F-35 got 0 losses in dogfights against F-15E Red Air

The F-35 compared with other modern jets.
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by mixelflick » 30 Jun 2016, 13:15

basher54321 wrote:
hornetfinn wrote:AFAIK, F-15C is a 9 G airframe, but F-15A had been restricted to that 7.33 G. AFAIK, F-15A was also basically a 9 G airframe, but there were some conditions where it was restricted to 7.33 and because there was no overload measurement/warning system in A/B-models it was always restricted to that 7.33 G. In C/D-models such a system was installed and they are capable of 9G unless of course there were restricting factors. Someone please correct if that's wrong!


Both C and E have 9G structural limits in manuals. The E structure was beefed up - being heavier it needs to and can pull 9G at heavier weights than the C.


There's a dogfight of desert storm documentary where an F-15 driver says he pulled 12g's. I tend to believe him. He said the Eagle is a strong bird and both he and the airframe held up just fine.

Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..


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by basher54321 » 30 Jun 2016, 13:22

mixelflick wrote:
There's a dogfight of desert storm documentary where an F-15 driver says he pulled 12g's. I tend to believe him. He said the Eagle is a strong bird and both he and the airframe held up just fine.

Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..



Probably true - plenty of old jets (Mirage III etc) did in combat and some pilots lived to tell the tail. That's what happens when you don't have limiters - he has snatched back on the stick and probably over stressed the airframe and has put himself in danger of blacking out - all when there was no need to do that whatsoever in that situation.


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by spazsinbad » 30 Jun 2016, 14:33

IF youse seen this before stop reading NOW.
F-35A Nearly Combat Ready
27 Jun 2016 Public Affairs Release

"...Hill’s F-35A pilots flew large-force exercises with F-15Es from Mountain Home’s 366th Fighter Wing and remained
undefeated during air-to-air engagements against red air, or “enemy” aircraft...."

Source: http://www.jsf.mil/news/docs/20160627_F ... _Ready.pdf (115Kb)


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by sferrin » 30 Jun 2016, 14:49

mixelflick wrote:
basher54321 wrote:
hornetfinn wrote:AFAIK, F-15C is a 9 G airframe, but F-15A had been restricted to that 7.33 G. AFAIK, F-15A was also basically a 9 G airframe, but there were some conditions where it was restricted to 7.33 and because there was no overload measurement/warning system in A/B-models it was always restricted to that 7.33 G. In C/D-models such a system was installed and they are capable of 9G unless of course there were restricting factors. Someone please correct if that's wrong!


Both C and E have 9G structural limits in manuals. The E structure was beefed up - being heavier it needs to and can pull 9G at heavier weights than the C.


There's a dogfight of desert storm documentary where an F-15 driver says he pulled 12g's. I tend to believe him. He said the Eagle is a strong bird and both he and the airframe held up just fine.

Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..


Lots of stuff happens that doesn't necessarily make the papers. Read of a F4D Skyray pulling 12Gs once and wrinkling a wing but got back on the ground. Read of an F-14A Tomcat pulling 11 NEGATIVE Gs in an inverted, out-of-control dive which they eventually recovered from (the pilot apparently breaking the grip off the stick in the process).
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by Dragon029 » 30 Jun 2016, 17:00

mixelflick wrote:Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..

Most aircraft are capable of being pulled to around 1.5x their G rating; I've heard that jets that pull those sorts of manoeuvres tend to be immediately retired after landing though; by going so far beyond their design load, you can't accurately predict the damage that's been caused and so you have to essentially tear the plane apart to inspect it thoroughly enough, at which point it's then easier to cannibalise the parts than rebuild the jet.


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by XanderCrews » 30 Jun 2016, 17:11

Dragon029 wrote:
mixelflick wrote:Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..

Most aircraft are capable of being pulled to around 1.5x their G rating; I've heard that jets that pull those sorts of manoeuvres tend to be immediately retired after landing though; by going so far beyond their design load, you can't accurately predict the damage that's been caused and so you have to essentially tear the plane apart to inspect it thoroughly enough, at which point it's then easier to cannibalise the parts than rebuild the jet.



True.

You can exceed the G limits, but it may be the last flight ever. "every ship can be a minesweeper once"
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by structuresguy » 30 Jun 2016, 17:52

mixelflick wrote:There's a dogfight of desert storm documentary where an F-15 driver says he pulled 12g's. I tend to believe him. He said the Eagle is a strong bird and both he and the airframe held up just fine.

Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..



If it doesn't snap in half doesn't mean it held up just fine. Pilots that don't fix the jets have no pony in the race. :bang:


Dragon029 wrote:Most aircraft are capable of being pulled to around 1.5x their G rating; I've heard that jets that pull those sorts of manoeuvres tend to be immediately retired after landing though; by going so far beyond their design load, you can't accurately predict the damage that's been caused and so you have to essentially tear the plane apart to inspect it thoroughly enough, at which point it's then easier to cannibalise the parts than rebuild the jet.


Depends on the circumstances but yes an over G-inspections is extremely time consuming. We all love TAC DEMO's but as a structures guy that has worked East Coast F-15C demo jets the damage can be extensive. Once listen to
Maj. "Bondo" Costello laugh about how he had the over-G warning blairing at him for a solid 12 seconds. Sure was glad he thought it was funny.


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by XanderCrews » 30 Jun 2016, 18:04

structuresguy wrote:
mixelflick wrote:There's a dogfight of desert storm documentary where an F-15 driver says he pulled 12g's. I tend to believe him. He said the Eagle is a strong bird and both he and the airframe held up just fine.

Probably not something you'd want to do very often, but... what do you guys think? Truth or over-statement?? I also tend to think the F-35 can be over-ridden if necessary..



If it doesn't snap in half doesn't mean it held up just fine. Pilots that don't fix the jets have no pony in the race. :bang:


Dragon029 wrote:Most aircraft are capable of being pulled to around 1.5x their G rating; I've heard that jets that pull those sorts of manoeuvres tend to be immediately retired after landing though; by going so far beyond their design load, you can't accurately predict the damage that's been caused and so you have to essentially tear the plane apart to inspect it thoroughly enough, at which point it's then easier to cannibalise the parts than rebuild the jet.


Depends on the circumstances but yes an over G-inspections is extremely time consuming. We all love TAC DEMO's but as a structures guy that has worked East Coast F-15C demo jets the damage can be extensive. Once listen to
Maj. "Bondo" Costello laugh about how he had the over-G warning blairing at him for a solid 12 seconds. Sure was glad he thought it was funny.


My heart goes out to you, seriously.

Also: https://youtu.be/SdSj0_Fd4ds
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by 35_aoa » 01 Jul 2016, 07:12

basher54321 wrote:Probably true - plenty of old jets (Mirage III etc) did in combat and some pilots lived to tell the tail. That's what happens when you don't have limiters - he has snatched back on the stick and probably over stressed the airframe and has put himself in danger of blacking out - all when there was no need to do that whatsoever in that situation.


Even with limiters, you can still overstress if you aren't careful. Like you mentioned, "snatching" back on the stick, normally the biggest issue at lower gross weight/fuel state, you can beat the limiter. Very possible in even modern fighter aircraft…..ask me how I know. Can't speak to the F-15, though I'd imagine Mac Air didn't deviate much in the Hornet…….for us, we have a code that will pop. Depending on how severe the overstress was, combined with that code, will determine if it is a level I or level II event. Level I is a simple visual inspection, and most of the time, an overstress falls under this category. Level II is a full inspection where panels come off and the jet is down for a while. One quick 12G spike on a 9G airframe is probably not breaking the jet permanently, though it may well break every capillary in the pilot's skin. Stress fractures *normally* take many years and lots of overstress events to occur. It's a real thing in old jets that have been ridden hard, but is almost never a one time event, though a sustained 1.5x load limit pull would certainly break a lot of stuff and down a jet for a longer time, if not for good. That's just dumb flying in a training or demonstration setting.


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by basher54321 » 01 Jul 2016, 14:27

Thanks 35 - What G is a level II overstress at?

I was going from this because I was fairly certain you wont be getting anywhere near 12G in symmetric pitch -

viewtopic.php?f=22&t=24886&p=266875#p266875
The F-16 g limiter is not perfect and it can be defeated by a small amount, maybe .6 to .8 g. There is no way it would let you go to 11.2g in a turn. However there are two factors which may have led him to believe he did. First, his g meter is in the HUD and is driven by an accelerometer in the HUD electronics. The flight control accelerometer is about 5 feet behind the pilot, so those two units may give different values. Second, if he was rolling at high g, the roll rate and acceleration may affect either accelerometer and result in false readings. Pitch acceleration can also make false g reading.

So he may well have seen 11.2g but he likely did not really get there.



Even 9.8G seems a far better situation for that turn - and that was assuming the F-15 was under design weight.

It has been said a few times on here by John that the F-16 had a margin of about 150% so sustained 9G and structural limit ~13.5g for a few seconds etc - I am really not sure if that is a standard measure for all fighter aircraft.


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by KamenRiderBlade » 02 Jul 2016, 00:20

It seems like some pilots don't understand the pain that support staff & mechanics go through when they have to work extra hard to make sure the plane is safe after a Over G event.


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by spazsinbad » 02 Jul 2016, 01:18

8) In ye olden RAN FAA jet world of Vampires, Sea Venoms, Macchi MB326Hs & A4G Skyhawks it was a real bum clencher aftermath to explain to the Senior Pilot/CO why one may have overstressed an airframe - even by a small amount. The AEO Air Engineering Officer could take one on part of the inspection, if problems were found, with maintainers looking on (if looks could kill). :roll: :oops:


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by 35_aoa » 02 Jul 2016, 02:55

I honestly don't know what the threshold is…..I just know it is nice to hear the desk chief tell you it was only a level I. I know folks who have done 8.4ish (limit being 7.5) and still were only level I. You're buying a case of beer or a bottle of something either way for the guys/gals busting their butt to fix the jet you broke though :)

In the aerospace engineering world, 150% is a pretty common standard for absolute structural limit vs design limit. I know they deviated a bit from that to save weight in the space shuttle orbiter, and probably some other more exotic birds throughout history, but that seems to be the percentage go to number in terms of trade off between weight and performance.

basher54321 wrote:Thanks 35 - What G is a level II overstress at?

I was going from this because I was fairly certain you wont be getting anywhere near 12G in symmetric pitch -

viewtopic.php?f=22&t=24886&p=266875#p266875
The F-16 g limiter is not perfect and it can be defeated by a small amount, maybe .6 to .8 g. There is no way it would let you go to 11.2g in a turn. However there are two factors which may have led him to believe he did. First, his g meter is in the HUD and is driven by an accelerometer in the HUD electronics. The flight control accelerometer is about 5 feet behind the pilot, so those two units may give different values. Second, if he was rolling at high g, the roll rate and acceleration may affect either accelerometer and result in false readings. Pitch acceleration can also make false g reading.

So he may well have seen 11.2g but he likely did not really get there.



Even 9.8G seems a far better situation for that turn - and that was assuming the F-15 was under design weight.

It has been said a few times on here by John that the F-16 had a margin of about 150% so sustained 9G and structural limit ~13.5g for a few seconds etc - I am really not sure if that is a standard measure for all fighter aircraft.


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by 35_aoa » 02 Jul 2016, 03:10

KamenRiderBlade wrote:It seems like some pilots don't understand the pain that support staff & mechanics go through when they have to work extra hard to make sure the plane is safe after a Over G event.


Nobody goes out and intentionally overstresses an aircraft. But you end up out there, fighting hard, spending a lot of your time looking outside the aircraft by necessity, and you fly to a large extent, by feel of the aircraft. Unfortunately, the same displacement and/or force on the stick can yield very different things depending on your configuration and gross weight. That is the area where most folks are caught off guard, and to be honest, a quick trip to 9G doesn't feel much different than 6-7 if it is really momentary and the onset is rapid. Long way of saying that guys go out there and fly the jet the way it was intended to be flown, and sometimes mistakes are made. I think the tradition I mentioned above, of buying some cool beverages out of pocket for the troops is a way of reminding a guy about just what you mention. If you take it lightly and don't feel like a jerk who just needlessly downed an aircraft for everyone afterwards, you probably have other problems in life and leadership. I've got all the respect in the world for the guys out there sweating off their body weight in places like Dhafra/Bagram/Persian Gulf flight deck, trying to get jets back up for the flight schedule. No argument from me, they make this all happen, and an "I'm sorry I broke your jet, what can I get you from the NEX/PX/etc" is a good way to try and give a little back……same goes for other boneheaded mistakes that cause extra mx man hours. I remember over stressing a jet on det at Miramar once, on a late afternoon BFM hop. As quick as I could, I ran to the MCX, bought about 3 dozen beers of various types, and then tried to sneak past the maintenance control desk and the master chief with them……..in this day and age, booze in workspaces is somewhat frowned upon. He caught me red handed, and after giving me a good 15 second stink eye, said "you were the guy in 315 weren't you?"……I nod, and he just waves me past and says "I didn't see sh*t sir, go ahead" :)


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by bayernfan » 06 Jul 2016, 18:16

I'm sorry to share this link, but certainly fun to read the article from the famous ....... David Axe from WIB :D
(Hopefully I'm not breaking any rules for sharing this)

America's new super jet crushes all foes in war game

http://theweek.com/articles/633404/amer ... s-war-game

During mock combat, the F-35s reportedly shot down eight twin-engine F-15Es, for no losses of their own  —  this despite the 2015 revelation that the F-35 is inferior to a single-engine F-16 in a simulated dogfight. It's possible that the Lightning pilots have devised special air-combat tactics that take advantage of the F-35's stealth and cutting-edge sensors.

......
But with the F-35 eating more and more of a flattening budget, the flying branch shuttered one of its then-three adversary units, reducing the number of planes available to play the bad guys during war games.


You have to be amazed by how creative he is to criticize F-35. This time: F-35 beat mock enemy is because F-35 eats so much budget that USAF doesn't have the money to develop better mock enemy. :doh:


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