F-35 and Airshows

Discuss the F-35 Lightning II
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by jetblast16 » 28 Jul 2018, 23:54

Agreed. Watching one of its climbs is very interesting..the pilot terminates the climb quickly. The jet had incredible momentum; trailing con sheets / streaks were coming from its TEs. Looked like a meteor. Very interesting...a lot of excess momentum. Just sayin' :wink:
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by F-16ADF » 28 Jul 2018, 23:56

I thought the same thing with the F-35 (as with F-22). USAF probably wants to keep everybody in the dark as far as the 22 and 35 real thrust and actual empty weights (22 has an overtly flimsy nose-wheel for supposedly being 43K and change........)????


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by jetblast16 » 29 Jul 2018, 00:01

Something doesn't seem to add up (at least to my non-aero engineer eyes / training)

The jet has a somewhat less than favorable inlet configuration (S-shaped to conceal the engine's fan from radar energy); the fuselage is very wide; it has a blunt nose; the wings are stubby; it supposedly weighs about 29k LBS empty and has a sea-level MAX AB thrust setting of 43k...and yet it can climb like a Raptor, at least in denser air for a time..
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by fbw » 29 Jul 2018, 00:31

sferrin wrote:
jetblast16 wrote:Watching the recent videos of the F-35A at RIAT is beginning to make me think that the jet has a bit more smash (thrust) than the Air Force is letting on



They always say 42k-43k but I've seen at least one source say 48k and P&W themselves have said it's been run at over 50k on the bench.


Doubtful. P&W has 43k on all specs I’ve seen. Besides that’s static uninstalled thrust. At or near sea level moving at a few hundred knots like at an air show, it’s very possible the aircraft is producing more than 43,000lbs.


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by sprstdlyscottsmn » 29 Jul 2018, 01:09

As a reference, the F110-GE-400 was uninstalled static rated at 24k and change. Installed at 0.9M at Sea Level it was pushing 30k.
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by gta4 » 29 Jul 2018, 03:10

jetblast16 wrote:Something doesn't seem to add up (at least to my non-aero engineer eyes / training)

The jet has a somewhat less than favorable inlet configuration (S-shaped to conceal the engine's fan from radar energy); the fuselage is very wide; it has a blunt nose; the wings are stubby; it supposedly weighs about 29k LBS empty and has a sea-level MAX AB thrust setting of 43k...and yet it can climb like a Raptor, at least in denser air for a time..


I don't think F-35's wings are stubby. It has a sweep of 30-35deg which is lowest among all 5th gen, and its aspect ratio is 2.7 which is also the highest among all 5th gen. All these contributes to lift curve slope and subsonic turns.


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by sferrin » 29 Jul 2018, 05:32

fbw wrote:
sferrin wrote:
jetblast16 wrote:Watching the recent videos of the F-35A at RIAT is beginning to make me think that the jet has a bit more smash (thrust) than the Air Force is letting on



They always say 42k-43k but I've seen at least one source say 48k and P&W themselves have said it's been run at over 50k on the bench.


Doubtful. P&W has 43k on all specs I’ve seen.


Apparently you know more than P&W themselves. :roll:

"Aerospace Daily & Defense Report
WEST PALM BEACH, Fla. — Pratt & Whitney is upping the ante in the ongoing F-35 Joint Strike Fighter engine war by revealing the F135 has achieved combat-rated thrust 20% higher than the specification. The disclosure raises the demonstrated sea-level thrust for the F135 above 50,000 lb., and follows results from the General Electric/Rolls-Royce Fighter Engine Team earlier this month that indicate the F136 alternate engine has in excess of 15% margin against the same ..."
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by wrightwing » 29 Jul 2018, 06:13

sferrin wrote:



They always say 42k-43k but I've seen at least one source say 48k and P&W themselves have said it's been run at over 50k on the bench.

Doubtful. P&W has 43k on all specs I’ve seen.

Apparently you know more than P&W themselves. :roll:

"Aerospace Daily & Defense Report
WEST PALM BEACH, Fla. — Pratt & Whitney is upping the ante in the ongoing F-35 Joint Strike Fighter engine war by revealing the F135 has achieved combat-rated thrust 20% higher than the specification. The disclosure raises the demonstrated sea-level thrust for the F135 above 50,000 lb., and follows results from the General Electric/Rolls-Royce Fighter Engine Team earlier this month that indicate the F136 alternate engine has in excess of 15% margin against the same ..."


Which makes things very interesting, when the next gen motors could be making 20% more thrust. That's already interesting, if the baseline is 43k. If it's 48k (or 50k+), performance will definitely be eye watering.


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by spazsinbad » 29 Jul 2018, 06:16

Here is the teaser (where's the firecat?).
Pratt Raises Stakes In JSF Engine Battle
26 Aug 2010 Guy Norris

"Pratt & Whitney is upping the ante in the ongoing F-35 Joint Strike Fighter engine war by revealing the F135 has achieved combat-rated thrust 20% higher than the specification. The disclosure raises the demonstrated sea-level thrust for the F135 above 50,000 lb., and follows results from the General Electric/Rolls-Royce Fighter Engine Team earlier this month that indicate the F136 alternate engine has in excess of 15% margin against the same specification. Pratt & Whitney…"

Source: http://aviationweek.com/awin/pratt-rais ... e-battle-0

As usual a good answer from 'TEG' re above: The significance of the F135 exceeding designed performance 22 Oct 2011
viewtopic.php?t=16265 [SCROLL DOWN FOR 'TEG']


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by fbw » 29 Jul 2018, 13:56

sferrin wrote:
fbw wrote:
sferrin wrote:They always say 42k-43k but I've seen at least one source say 48k and P&W themselves have said it's been run at over 50k on the bench.


Doubtful. P&W has 43k on all specs I’ve seen.


Apparently you know more than P&W themselves. :roll:

"Aerospace Daily & Defense Report
WEST PALM BEACH, Fla. — Pratt & Whitney is upping the ante in the ongoing F-35 Joint Strike Fighter engine war by revealing the F135 has achieved combat-rated thrust 20% higher than the specification. The disclosure raises the demonstrated sea-level thrust for the F135 above 50,000 lb., and follows results from the General Electric/Rolls-Royce Fighter Engine Team earlier this month that indicate the F136 alternate engine has in excess of 15% margin against the same ..."


Apparently you don’t know the difference between testing to demonstrate future thrust growth and the current engine thrust. Tell you what, look through the spec sheets, the recent AAIA papers and find one statement that the current thrust exceeds 43k. I’ll do the same, want to place a bet who has more information?

Think before posting an obnoxious reply.


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by sferrin » 29 Jul 2018, 14:01

fbw wrote:Apparently you don’t know the difference between testing to demonstrate future thrust growth and the current engine thrust. Tell you what, look through the spec sheets, the recent AAIA papers and find one statement that the current thrust exceeds 43k. I’ll do the same, want to place a bet who has more information?

Think before posting an obnoxious reply.


I have a better idea. How about you work on your reading comprehension before getting your panties in a wad?
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by quicksilver » 29 Jul 2018, 15:36

It (48K) was "...testing to demonstrate future thrust growth...".


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by elvis1 » 29 Jul 2018, 15:48

spazsinbad wrote:Here is the teaser (where's the firecat?).
Pratt Raises Stakes In JSF Engine Battle
26 Aug 2010 Guy Norris

"Pratt & Whitney is upping the ante in the ongoing F-35 Joint Strike Fighter engine war by revealing the F135 has achieved combat-rated thrust 20% higher than the specification. The disclosure raises the demonstrated sea-level thrust for the F135 above 50,000 lb., and follows results from the General Electric/Rolls-Royce Fighter Engine Team earlier this month that indicate the F136 alternate engine has in excess of 15% margin against the same specification. Pratt & Whitney…"

Source: http://aviationweek.com/awin/pratt-rais ... e-battle-0

As usual a good answer from 'TEG' re above: The significance of the F135 exceeding designed performance 22 Oct 2011
viewtopic.php?t=16265 [SCROLL DOWN FOR 'TEG']


Thank You spazsinbad (and TEG). The level of expertise on this forum is quite amazing.


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by mixelflick » 29 Jul 2018, 23:03

I'll second the notion that there's more going on in these displays than meets the eye. It's performance after such tight turns going into the vertical is absolutely astounding. Very reminiscent of the Raptor.

Pratt really out-did itself with the F-135. It's the exact opposite situation the Russians have with the SU-57, and really under-scores how important the engine is in a 5th gen platform.


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by element1loop » 30 Jul 2018, 03:39

Recently someone within another thread said words to the effect that compared to WVR energy-agile fighting, BVR was comparatively a button pressing process (that effectively de-emphasises the need for agility, acceleration, high P:W, etc.).

I've previously argued that greater thrust and agility is necessary to fully exploit 5th-gen tactics. The BVR agility requirement takes the form of rapid direction changes, and aspect presentation management at and after initual contact and ID phase, then the "Orient' in OODA, for an open-flight to have the raw performance to quickly flank while still optimally managing VLO aspect and multispectral, to attempt to obtain a tactically desirable MDF-driven launch aspect and radius to the target's vector, to minimise detection of your attack. Allowing for optimal 'D' and 'A', within OODA.

Then using raw performance to maintain chosen tactical relative positioning and VLO-standoff radius to all opponents within the near fight (including ground aspects).

I would say this requires at least as much agility and 'smash' as the WVR fight. You're using raw performance to establish and manage relative advantages, electing to ruthlessly IMPOSE VLO, thus stacking the relative odds.

One other point, this may not be emphasised much as yet, but if a 5th-gen is eventually targeted and fired at, at true BVR ranges, a big part of negating that missile attack is a very early launch detection when combined with a very early and continuous, precise missile-nav trajectory determination, combined with outstanding F-35 relative direction changing, altitude changes, re-acceleration(s), away from the previous targeted missile fly-to zone. Plus high sustained non-AB speed after the re-acceleration, with fine aspect control (powerful yaw control, and continuous AOA management input) with the ability for high AOA HOBS snapshots, whilst using rudders to still minimise your relative signature level. Thus breaking target-grade 'lock' (if we can still call it that) and continually complicating the missile-nav flyout, bleeding missile energy, exponentially dropping PK potential, snap counter-launching to force a go-defensive response, thus making targeting updates and missile tracking and re-engagements even more difficult or unlikely (and all before the F-35 uses its other electronic and CM options).

In my view this is what accounts for the raw performance emphasis we see demonstrated in both of LM's 5th-generation designs.

Eventually a competitor will emerge which can target and track a missile at an F-35, at substantial BVR radius, but the performance to defeat it is more or less already present. The EODAS updates, combined with GO2 engine, ensures superior BVR margin, initiative and tactics (as will a fighter optimised DIRCM).

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