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Hello to everyone,

I've noticed there seems to be alot of concern over the F-22's weight in some sectors of the defense community, because it is heavier than the F-15C it is replacing, and analysts have said that dogfighting capability may be diminished. Where does all this weight come from? Because electronics have been getting smaller and lighter all these years, and I don't think that's the issue.
Another thing that is interesting is that, while many people and so called "experts" have said that the Su-27 family is more maneuverable than the F-22, the Su-27 and all of its derivatives actually weigh (empty weight) more than the F-22. So what gives? Is maneuverability really influenced so profoundly by the weight of the aircraft?

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Elite 1K Joined: Jul 20, 2005 Posts: 1034 Status: Offline

Well in regards to the Sukhoi family being more maneuverable, I'd say the Raptor can do anything they can. The difference is that the F-22 can do it with total control while the Sukhoi's don't seem to retain much control.

The weight is from all the gold inside, why do you think it cost so much LMAO

Senior member Joined: Dec 14, 2006 Posts: 472

I still think the raptor has a higher thrust weight ratio and the lower wing loading then it's more primitive Soviet counterparts (Sukhoi).

The raptors weight seems to be more than what designers initially planned for, the increase in weight will lower the performance, however from what I understand it is still has a considerably higher thrust to weight ratio (and probably better wing loading) then it's more primitive Soviet counterparts (Sukhoi). That's probably part of the reason that the F-22 appears to be more maneuverable then it's more primitive Soviet counterparts (Sukhoi).

One would think that there would be some weight savings using more modern lighter compact electronics. However the capabilities/demands have been drastically increased. Also the redundancy has been vastly increased. In the early days if you had a failure you were SOL. Now days there is so much redundancy, that with most failures you can continue the mission, or be able to limp back home. Whereas in the past and electronic failure often resulted in scrubbing a mission and sometimes were catastrophic. The raptor has a lot of electronic redundancies, which allows most of the systems to cross check themselves and look for failures and to automatically compensate for failures and to disable the electronics that are in failure. From what I understand the electronics also seem to be layered in redundancy, such as if the main system needs to have a reboot, the more primitive electronics can likely keep the airplane flying while it's doing a reboot.

Enthusiast Joined: Oct 19, 2006 Posts: 88 Status: Offline

Tinito_16 wrote:

Hello to everyone,

I've noticed there seems to be alot of concern over the F-22's weight in some sectors of the defense community, because it is heavier than the F-15C it is replacing, and analysts have said that dogfighting capability may be diminished.

I assume that you are referring to some of the pronouncements made by Pierre Sprey and his fellow Boyd acolytes.

I have likwise been surprised by the curious focus on weight. I find it endlessly amusing that the remaining members of the original "Fighter Mafia" - and self-proclaimed inheritors of John Boyd's lightweight fighter legacy - appear to have flunked the basics of the same energy-maneuverability theory tha John Boyd pioneered.

Put simply, agility has nothing to do with weight, and everything to do with:
- thrust-to-weight ratio (or thrust loading)
- wing loading
- aerodynamic performance, and
- control authority

You can have a lightweight fighter, or a heavy fighter - it's the thrust-to-weight ratio and drag coefficient that will decide the acceleration rate, not the weight of the airplane.

Similarly, turn rate will be a function of several variables - but not of weight on its own. Weight always appears in association with wing loading or thrust loading - never alone.

The Raptor combines excellent thrust loading, low wing loading, superior aerodynamics, and unmatched control authority. Combine them all, and you have a dogfight platform without equal. Combine them with stealth, supercruise, and a new generation of sensor integration, and you have the most lethal air-to-air weapon ever envisioned.

I saw the video of when the YF-22 crashed in flight testing. I also saw pictures of the Raptor which crashed after takeoff. It seems the airframe is extremely strong, because the YF-22 didn't break up, it just slid, and the production Raptor which crashed was going to be rebuilt (according to the report I read). Is this strength related to the weight?

Elite 1K Joined: Aug 19, 2004 Posts: 1090

Tinito_16 wrote:

Is this strength related to the weight?

There is no direct relation. Weight is just that... weight. Or mass times the acceleration due to gravity near the surface of the earth if you prefer. Smile

Quote:

Or mass times the acceleration due to gravity near the surface of the earth if you prefer.

Oh, please don't traumatize me any more than I've already been by college physics Bang Head

Crew dog physics says put a big enough engine on a brick and it will fly Doh

Some pilots said the Raptor's thrust to weight is close to 1:1, slightly greater. I did the PUBLISHED numbers, and this seems to be bull. Anyone's take?

Senior member Joined: Dec 14, 2006 Posts: 472

The last I looked (a while back) the exact weight of the raptor was secret and subject to change. Often when congress cuts funding the weight goes down, so does capability. Often when they find funding (they add hardware, thusly capability) or have to strengthen parts to fix weaknesses, the weight and costs goes up.

I think most or all of the public listings of weight are estimates or ballpark figures. Wink

Elite 1K Joined: Aug 19, 2004 Posts: 1090

At sea level static conditions the F-22's T/W ratio is well above 1.0 with a full load of internal fuel/weapons. Even if you take the most conservative estimates for the F-22's weight with full internal fuel and weapons loadout, the T/W ratio at sea level static conditions is still over 1.0. And remember, installed thrust increases dramatically with airspeed at sea level. The thing probably has close to 80,000 lbs of total thrust at sea level and Mach 0.8 or so. I have no idea what the actual numbers are, but T/W ratio is likely never under 1.0 unless the F-22 is carrying two full external drop tanks. And when is it going to be in a combat situation with those things still hanging off the wings? Like... never.

Last but not least, acceleration is determined by (T-D)/W where D = total drag. Since the F-22 fights in a completely clean configuration, it doesn't have to worry about additional drag from weapons pylons and external stores. Any other operational fighter goes into combat with at least some additional drag from weapons and/or weapons pylons. Even if the stores are semi-recessed, there's still some additional drag. There are no "gun fighters" anymore. Last one of those was the F-8, no? And even that carried 4xAIM-9 externally. That's not exactly clean. Smile

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Raptor's Weight