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Enthusiast Joined: Nov 10, 2006 Posts: 37 Status: Offline

I think that a clean Block 30/50 with the GE engine or a centerlined F-16 can supercruise for a little.What do you think?

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Elite 1K Joined: Apr 26, 2004 Posts: 1215 Status: Offline

I know that at 48k and clean it is very close, but not sure it can quite do it. I remember at Shaw our guys would bring the 50's in from Ft Worth clean and they talked about it allot. Long way to go with a clean jet from Ft Worth to Shaw.

Purple

I believe the 52's would be the closest to supercruise because...the GE engines produce more thrust in burner but the pratt can produce more at intermediate than the GE so therefore that is why I believe. I still dislike Pratt engines. BLK30 all the way!

Elite 1K Joined: Aug 19, 2004 Posts: 1092

fireball wrote:

I believe the 52's would be the closest to supercruise because...the GE engines produce more thrust in burner but the pratt can produce more at intermediate than the GE so therefore that is why I believe. I still dislike Pratt engines. BLK30 all the way!

First off, this is wrong. The F110-GE-100 produces more thrust in MIL power than the F100-PW-220 and the F110-GE-129 more than the F100-PW-229.

Secondly, if by supercruise you mean flying faster than Mach 1.0 in level flight without using the afterburner, then all F-16 variants are cable of this in clean (or almost clean) configuration. This doesn't occur at 48,000 ft as someone suggested though. Think more like medium to medium-high altitudes. I doubt even a Block 60 could do Mach 1.0+ in MIL power at 48K ft.

well even the Block 60 has moderate mil thrust (19k uninstalled compared to 18K of GE or Pratt) compared to maximum thrust (32K compared to 29K). Maximum thrust is expected to grow to 35-36K for the Blk 60 but the mil rating will not likely change.

Elite 1K Joined: Aug 19, 2004 Posts: 1092

sprstdlyscottsmn wrote:

well even the Block 60 has moderate mil thrust (19k uninstalled compared to 18K of GE or Pratt) compared to maximum thrust (32K compared to 29K). Maximum thrust is expected to grow to 35-36K for the Blk 60 but the mil rating will not likely change.

You're quoting uninstalled, sea level static figures. The installed performance of the F-16 Block 60 with F110-GE-132 at the altitudes where F-16s can, in general, go above Mach 1.0 in MIL power will no doubt be higher than any other F-16 variant. Also, an increase in uninstalled MIL seal level static thrust of 1,000 lbs is not insignificant. Regardless, all F-16s had/have the ability to cruise just above the Mach in a clean or near-clean configuration within a certain altitude range (medium to medium-high altitudes). The more powerful the engines got, the wider this altitude range became. The actual increase in sustained supersonic flight without AB never went up by that much, however. We're talking only a few tenths of a Mach increase max. It's the MIL level flight performance envelope in general that was expanded with the addition of more powerful engines.

Raptor_One wrote:

fireball wrote:

I believe the 52's would be the closest to super-cruise because...the GE engines produce more thrust in burner but the Pratt can produce more at intermediate than the GE so therefore that is why I believe. I still dislike Pratt engines. BLK30 all the way!

First off, this is wrong. The F110-GE-100 produces more thrust in MIL power than the F100-PW-220 and the F110-GE-129 more than the F100-PW-229.

Do we have to restart the mass-flow versus exit-velocity debate again? Twisted Evil

I too have heard (and believe) the -229s are better at "MIL" than the -129s due to their basic operational theory. (PW's Heat/velocity vs GE's Mass-flow esp at lower/medium altitude) Should we mention again a small-mouth Viper has less drag than a large-mouth especially at higher MACH?

I agree most Viper variants will super-cruise (by the old definition of MACH 1) but I would think the newer PW variants w/-229s would have a slightly higher speed at MIL given a clean configuration.

Exclamation

Lets not forget the DOD changed the "super cruise" definition after the introduction of the Raptor to mean "MACH 1.5+ without afterburner" versus the pre-Raptor definition of "Supersonic without the use of afterburner." Hard to explain to a US Senator why you want $140M fighters that can "super-cruise" when your $20M "legacy" F-16s from 1982 will do the same thing!? Rolling Eyes

If we want to further split hairs in the thread, it is "augmentation" on a turbo-fan engine, not "afterburning" as in turbo-jet. (A small but signifiant fact due to the fresh air flow of the fan's bypass air.)

We meet again Raptor1.... My old engine principle foe... Cheers

Elite 1K Joined: Aug 19, 2004 Posts: 1092

TEG,

I'm not going to debate over whether the GE- or PW-powered F-16s are faster. I know that the GE-powered variants are, indeed, faster than their PW-counterparts. They also have better acceleration. This is true for all altitudes except when it comes to the F110-GE-100 at low altitude and high Mach. The F110-GE-129 addressed the shortcomings of the -100 in the lower-right part of the envelope. As for augmentation vs. afterburning, I don't care if there is some technical difference in the definitions. There's little difference in the calculation methods used for a mixed-flow, low-bypass afterburning turbofan versus an afterburning turbojet. I understand the differences when it comes to different types of engines. I understand what I mean by "afterburner" whether it applies to a turbojet or turbofan. I understand how to calculate the effect of the afterburner in a turbofan or turbojet. If I'm using some slightly wrong terminology, so be it. I'll take knowledge (on a mathematical/thermodynamical/physics-based level) of what's actually going on inside the engine throughout its various stages versus knowledge of proper engine terminology.

Enthusiast Joined: Jun 03, 2006 Posts: 54 Status: Offline

Well without giving all the specs on it, while I was stationed at Edwards we had a Block25/30 with a block50 motor in it. This just frequently did safety chase for the F-22. Had a few pilots say that they were able to "supercurise" with out AB. Even after shutdown we would look at the MACH guage in the cockpit and it would saw 1.2 1.3 1.1. Now that was all on his say, of course we had no idea if they were telling the truth. The jet doing the chase usually had a clean config or at least a centerline.

510Gh0st| wrote:

Well without giving all the specs on it, while I was stationed at Edwards we had a Block25/30 with a block50 motor in it.

So was it a PW or GE motor? If you had a BLK25 the GE wouldn't make much more thrust due to the small-mouth intake. If you put a -229 from a BLK52 into a BLK25 it would be a hot setup, as -229s will make 29K+ thrust with a small-mouth airframe. A BLK30 with a -129 from a BLK50 would be similar but the BLK30s weighed more than the 25s so you'd loose some performance there.

I've heard rumor of a BLK25 with a -229 used to chase "high-performance" test articles at Edwards. I believe it was a D model Viper.

Enthusiast Joined: Jun 03, 2006 Posts: 54 Status: Offline

knew I forgot somthing. It was a GE, it had a BIG mouth intake though, you have to understand being Edwards, alot of the jets there were modded, some heavily. My jet was a BLK30 with 50 Avionics and a PW -229E instead of a GE in it.

510Gh0st| wrote:

My jet was a BLK30 with 50 Avionics and a PW -229E instead of a GE in it.

F100-PW-229E? No such thing, you may be thinking -220E.

There is a F100-PW-220E which would be a -100 or -200 engine brought up to -220 "Equivalent" standards. Hence the letter "E" They made just as much power as the -220 at a lower cost. The USAF used kits to modify the older engines to the new standards versus buying completely new engines.

There isn't a way to convert the -220 up to the full -229 standards as most of the engine is much different.

Here is a quote from another post of mine:

That_Engine_Guy wrote:

Some other "lesser know" F100 engine sub-types...

F100-PW-220LE - A further upgrade with improved materials, better cooling and other features for extended life and reduced maintenance.

F100-PW-220P - A major upgrade of earlier engines to incorporate as much F100-PW-229 technology as possible, notably including the advanced fan, improved DEEC and new augmentor fuel management with further segmentation. Other designations for such engines are F100-PW-220+ and F100-PW-220E+.

F100-PW-220U - Unaugmented version, a key feature being a convoluted S-shape jetpipe terminating in a flat fishtail propulsive nozzle for minimal signature. Fully marinised, and fitted with simplified control system. This engine powers the Northrop Grumman X-47B UAV. It is widely regarded as the key stepping-stone to the first fully stealthy UAV engine.

F100-PW-232 - Originally known as the PW-229IPE+ (Increased Performance Engine), and then as the PW-229A, this ultimate version has been intensively developed to be "an increased-thrust, affordable and exportable engine for the F-15 and F-16". The main new feature is a redesigned fan based on F119 technology. This has a new first stage, with larger FOD-resistant blades (but solid, avoiding sensitive F119 technology) and wide-chord blisk second and third stages. This handles an increased air flow, further enhanced by eliminating the variable inlet guide vanes of previous F100 engines. The engine was intended to be a bolt-on retrofit for any F-15 or F-16, but the PW-232 requires a larger maximum air flow, as indicated by the figures below for Maximum T-O ratings. To keep overall engine length constant, the augmentor has been shortened, and according to sources the improved engine is designed for either an all-axis vectoring nozzle or an ejector nozzle with reduced IR signature. At one point in testing the PW-232 was tested to the 37,000 lb st thrust, but was "detuned" to allow higher times between overhaul. This engine seemed to fall from the spotlight after the F119 engine began to enter service.

F100-PW-232 (F-16 'standard inlet') 129.45 kN (29,100 lb st)
F100-PW-232 (F-16 'big mouth inlet') 142.0 kN (31,860 lb st)
F100-PW-232 (ideal inlet) 144.85 kN (32,500 lb st)

The airflow of the F-16's 'standard inlet' would restrict the PW-232 to about the same performance as the PW-229.

In August 2004 the USAF announced a far-reaching further programme, called the Engine-Life Management Program (ELMP) expected to run 2005 to 2030 and cost at least USD1 billion. This will provide a far-reaching upgrade to all the 2,700 F100 engines (including PW-229s) in USAF service. The most urgent part of it, timed for 2006 to 2011 and cost "over USD500 million", is intended to double the service life with a shop-visit interval of 6,000 flight cycles. A particular modification will be to replace the engine DEEC to remove dated electronics and improve diagnostic and health management capabilities.

All the PW-200 engines have been removed from service with the USAF. After BRAC and PW-220E upgrade kit installations, all the remaining PW-100s of the F-15s will also be upgraded or replaced by engines removed from the retired F-16 fleet as it enters AMARC.

ANG Block 42 aircraft (Tulsa/Toledo) continue converting their aircraft from PW-220s to new production PW-229s. These PW-220 engines are also being sent to ANG F-15 units for use in place of the 30+ year old PW-100s.

Newbie Joined: Jan 28, 2007 Posts: 8 Status: Offline

There is a very short, non GEEK answer to your question. The answer is yes, an F-16 can supercruise all day long. Block 50's, that is. Mach 1 without afterburners is completly irrelevant however, because there is nothing magical about breaking the sound barrier, with or without augmentation. If you can cruise at .9 mach without augmentation, going 1.0 isn't really any different.

Elite 1K Joined: Aug 19, 2004 Posts: 1092

fasurp23 wrote:

There is a very short, non GEEK answer to your question. The answer is yes, an F-16 can supercruise all day long. Block 50's, that is. Mach 1 without afterburners is completly irrelevant however, because there is nothing magical about breaking the sound barrier, with or without augmentation. If you can cruise at .9 mach without augmentation, going 1.0 isn't really any different.

Ummmm.... maybe your answer is non-GEEK, but it's also non-right. See... geeks actually know stuff.

fasurp23 wrote:

because there is nothing magical about breaking the sound barrier, with or without augmentation. If you can cruise at .9 mach without augmentation, going 1.0 isn't really any different.

Tell that to NACA back about 60 years ago... Rolling Eyes

Perhaps the test pilots trying to break the sound barrier that died trying; or the fighter pilots of WWII who couldn't control their aircraft in high-speed dives and died would have found this information handy? Rolling Eyes

Supersonic flight is VERY different than sub-sonic flight. Trans-sonic flight is even more screwed up as the rules change over each individual section of the aircraft. (Some over MACH some under...)

We won't mention the actual shock wave the aircraft needs to pass through either. I'm sure all that extra drag (which requires extra thrust to penetrate) isn't important...

Exclamation

Early supersonic fighters could only maintain MACH1 with use of afterburners for the extra thrust required. Newer fighters could 'maintain' supersonic flight after pushing through MACH 1 with their burners on, then retarding the throttle to MIL. The latest fighters have enough power to simply push through MACH without touching burner.

Simple answer: YES most Vipers would be able to "super cruise" given the right conditions and no external stores.

Idea

Side note: All air being fed into a jet engine must be subsonic for the engine to operate. The blades of the engine suffer the same "compressibility" issues as a propeller when supersonic airflow hits them. All intakes must slow the air below MACH prior to it hitting the face of the engine or it will stall and flame-out...

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Can the F-16 supercruise?