F 100 P&W 229 vs. F 110 GE 129 - for and against

[ViperEnforcer]

One thing I'd be interested to know is whether F-15Es do better with F110-GE-129s as opposed to F100-PW-229s. I believe they have some GE powered Strike Eagles in service, but I could be wrong. You wouldn't happen to know, would you? The variable geometry inlet of the F-15 should do wonders when coupled to a F100-PW-229. I wonder if they can provide adequate mass flow to the F110-GE-129s under all conditions, however.

Raptor I've heard from an Eagle driver that during tests in the Strike Eagle the -129 offered better performance than the -229. Someone posted some data on this site a while back which showed that a GE equipped Strike Eagle will supercruise at a higher mach than its -229 counterpart, mach 1.08 vs mach 1.14.

HTH
Obi

This is correct. Back in 97, here at Edwards one of pre production Strike Eagles was fitted witha pair of GE-129. The Brit test Pilot who flew many of the test flights was highly impressed. The aircraft broke previous time to climb records. In fact, the jet went a little to fast, as the front canopy melted away from the upper front fame on one particualr speed run.

All test points were met and more often well exceeded that of the -229. The one problem it had was during taxing. With both GE-129s at idle, the jet would pick up too much speed while taxing, thus creating a hot brake situation. The simple fix at the time was just to taxi and run with one motor till EOR. Then the number two could be spun up and take off commense.

Mike V

[Obi_Offiah]

This is correct. Back in 97, here at Edwards one of pre production Strike Eagles was fitted witha pair of GE-129. The Brit test Pilot who flew many of the test flights was highly impressed. The aircraft broke previous time to climb records. In fact, the jet went a little to fast, as the front canopy melted away from the upper front fame on one particualr speed run.

All test points were met and more often well exceeded that of the -229. The one problem it had was during taxing. With both GE-129s at idle, the jet would pick up too much speed while taxing, thus creating a hot brake situation. The simple fix at the time was just to taxi and run with one motor till EOR. Then the number two could be spun up and take off commense.

Mike V

Thanks for the insight Mike.
South Korea are flying GE equipped Strike Eagles now, do you know if they use the taxi procedure you mentioned?

Obi

[ViperEnforcer]

From what the GE Tech Rep told me, the DEC(s) were programmed to run the idle at a lower intervals, so it did not crank out as must thrust.

There were also 2 Strikes Eagles fitted GE-129 pacer motors at Nellis till about 1999. I only saw one of them when TDY, during our NVIS testing.

Mike V

[EFTC]

I gotta go against the masses here, I feel the P&W is the better choice. I say that for one simple reason. And that is who has been buiding jet engines longer. I may be wrong but is stand by that, and that alone.

Actually, General Electric has been making jets longer than Pratt. The government chose GE to make the first U.S. jet engine because of its work with turbosuperchargers before and during WW2. GE's first engine was flown in 1942, while the first Pratt flew in 1948. Both were copies of British designs. Pratt's first original design was the J57 in 1952. GE's first original design was the J35, first flown in 1946.

[That_Engine_Guy]

Actually, General Electric has been making jets longer than Pratt. The government chose GE to make the first U.S. jet engine because of its work with turbosuperchargers before and during WW2. GE's first engine was flown in 1942, while the first Pratt flew in 1948. Both were copies of British designs. Pratt's first original design was the J57 in 1952. GE's first original design was the J35, first flown in 1946.

To clarify... (from the Centennial of Flight web site)

Pratt & Whitney had spent the war years focusing exclusively on its piston engines, and in 1945, was far behind its competitors in jet engine development. General Electric and also Westinghouse were already building turbojets. Pratt & Whitney began by first building jets of British design. But it realized that it would have to begin building its own jet engines. The company's first jet engine, the J42 Turbo-Wasp, was delivered to the Navy in November 1948 for installation in the Grumman F9F-2 Panther. A second jet engine, the J48, began production in 1950. Both these engines powered aircraft that served in the Korean War.

But...

Just six months after forming, (Pratt & Whitney) produced the successful Wasp engine, which included a number of important technical advances. Soon after it passed the Navy's qualification test in March 1926, the Navy ordered 200 engines. The Wasp exhibited speed, performance, climb, and reliability that contributed to America's leadership in world aviation.

So... P&W has been making aircraft engines much longer than GE, even if GE had a few years head start on the turbine market. The Army didn't want to bother P&W with turbine design and construction at the time as they were producing and designing piston engines used for WWII. In effect P&W got the shaft for doing such a great job on aircraft engines during WWII. GE also used "copies" of British engines at first. P&W was first at getting a "dual-spool axial-flow" design to produce more that 10,000lbs of thrust which allowed the J57 to be the first super sonic engine in level flight.

I'd say they caught up rather quickly...

[EFTC]

The Army didn't want to bother Pratt with building turbines simply because Pratt did not have experience with the technology (besides being overloaded during the war). Someone may correct me if I'm wrong, but I have never heard of Pratt being considered for the job. Westinghouse and GE were the natural choices because of their histories.

Pratt HAD to catch up or would be out of the game altogether. Their corporate leadership chose to invest millions of the company's own dollars into what became the J57 (you'll get no arguments from me on the virtues of that engine--well most of them anyway). But while Pratt was catching up with the J57, GE had already considered the two rotor approach and abandoned it in favor of the lighter and more stall resistant variable stator concept, which became the first mach 2 engine (J79). These two engines were about the most important advances in turbojet technology I can think of, but they are really like comparing apples to oranges.

[velos35]

I recently visited an f16 block 52+ (i fly block 50) squadron and when i watched the video tape of a recorded take off in a routine flight i noticed that the acceleration during take off is smaller than the f16 block 50.There is a difference you can tell.Besides that , pilots who have flown with both aircraft state that the performance of the Block 50 in acceleration , turn performance especially at low altitudes is better.

[SixerViper]

Has any one jet engine powered more different airplanes than the J-57? I can think of six different production airplanes that flew with this engine in one form or another.

[JetTest]

I have heard that the F15K's in SK are having augmentor no-lights at pretty much all points in the operational envelope, but troubleshooting has not yet identified the cause, but since the USAF never bought that configuration ROKAF is basically "on their own" with trying to correct it. ROKAF is currently shopping for more jets, and they are competeing the engine, maybe because of the problems they are having with the -129.

[That_Engine_Guy]

ROKAF is currently shopping for more jets, and they are competeing the engine, maybe because of the problems they are having with the -129.

I've also heard that they have talked about putting PW-229s into the Ks since they're having so many difficulties with the GE-129.

[JetTest]

Certainly an option under consideration.

[Robust]

Strange...Koreans are using PW-229 engines in their F-16s...and I have seen reports that they were not happy about PW-229 engines...I believe that it was one of the resons that they picked GE-129 when they purchased F-15Ks ...Now this news that Koreans are not happy with GE-129...Does not make any sense...Consider that Saudi Arabia is even switching from PW-229 to GE-129 by spending a lot money for their F-15Ss...What was wrong with Saudi PW engines that required switching to GE in F-15S?

Question...If there is some sort of technical problems with GE-129 engines, why do you think that ROKAF should be "one their own"? What does GE do to solve it? I am guessing they are still responable to support of their own product( probably part of their contract with GE). how did Korean purchase F-15Ks? FMS or Commercial?

[JetTest]

From what I have heard, GE has looked at the hardware and found no apparent cause, so it is still between GE, Boeing and ROKAF to try to solve it, as there is no USAF history or support for the configuration. Yes, in the past the ROKAF has complained about the -229, and I believe has the highest incident rate with it, worse than any other -229 operator, but it is interesting that PW delivered kits consisting of proprietary process and material parts to Samsung (maybe 30-40% of the engine) and the rest of the engine and all assembly was in Korea under a license, not by PW. Regardi Saudi, it will be interesting to wait a few years to see if they have similar complaints or issues with the -129, as they have a pretty demanding operational environment.

[That_Engine_Guy]

If I remember correctly, Korea was upset with PW after the crash of a PW-229 Viper. I believe the defect was traced back to turbine blades that were manufactured by a local Korean company who was not making the blades to "spec" The fault was limited to Korean PW-229s only, and did not affect the USAF or other FMS fleets. Since that incident the Koreans have had other mishaps caused by engine maintenance issues. Again this is not PW's fault but rather the operator's.

Korea tried to sue PW over the incident in International Court. Still blaming PW, they wanted the $20M+ to replace the aircraft. The FMS contracts and fine print kept Korea from recovering the cost of the aircraft from PW and they were quite upset. The F-15K was purchased with GE engines shortly after. (Lets not forget, ALL of Korea's Vipers are PW powered)

Now they have F-15Ks with the GE-129 and have some issues with the engines as installed in an Eagle. Even the PW-229 runs differently in an Eagle than a Viper. As mentioned before Korea is "on its own" as the USAF does not own GE powered Vipers, and has no technical or operational experience or involvement.

I'm not sure why the Saudis are going with some GE powered Eagles. That may be a political move, or a preference of the Saudi Royalty. I haven't heard of any issues the Saudis have had with the PW-229.

Thought: I don't believe GE supports their products as much as PW. I believe they are more of the "here it is, it's all yours now" type company. PW has more technical involvement with their products after the sale.

[asiatrails]

And the reason that the Saudi's are dumping the Pratt's out of the F-15's and replacing them with GE -129's is

Real World Performance and Reliability