From the Wiki article you cite:[R-MOD]Darkpowder wrote:There is evidence that this is a design purely developed in the U.S.S.R and not "borrowed" at all. Who knows?
For those who don't understand the US aircraft numeration scheme (it can be very confusing):However, actual resemblance is very superficial as the Su-25 does not use high-bypass engines, and work on what later became the Su-25 began in 1968, four years before YA-9's first flight.
This system was established during WWII, prior to the war aircraft designations were based on manufacturer, so the F-4U Corsair does not fit this scheme, but the P-51D Mustang does.
AB-1C
Where A is a modification or additional role of the aircraft
Where B is the main function of the aircraft
Where 1 is the series number as selected by the Pentagon
Where C is the modification of the aircraft
Examples:
Function letters:
A- Attack A-4D Skyhawk
B- Bomber B-52G Stratobomber
C- Cargo C-5B Galaxy
E- Electronic Warfare E-2A Hawkeye
F- Fighter F-15E Eagle
H- Helicopter H-1U Huey
O- Observation O-1F Bird Dog
P- Pursuit (Old name for Fighters) P-51D Mustang
P- Patrol P-3A Orion
S- Anti-Submarine S-3B Viking
T- Trainer T-38A Talon
U- Utility U-2R
V- VSTOL** AV-8B Harrier
X- Experimental Bell X-1 (1st supersonic airplane)
Variant Letters
A- Attack AH-64A Apache AC-130H Spectre
C- Cargo CH-47D Iroquois (mostly in helicopters)
E- Electronic Warfare EA-6B Prowler EF-111A Raven
F- Fighter FB-111A Aardvark FA-18A Hornet
H- Rescue HH-60J Jayhawk HC-130P Hercules
K- Tanker KC-135A Stratotanker KA-6B Intruder
M- Minesweeper MH-53A Sea Stallion
O- Observation OA-10A Thunderbolt II OA-4D Skyhawk
R- Recon RA-5A Vigilant RF-4B Phantom
S- Special SR-71A Blackbird
Y- Prototype YA-17 (Prototype that became the FA-18 with some modifications)
There may be others I don't know off the top of my head.
