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Officially, it is 35,000 lbs with no mention of the static dry thrust. There has also been ATF folks making the comment that the engine capable of roughly 3/4 of its maximum thrust w/o afterburner compared to 2/3 typical of most fighter turbofans. This, and that the dynamic thrust at supersonic speeds is very good compared to previous jets. All in all the available information is very vague.

Does anyone have a good estimate as to the actual performance of the engine? Or does anyone care to make an educated guess?

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Nope.... Some things better left un-told. Whistle

Needless to say it is alot.

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

dwightlooi wrote:

Officially, it is 35,000 lbs with no mention of the static dry thrust. There has also been ATF folks making the comment that the engine capable of roughly 3/4 of its maximum thrust w/o afterburner compared to 2/3 typical of most fighter turbofans. This, and that the dynamic thrust at supersonic speeds is very good compared to previous jets. All in all the available information is very vague.

Does anyone have a good estimate as to the actual performance of the engine? Or does anyone care to make an educated guess?

You could attempt to write your own engine simulation and make an educated guess as to the F-22's inlet pressure recovery performance throughout it's flight envelope. Of course you'd have to make a bunch of guesses about the F119-PW-100's component performance variables too. Anyway, you could probably make fairly educated guesses on all counts and crunch the numbers in an engine simulation, giving you approximate installed thrust of the F-22. Of course when you use so many educated guesses in the same overall calculation, the accuracy of the simulation isn't very good. The only other way to deduce installed thrust is via knowledge of the aircraft's aerodynamic coefficients throughout the envelope combined with its raw flight performance (excess power, flight envelope, level acceleration, etc.).

Specifics on engine performance are generally much harder to come by in my experience... even for relatively old, outdated models. If you have access to AIAA's Journal of Aircraft and/or Journal of Propulsion and Power, you might try skimming through the last 5-10 years of back issues. There's gotta be something in there by now about the F119 and/or F-22. This kind of information is very hard to find in the public domain for aircraft no longer in service though. Good luck finding solid info on the F-22 which just entered service.

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

Its been mentioned that the Raptor on dry thrust is damn near performing like an Eagle in burner. I'll post a link as soon as I find it again for you.

Enthusiast Joined: Nov 23, 2006 Posts: 28 Status: Offline

FWIW, Sweetman puts the max augmented thrust at 39,000lbs a pop and about 26,000lbs dry. If it's really cranking out 39K and the dry thrust is really close to 3/4ths, then it's dry thrust might be about 29K. Seems a little high but you never know.

BDF

F-16.net Editor Joined: Sep 23, 2003 Posts: 2850

Thrust.... at what altitude ? Laughing

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

Thats a good point Elp...maximum thrust certainly is not acheived on the ground or even at low airspeed.

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

elp wrote:

Thrust.... at what altitude ? Laughing

I think that's what Dwightlooi was wondering about. Hence his comment about dynamic thrust (i.e. thrust as a function of airspeed and altitude). Obviously it's not a trivial matter to estimate installed thrust at all airspeeds and altitudes an aircraft might fly at. Smile

Enthusiast Joined: Sep 27, 2006 Posts: 67 Status: Offline

Raptor_One wrote:

elp wrote:

Thrust.... at what altitude ? Laughing

I think that's what Dwightlooi was wondering about. Hence his comment about dynamic thrust (i.e. thrust as a function of airspeed and altitude). Obviously it's not a trivial matter to estimate installed thrust at all airspeeds and altitudes an aircraft might fly at. Smile

One thing is for certain; The PW F119 engines are monsters.... Cool

Enthusiast Joined: Sep 27, 2006 Posts: 67 Status: Offline

BDF wrote:

FWIW, Sweetman puts the max augmented thrust at 39,000lbs a pop and about 26,000lbs dry. If it's really cranking out 39K and the dry thrust is really close to 3/4ths, then it's dry thrust might be about 29K. Seems a little high but you never know.

BDF

That sounds about right... officially the F135 engines are 40,000 lbs on reheat, but there have been documents suggesting more like 43,000/28,000 for thrust, and those use the F119 core afaik.

Elite 1K Joined: Jul 22, 2005 Posts: 1012 Status: Offline

Neotopia wrote:

BDF wrote:

FWIW, Sweetman puts the max augmented thrust at 39,000lbs a pop and about 26,000lbs dry. If it's really cranking out 39K and the dry thrust is really close to 3/4ths, then it's dry thrust might be about 29K. Seems a little high but you never know.

BDF

That sounds about right... officially the F135 engines are 40,000 lbs on reheat, but there have been documents suggesting more like 43,000/28,000 for thrust, and those use the F119 core afaik.

I know I've mentioned it at least once here but as for the potential of the F135 the one in Boeing's X-32 was good for 34,000 dry and 52,000 in afterburner. Don't believe it? Consider that the X-32's takoff weight was roughly 34,000lbs and it wasn't using an afterburner for VTOL.

Enthusiast Joined: Mar 13, 2007 Posts: 98 Status: Offline

dwightlooi wrote:

Officially, it is 35,000 lbs with no mention of the static dry thrust. There has also been ATF folks making the comment that the engine capable of roughly 3/4 of its maximum thrust w/o afterburner compared to 2/3 typical of most fighter turbofans. This, and that the dynamic thrust at supersonic speeds is very good compared to previous jets. All in all the available information is very vague.

Does anyone have a good estimate as to the actual performance of the engine? Or does anyone care to make an educated guess?

Ain't no one who knows going to spill the beans on this. Let's look at the car analogy: throw a GM 3.6L on a dyno by itelf and its going to throw down (for arguments sake) 250hp at the crank (corrected for pressure/temp). Put it into a car and the dynamics of the tranny, exhaust, and intake all come into play. Throw a PW on a static test rig at sea level and it may pump out (for arguments sake) 35K pounds of thrust. Put it onto an airplane and your numbers are going to change. I believe that they found the intake design on the F-35 actually boosts the predicted thrust by something like 3000 pounds of thrust.... A good inlet design is critical to developing power much like on a car which is why the import rice tuner crowd, the first thing they do when modifying their cars is go straight to getting rid of the stock intake.

35,000 pounds of thrust is the number that is given to the public... Let's say the engine is at minimum capable of of pumping out that much thrust. I'm sure that given the conditions for it, the true thrust is higher than publicly stated (along with the 1.7 mach cruise speed), but is going to be less that 2x the original thrust ratings on the F-15A PW. Take off the restrictions of the plane as if we were in a time of war, and I'm sure that the 22 will cruise around all day at damned near the Eagles 2.5 top end speed... Of course you pay the penalties of heat damage to the airframe, but in time of war all that crap flies out the window. The 22 is the ultimate in sleeper looking airplanes: looks like a legacy plane, but has the performance of a mini-71.
The real shame is that we're getting only special forces types of quantities with the plane. With enough of those planes, it would totally completely irrelevant for the USN and USMC to have a lightly armed slow poke "stealthy" airplanes for pinprick strike missions; those two services could live quite happily with the superbug and never have to worry about going after heavily defended targets with a partially stealthy and slow/low flying airplane since the the 22 can handle those types of missions with much more ease.

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

fox100 wrote:

Of course you pay the penalties of heat damage to the airframe, but in time of war all that crap flies out the window.

It most certainly does not.

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

I'm quite sure that the F-35's installed thrust for sea level static conditions is not greater than the F135's uninstalled sea level static thrust. When a bare engine is tested, an "ideal" inlet is rigged up to give the engine maximum possible performance at static conditions. When you install the engine in an aircraft with a "fighter-type" inlet design, static thrust is going to be less than uninstalled performance. Once you get the aircraft moving fast enough however, installed thrust will eventually increase beyond the engine's uninstalled static thrust rating. This is true for just about any "fighter-like" inlet design. The F-16, for example, puts out well over 30,000 lbs of installed thrust above Mach 1.0... even the original F-16A with F100-PW-200 engine.

Raptor_One wrote:

I'm quite sure that the F-35's installed thrust for sea level static conditions is not greater than the F135's uninstalled sea level static thrust. When a bare engine is tested, an "ideal" inlet is rigged up to give the engine maximum possible performance at static conditions. When you install the engine in an aircraft with a "fighter-type" inlet design, static thrust is going to be less than uninstalled performance. Once you get the aircraft moving fast enough however, installed thrust will eventually increase beyond the engine's uninstalled static thrust rating. This is true for just about any "fighter-like" inlet design. The F-16, for example, puts out well over 30,000 lbs of installed thrust above Mach 1.0... even the original F-16A with F100-PW-200 engine.

Yeah, except that all the "specifications" on engine thrust we will come across are going to be static and uninstalled. This is true regardless of whether you are talking about the F414 (22,000 lbs), EJ200 (@20,250 lbs), F135 (43,000 lbs), F110-GE129 (29,400 lbs), or whatever. In otherwords, the F135 was listed as 43,000 lbs by Pratt & Whitney under the same standards which other engines have been listed -- idealized and all. The reason is that if you start talking about intake losses, dynamic gains, altitude losses, ambient temperature effects, AoA effects, etc then you no longer have "a number". In fact, you don't even have "a graph". What you have is dozens of graphs each holding all but two variables constant. You wouldn't ever find that on a one line "specification" on an engine's thrust rating.

What I was trying to get some inputs on is whether the 35,000 lbs "uninstalled", "static" and "idealized" thrust rating publicly given of the F119 is realistic or notably understated. And, more importantly, what is a realistic dry thrust rating of the engine -- there is NO official info whatsoever on that understated, unrealistic or otherwise. What we do know is that the F119 and F135 cores (which are supposed to be very similar) certainly have a lot of excess capacity for their stated maximum thrust ratings. Remember, the F135 core is capable of supporting (through a clutch, gearbox, additional fan, roll post tap offs, hindering vanes, 90 degree nozzle, and all that with their increased mechanical drag among other things) 39,400 lbs of dry thrust. Now, airflow restrictions and smaller diameter fan stages are restricting, but the core itself should have plenty of "horsepower" to spare.

For OFFICIAL F135 specifications from P&W look under "PrattWhintneyF135FactSheet060707.pdf"

http://www.lockheedmartin.com/data/assets/13640.zip

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Realistic thrust figures for the F119