The F100 is the safest single-engine fighter jet engine on record. US Air Force‘s F100-PW-220 and 229 powered F-16s have the lowest cumulative engine-related loss of aircraft (ERLOA) rate for any engine in its class. The most advanced model F100, the F100-PW-229, has recorded zero ERLOA in 14 years of service with the U.S. Air Force.

The F100 is the safest single-engine fighter jet engine on record. US Air Force‘s F100-PW-220 and 229 powered F-16s have the lowest cumulative engine-related loss of aircraft (ERLOA) rate for any engine in its class. The most advanced model F100, the F100-PW-229, has recorded zero ERLOA in 14 years of service with the U.S. Air Force.

The F119 is said to have a BPR of 0.30

Captain Mike Trujillo gives a thrust rating of ~35,000 lbf each for the F119s in the F-22.

http://news.bbc.co.uk/2/hi/uk_news/7502739.stm

Just to split a hair or two...

The airflow lbs/sec of the PW-229 is 254. The GE-129 is 270. The "big mouth" inlet was needed by the GEs to get optimal airflow for THEIR engine.

The PW-229 is happy with the same supply as it's PW-200 and PW-220 predecessors. (It just runs hotter/faster) It was designed this way so that ANY older F-16 would benefit from the upgrade to the PW-229. To upgrade an older block Viper (small mouth) with a GE-129, one would need to change the inlet as well to get the quoted maximum performance from the engine.

The PW-229 has also been called a "leaky turbojet" before the F119. The PW-229's BPR is 0.36 as opposed to the GE-129's BPR of 0.76. The origional GE F404 had a BPR of 0.34, newer models of the F404 have dropped to 0.27. The GE 414 of the E/F Hornet on the other-hand has increased it's BPR to 0.40.

The F119 is said to have a BPR of 0.30, while the F135's BPR was increased to 0.60 to gain economy needed by a single engine fighter. The increased BPR eliminates the "super cruise" performance of the F119 as it was not a requirement of the JSF (F-35 Lightening) program.

The bypass ratio of the F119 is believed to be 0.20:1. That of the F-135 is 0.56:1 or 0.57:1 depending on whether it is the STOVL or CTOL version.

If the F-35 does not supercruise, and that is a big IF, it will not be because of the bypass ratio. The exhaust velocity of a 0.57:1 engine and that of a 0.20:1 engine does not differ that much especially when you throw in the effects of a variable nozzle. Even a 2.0:1 bypass engine is capable of supporting Mach 1.5 cruise given the right aerodynamics and P/W ratio. F-16s can do about 1.2 clean and EFs can reach about 1.3~1.4 with no weapons or minimal stores. This is despite a 0.76:1 and 0.4:1 bypass respectively. Several Mach 1.5 business jet proposals specify the old JT8D-200 series engine with a whopping 2.0:1 bypass. The M88-2 on the Rafale has a 0.25:1 ratio and it barely supercruises just like the late model sixteens.

If the F-35 does not supercruise it'll be a combination of drag and a lower T/W ratio compared to the F-22. However, in general, being about 2/3 the weight, 75% the frontal area and with about 60% the thrust it doesn't general work out to half the cruise performance. Which is why I suspect that the F-35A should be able to sustain cruise in the Mach 1.2~1.4 range -- somewhere between that of the F-16C and the Typhoon. But... that remains to be seen. When the USAF talks about supercruise they are not talking about going Mach 1.1 which does little vs going at 0.95. They are talking about the ability to go Mach 1.7 -- the typical Vmax using afterburners with 4th generation types when you are carrying pylons and tactically useful stores. The F-35A will not do that. But it should fly as fast as clean sixteens and Rafales with internal weapons.

Going from a 0.20:1 bypass F119 to a 0.57:1 ratio in the F135 is a practical matter of wanting to keep the same core while requiring extra thrust. The F135 is basically an uprated F119 with the core mated to a new fan and Low Pressure Turbine. This is the fastest and least developmentally risky way of getting extra thrust. The alternative will be to increase the size of the core which will require an all new design.

I'm hoping the F135 shares in the success the F119 and the F100-PW-229 have had since introduction. They are both VERY safe engines.

Keep 'em flyin'
TEG

Not really...The bypass ratio of the F119 is believed to be 0.20:1. That of the F-135 is 0.56:1 or 0.57:1 depending on whether it is the STOVL or CTOL version.

If the F-35 does not supercruise, and that is a big IF, it will not be because of the bypass ratio.

Does the F-35 supercruise?
No, neither the F135 or F136 engines were designed to supercruise.

The exhaust velocity of a 0.57:1 engine and that of a 0.20:1 engine does not differ that much especially when you throw in the effects of a variable nozzle. Even a 2.0:1 bypass engine is capable of supporting Mach 1.5 cruise given the right aerodynamics and P/W ratio.

F-16s can do about 1.2 clean and EFs can reach about 1.3~1.4 with no weapons or minimal stores. This is despite a 0.76:1 and 0.4:1 bypass respectively. Several Mach 1.5 business jet proposals specify the old JT8D-200 series engine with a whopping 2.0:1 bypass. The M88-2 on the Rafale has a 0.25:1 ratio and it barely supercruises just like the late model sixteens.

If the F-35 does not supercruise it'll be a combination of drag and a lower T/W ratio compared to the F-22. However, in general, being about 2/3 the weight, 75% the frontal area and with about 60% the thrust it doesn't general work out to half the cruise performance. Which is why I suspect that the F-35A should be able to sustain cruise in the Mach 1.2~1.4 range -- somewhere between that of the F-16C and the Typhoon. But... that remains to be seen. When the USAF talks about supercruise they are not talking about going Mach 1.1 which does little vs going at 0.95. They are talking about the ability to go Mach 1.7 -- the typical Vmax using afterburners with 4th generation types when you are carrying pylons and tactically useful stores. The F-35A will not do that. But it should fly as fast as clean sixteens and Rafales with internal weapons.

Going from a 0.20:1 bypass F119 to a 0.57:1 ratio in the F135 is a practical matter of wanting to keep the same core while requiring extra thrust. The F135 is basically an uprated F119 with the core mated to a new fan and Low Pressure Turbine. This is the fastest and least developmentally risky way of getting extra thrust. The alternative will be to increase the size of the core which will require an all new design.

You don't think increasing the engine's bypass air from 20% to 60% wouldn't make that much difference without afterburner? I doubt the remaining flow will be able to make enough average exhaust velocity from the nozzle to provide the same amount of thrust at MACH speeds as the former BPR. Let's also remember the F135 has a larger low-pressure turbine to drive that fan and will extract more energy from the core exhaust stream, further reducing it's velocity/thrust. If the extra turbine wasn't needed to help drive the fan of the -100 or -400 variants it wouldnt' have beein included.

In the F119 (assuming 0.20:1), about 16.7% of the intake air goes around the core. In an F135 (assuming 0.57:1) about 36.3% of it goes around the core. You extract more energy from the exhaust to drive about twice as much bypass flow, but that three stage fan also moves and pressurizes the air it moves. Assuming that the engine can work efficiently with increased back pressure, narrowing the exhaust nozzle area will add velocity to the exhaust stream.

There is also a misconception that exhaust velocity is required to make thrust at Mach speeds. This is not true. A baseball shot out the rear at 100km/h makes the same amount of thrust at Mach 3 as it does at standstill! The issue of exhaust velocity comes from the fact that if you move a lot of air at low speeds your intakes have to be much bigger than if you move a lot less air at extremely high speeds. Larger intakes means increased drag for the aircraft. Every bit of drag from that intake, counts against the net thrust that you have. Hence, if you want to go fast efficiently at high Machs it helps if you need to ingest as little air as possible and make the most use of what you do ingest by accelerating it to as high a speed as you can.

If you look at the combined area of the two intakes on the F-35 and compare them to that of that of one of the F-22's intakes they are about 25% larger. That is the penalty in drag. However, the engine also makes more about 16% more thrust. So the actual net thrust fall off at say Mach 1.7 due to the bypass ratio is less than 10%. Further more, the F-35 is not going to go Mach 1.7 even if it had an F119 BP class engine of the same thrust as the F135. More likely, it is going to go, say, Mach 1.3 +-0.1. At that speed the gains and losses due to bypass is even less tangible.

True. MACH flight, (not Raptor/F119 style "Supercruise) without burner does have more to do with thrust/speed/drag and exit velocity. We're going by the USAF/DoD definition of "Supercruise" which they've seem to have adjusted to MACH 1.5 for specific procurement reasons; like you said further down. Like I said though, the F135 wasn't "designed" for Supercruise, it was built for better economy. (Low-Risk, Single engine performance, lower SFC, simpler nozzle, size/weight, etc)

I think that it was designed as an updated F119 with a bigger fan mainly because they already had the F119 core and bolting a bigger fan to it is the cheapest, fastest and least risky way of getting another 10~20% more thrust for the F-35. The issue of bypass ratio related performance loss at F-22 cruise speeds probably never came up because it is a non-issue given that the F-35 is not going to cruise at Mach 1.7. At the maximum plausible cruise speed for the F-35 of let's say Mach 1.4 (I doubt it but it is within the outer bounds of what may be), it the 0.57:1 may in fact be more optimal. It doesn't mean that an F135 powered aircraft -- given appropriate aerodynamics and other considerations -- cannot cruise at Mach 1.7. It just means that the engine may lose a little more of its rated thrust at that speed than the F119 does.

I agree, but I still doubt the F-35 will be able to "Supercruse" at the same MACH number as an F-22 in a combined formation.

Agreed. I have said that the F-35 WILL NOT supercruise at Mach 1.7 or even 1.5. But I believe that there is a good chance that it'll do Mach 1.2~1.3 which is quite competitive with various 4th generation types which advertise themselves as supercruisers. This also meets the textbook definition of "Supercruise" taken to mean going faster than Mach 1 on dry power, which is why I said that there is a good chance that the F-35A will supercruise (albeit not to USAF standards).

He said "about" 35,000 lbs. per motor, while Moga directly and specifically stated 37,000 lbs. per. One is a statement of class (35,000 lbs. class), the other a more specific figure, which Moga would not have pulled out of thin air. It's like saying someone is in his mid-30s, as opposed to saying someone is 37 years-old.