Hi Everyone. I have a question that I have always wondered since I have been intrested in aircraft. In the names of some aircraft there is a Y in front of the F. For example: The YF-22 Raptor. Can someone tell me what the Y stands for?

Thanks everyone

The 'Y' denotes that the aircraft has a Prototype status. You can see a list of all possible letter codes involved in the US Tri-Service system on our definitions page

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~JetWhiz

Saturday, August 29, 2009 -- 6:40:49 PM PDT

no x means that

actually there is a difference. X is actually pointing towards an experimental aircraft. not necessarily a combat aircraft (in fact i can only think of a few instances where that happened. that was the JSF) Y is actually used for Young (i think) Fighter. so you get Young Fighter 22. this is used when the aircraft is competing for a contract like with the YF-16 and YF-17. or in this case, the YF-22, and YF-23. as soon as whichever aircraft is decided the winner, the Y is dropped and you just get F-22.

That's correct, but Y can be used to designate any aircraft whose status is a prototype (not just fighters). When we're talking about X in terms of an aircraft's status it is referring to designs thrown together for experimental testing (such as testing if a conceptual airframe actually works as expected). The Y status designation, however, addresses aircraft that are nearly ready for production (they are prototypes for the production release). Typically you build experimental models (sometimes many of them) before actually building a prototype.

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~JetWhiz

Wednesday, September 30, 2009 -- 6:49:35 PM PDT

The X- designation can mean a number of things, it generally stands for experimental, however an aircraft with the X- designation can still become a production aircraft without officially having a YF-, YB-, etc designation. Take the X-32 and X-35 for instance. The X-35 after winning the contract essentially went straight to the F-35 designation. However, the F-22, was the YF-22 prior to becoming the F/A-22.

The actual designation meanings are:
X - Experimental
Y - Prototype

Very true, there are no requirements to have official aircraft status designations start at X and then Y before going to production; there were no official XF-22 aircraft released before the prototype was shown to the USAF.

There are two different meanings to 'X' in an aircraft designation:

• the basic mission can be experimental (such as the X-1, X-15, etc.)
• the status of an aircraft can be experimental (like the XF-11 and XF-89)

The X-35 has a basic mission of experimental (not fighter) ... it was an experimental aircraft (not a fighter with experimental status). If it were a fighter with experimental status then it would have been the XF-35. In that sense, there were no XF-35 and YF-35 aircraft made -- just a fully experimental aircraft that led to a production aircraft.

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~JetWhiz

Saturday, October 03, 2009 -- 3:56:01 PM PDT

True, the clarify on the basic mission portion of the 'X' designation. Just because it does not have another designation 'F' for instance, does not mean it was not designed for a more specific purpose. Generally, in cases that lack that 'F' or any other secondary designation the aircraft's fate is still undecided. In the X-35's case, it may have been beat by the X-32, leaving it an 'X' and sending it to the bone yard or a museum. Where as, it won the competition and became the F-35.

Also, please understand that this is all based off of the previously mentioned Tri-Service Aircraft Designation System, which was introduced in 1962. That being said, there have been a number of instances where the system was changed and/or disregarded when naming aircraft.

firstsgt_cap, jetwhiz, f6hellcat are all correct. By the way, f6hellcat, why is your picture familiar?