obsolete (1928-62) (?)
NOTE: The prefix ”R” indicated that the aircraft was not to be used on combat missions. The codes UC for utility transport or cargo aircraft indicated that the aircraft could accommodate up to eight persons, including pilot, or a cargo weighing no more than 1,400 pounds (635 kg).
2. Type symbol (Required)
The type symbol identifies the basic purpose of the aircraft. For example, our TA-20K-15-DO was basically an attack aircraft ("A") that had been modified into a trainer ("T"). The following letter(s) were assigned during the period 1939-45; examples of an aircraft of each type is indicated.
A: Attack (1926-47; to B in ’48) (Douglas A-26 Invader; to B-26 in ’48)
A: Powered target (1940-41) (Bell A-7 Airacobra)
AG: Assault glider (1942-44) (Timm AG-2)
AT: Advanced trainer (1925-47; to T in ’48) (North American AT-6 Texan; to T-6 in ’48)
B: Bomber (1925 to date) (Martin B-26 Marauder)
BC: Basic combat (1936-40) (North American BC-1)
BG: Bomb glider (1942-44) (Fletcher BG-1)
BQ: Bomb, guided (1942-45) (Boeing BQ-7 Flying Fortress)
BT: Basic trainer (1930-47; to T in ’48) (Vultee BT-13 Valiant; to T-13 In ’48)
C: Transport (1925 to date) (Curtiss C-46 Commando)
CG: Transport glider (1941-47; to G in ’48) (Waco CG-4 Hadrian; to G-4 In ’48)
CQ: Target Control (1942-47; became D-prefix in ’48) (Beechcraft CQ-3 Expeditor; to DC-45 in ’48)
F: Photographic (1930-47; to R-prefix in ’48) (Boeing F-9 Flying Fortress; to FB-17 in ’45 and RB-17 to ’48)
FG: Fuel-carrying glider (1944-47) (Cornelius FG-1)
FM: Fighter, multiplace (1936-41) (Bell FM-1 Airacuda)
G: Gyroplane (1935-39; to O and R in ’39) (Kellett G-1; to R-2 in ’41)
GB: Glide bomb (1942-47)
GT: Glide torpedo (1942-47)
JB: Jet-propelled bomb (1943-47)
L: Liason (1942-62; to O in ’62) (Piper L-4 Cub)
O: Observation (1924-42; to L in ’42) (Piper O-59 Cub; to L-4 in ’42)
OA: Observation, amphibian (1925-47; to A in ’48) (Consolidated OA-10 Catalina; to A-10 in ‘48)
OQ: Target, flying model (1942-47; to Q in ’48) (Frankfort OQ-3; to Q-3 in ’48)
P: Pursuit (1925-47; to F in ’48) (Republic P-47 Thunderbolt; to F-47 in ’48)
PB: Pursuit, biplace (1935-41) (Consolidated PB-2)
PG: Powered glider (1943-47; to G in ’48) (Waco PG-3; to G-3 in ’48)
PQ: Aerial target, manned (1942-47; to Q in ’48) (Culver PQ-14; to Q-14 in ’48)
PT: Primary trainer (1925-47; to T in ’48) (Fairchild PT-14 Cornell; to T-14 in ’48)
R: Rotary wing (1941-47; to H in ’48) (Sikorsky R-5 Dragonfly; to H-5 in ’48)
TG: Trainer glider (1941-47) (Taylorcraft TG-6)
3. Model number (Required)
The model number indicates the number of different models that had been ordered under each type designation, regardless of manufacturer. For example, the B-17 was the 17th bomber design; the P-40 the 40th fighter design; our TA-20K-15-DO was the 20th attack aircraft; etc.
4. Series letter (Optional; required for the 2d and later aircraft in the series)
The series letter was applied to the model number to indicate modifications of the original model. As a general rule, the letters "I" and "O" were not used as series letters. Normally, the first production aircraft did not have a series letter and the second aircraft in the series was given an "A" suffix, e.g., the first production Mustang was the P-51, the second was the P-51A, etc. Today, the first aircraft in the series is assigned the "A" suffix, the second "B", etc.
There were four reasons for changing the series letter, i.e.
1. When a change was made in the engine or engine series,
2. A new propeller of different make or size is fitted,
3. A major change in primary armament is made, and/or
4. A major change is made in structure or equipment installation that affects a model’s interchangeability or flying characteristics.
The modification of the aircraft configuration was not necessarily enough to cause a change in the letter, e.g., P-47D’s were produced in both razorback and bubble canopy versions.
In our example, the TA-20K-15-DO, the series was
A-20: first production aircraft
A-20A: second production aircraft
A-20B: third production aircraft
A-20C: fourth production aircraft
A-20D: projected version with different engines; never built
A-20E: 17 converted A-20A’s with different engines
A-20F: 1 A-20A modified with new armament and turrets
A-20G: fifth production aircraft with solid nose
A-20H: sixth production aircraft
A-20J: seventh production aircraft
A-20K: eighth production aircraft
Therefore, the A-20K was the eighth production aircraft.
5. Block number (optional)
By 1941, the increasing complexity of aircraft made it desirable to identify minor differences between aircraft without changing the series letter. Since these changes were normally made on a number of consecutive aircraft in a particular production block, the term Block Number was used to identify the differences. The Block Number denotes a group of aircraft incorporating the same modifications, the parts of which are interchangeable for maintenance and servicing.
The first block of aircraft are identified by the numeric "-1" as in P-40F-1-CU. Initially, the second block of aircraft were to be identified by "-2" but it was realized that this would preclude identifying field modifications so the second block was identified as "-5" and then by fives, i.e., "-10", "-15", etc. Intermediate numbers were reserved for modifications made in service or at modification centers. The highest block numbers were assigned to Consolidated B-24J-210-CO Liberators.
In our example, the TA-20K-15-DO was one of the 275 Block 15 aircraft built.
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