• Hi Guest! Forum rules have been updated. All users please read here.

The F-35 Discussion Topic (No Holds Barred II)

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
sferrin said:
HAH! Fat chance (either way ;D ). I'm wondering, where so much of the F-35 is controlled by software, if it's more a matter of refining the flight control laws, and what they will allow the pilot to do. The article in AvWeek seemed to suggest than they're fairly conservative at the moment. I find it extremely difficult to believe given all the flight testing they've done, the number of planes flying, and number of pilots trained, that they would discover only now that they had a dog.
There was the report of the F-35C having it's transonic acceleration increased by 45 seconds, that was several years ago. So I think that there is definitely room to discover that the F-35's performance is not identical to simulations.

As for improving flight control laws, recall that the F-35 had buffeting / transonic roll-off issues in the past. There may not be the total freedom to improve flight performance vs. what was demonstrated then.

Finally, I wonder what the impact of the engine issues (namely the rumored heating problems at lower altitude) have on the F-35 performance envelope. Is it possible that they cannot get enough cooling into the engine to run it at the desired speed? Perhaps engine restrictions lowered the energy of the F-35 below expectation. This can be fixed with the upcoming advanced engine program.
 

Dragon029

CLEARANCE: Top Secret
Joined
Mar 17, 2009
Messages
748
Reaction score
88
DrRansom said:
As for improving flight control laws, recall that the F-35 had buffeting / transonic roll-off issues in the past. There may not be the total freedom to improve flight performance vs. what was demonstrated then.
You might have just worded this oddly, but in the AvWeek article about this BFM, they specifically mentioned that they were able to practically eliminate the transonic roll-off through modifications to the flight control software (to where it's now a high-G-only event that creates <10 deg/s of roll for a fraction of a second; similar to flying through a tiny bit of turbulence).
 

marauder2048

"I should really just relax"
Joined
Nov 19, 2013
Messages
2,821
Reaction score
287
This article was published at the start of a Congressional Recess which will be followed very shortly by intensive
negotiations (under a veto threat) on the Defense Appropriations Bill. Brace yourself for more articles of this type.
 

bobbymike

CLEARANCE: Above Top Secret
Joined
Apr 21, 2009
Messages
10,082
Reaction score
1,138
sferrin said:
LowObservable said:
I would advise waiting until the facts are in before leaping to conclusions one way or another.


Not that I expect anyone to do so.
HAH! Fat chance (either way ;D ). I'm wondering, where so much of the F-35 is controlled by software, if it's more a matter of refining the flight control laws, and what they will allow the pilot to do. The article in AvWeek seemed to suggest than they're fairly conservative at the moment. I find it extremely difficult to believe given all the flight testing they've done, the number of planes flying, and number of pilots trained, that they would discover only now that they had a dog.
I recall reading an article very similar to this so-called 'report' but it was F-16s beating F-15s in close in dog fighting. I also recall a Youtube video, I believe, where F-15 pilots were training with Indian pilots and the pilot said the Indian modernized MIG-21s could be dangerous in a one on one dog fight.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
bobbymike said:
sferrin said:
LowObservable said:
I would advise waiting until the facts are in before leaping to conclusions one way or another.


Not that I expect anyone to do so.
HAH! Fat chance (either way ;D ). I'm wondering, where so much of the F-35 is controlled by software, if it's more a matter of refining the flight control laws, and what they will allow the pilot to do. The article in AvWeek seemed to suggest than they're fairly conservative at the moment. I find it extremely difficult to believe given all the flight testing they've done, the number of planes flying, and number of pilots trained, that they would discover only now that they had a dog.
I recall reading an article very similar to this so-called 'report' but it was F-16s beating F-15s in close in dog fighting. I also recall a Youtube video, I believe, where F-15 pilots were training with Indian pilots and the pilot said the Indian modernized MIG-21s could be dangerous in a one on one dog fight.
Yep. Mysteriously though, we're still flying those subpar aircraft that are dogmeat when faced with a Vietnam war era Mig-21. ;)
 

archipeppe

CLEARANCE: Top Secret
Joined
Oct 18, 2007
Messages
1,651
Reaction score
267
I give you my 2 cents: in Italy the F-35A was choose to replace the old (but still valuable) MRCA Tornado IDS, indeed Tornados are not known for their agility nor for their maneuvrability.
Any Tornado's crew could never think to survive in a dogfight with an F-16 for instance, indeed they served serveral European Air Forces (and not only) in the last 30 years or so on.


I don't see any problem if F-35 couldn't compete (if such news is true, obviously) with F-16, the point is that if the F-35 is better (and it should be far better, despite the teething problems) of all aircrafts it should replace.


That's it.


Ciao
Giuseppe
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
I was told yesterday by a couple of folks that the 5-page War is Boring document has been independently confirmed by major news outlets as being AUTHENTIC, and there is more to come--much more. And not to put to fine a point on it: the news is not good.

I'm thinking the US Navy (who has always been less than enthusiastic) ain't gunna buy no dog. The Navy don't own any F-22s, and therefore they would be counting on the F-35C to be a competent (their primary) ACM player. One thing about the Navy, after the Cutlass (Gutlass) they don't go for dogs. If the Navy won't buy their C dog then the Air Force, Marines, and international buys can't afford to buy their A and B dogs--even if they want to own a dog. Which they don't. The entire F-35 program is in big, big trouble. As a matter of pride and principle, nobody wants to buy and fly a dog, I don't care how invisible it is.
 

TomS

CLEARANCE: Top Secret
Senior Member
Joined
Apr 16, 2008
Messages
4,045
Reaction score
1,020
CxxTxx said:
I'm thinking the US Navy (who has always been less than enthusiastic) ain't gunna buy no dog. The Navy don't own any F-22s, and therefore they would be counting on the F-35C to be a competent (their primary) ACM player.
Naval Aviation has been looking for a manned stealth strike aircraft for decades, and the F-35C is going to be it. They won't care if it dogfights like an A-6 as long as it can go downtown in denied airspace.

Seriously, if they thought the F-35 was going to be their main ACM aircraft, they wouldn't have been content with the limited internal AAM stowage or the lack of an internal gun.
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
TomS said:
Naval Aviation has been looking for a manned stealth strike aircraft for decades, and the F-35C is going to be it. They won't care if it dogfights like an A-6 as long as it can go downtown in denied airspace.

Seriously, if they thought the F-35 was going to be their main ACM aircraft, they wouldn't have been content with the limited internal AAM stowage or the lack of an internal gun.
Well then, using that logic, what will the Navy be relying on as their main ACM aircraft for decades to come???
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
Official response from the JPO


https://www.f35.com/news/detail/joint-program-office-response-to-war-is-boring-blog
The media report on the F-35 and F-16 flight does not tell the entire story. The F-35 involved was AF-2, which is an F-35 designed for flight sciences testing, or flying qualities, of the aircraft. It is not equipped with a number of items that make today's production F-35s 5th Generation fighters.


Aircraft AF-2 did not have the mission systems software to use the sensors that allow the F-35 to see its enemy long before it knows the F-35 is in the area. Second, AF-2 does not have the special stealth coating that operational F-35s have that make them virtually invisible to radar. And third, it is not equipped with the weapons or software that allow the F-35 pilot to turn, aim a weapon with the helmet, and fire at an enemy without having to point the airplane at its target.


The tests cited in the article were done earlier this year to test the flying qualities of the F-35 using visual combat maneuvers to stress the system, and the F-16 involved was used as a visual reference to maneuver against. While the dogfighting scenario was successful in showing the ability of the F-35 to maneuver to the edge of its limits without exceeding them, and handle in a positive and predictable manner, the interpretation of the scenario results could be misleading. The F-35's technology is designed to engage, shoot, and kill its enemy from long distances, not necessarily in visual "dogfighting" situations. There have been numerous occasions where a four-ship of F-35s has engaged a four-ship of F-16s in simulated combat scenarios and the F-35s won each of those encounters because of its sensors, weapons, and stealth technology.


The release of this FOUO report is being investigated. The candid feedback provided by our test community is welcomed because it makes what we do better.


The disclosure of this report should not discourage our warfighters and test community from providing the Program Office and Lockheed Martin with honest assessments of the F-35's capabilities.



So to summarize, it is not a combat representative F-35 (missing software & hardware) and was limited to 7g vs the F-16 that could do 9g (yes, even with empty wing tanks) none of which was in DAxes article.. surprise surprise.
 

TomS

CLEARANCE: Top Secret
Senior Member
Joined
Apr 16, 2008
Messages
4,045
Reaction score
1,020
CxxTxx said:
Well then, using that logic, what will the Navy be relying on as their main ACM aircraft for decades to come???
Super Hornet. Really. Not ideal, but until (if) FA-XX happens, the Super Bug will be the Navy's main air defense fighter. Of course, they will also have AEGIS/Standard Missile for fleet air defense -- unlike the Air force, the Navy doesn't rely solely on aircraft for air combat.
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
I am willing to bet that once the USN gets the F-35 and starts training with it, they "will see the light" on Stealth & SA and the F-35 will soon take over in the fleet defense roll.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
SpudmanWP said:
Official response from the JPO


https://www.f35.com/news/detail/joint-program-office-response-to-war-is-boring-blog
The media report on the F-35 and F-16 flight does not tell the entire story. The F-35 involved was AF-2, which is an F-35 designed for flight sciences testing, or flying qualities, of the aircraft. It is not equipped with a number of items that make today's production F-35s 5th Generation fighters.


Aircraft AF-2 did not have the mission systems software to use the sensors that allow the F-35 to see its enemy long before it knows the F-35 is in the area. Second, AF-2 does not have the special stealth coating that operational F-35s have that make them virtually invisible to radar. And third, it is not equipped with the weapons or software that allow the F-35 pilot to turn, aim a weapon with the helmet, and fire at an enemy without having to point the airplane at its target.


The tests cited in the article were done earlier this year to test the flying qualities of the F-35 using visual combat maneuvers to stress the system, and the F-16 involved was used as a visual reference to maneuver against. While the dogfighting scenario was successful in showing the ability of the F-35 to maneuver to the edge of its limits without exceeding them, and handle in a positive and predictable manner, the interpretation of the scenario results could be misleading. The F-35's technology is designed to engage, shoot, and kill its enemy from long distances, not necessarily in visual "dogfighting" situations. There have been numerous occasions where a four-ship of F-35s has engaged a four-ship of F-16s in simulated combat scenarios and the F-35s won each of those encounters because of its sensors, weapons, and stealth technology.


The release of this FOUO report is being investigated. The candid feedback provided by our test community is welcomed because it makes what we do better.


The disclosure of this report should not discourage our warfighters and test community from providing the Program Office and Lockheed Martin with honest assessments of the F-35's capabilities.



So to summarize, it is not a combat representative F-35 (missing software & hardware) and was limited to 7g vs the F-16 that could do 9g (yes, even with empty wing tanks) none of which was in DAxes article.. surprise surprise.
Do you think the usual suspects will even notice that, let alone acknowledge it? Hell no. Not even here. What will they say? "Washington Post confirms horror story is true."
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
Well, the War is Boring story is true, but it is incomplete. JPO denies nothing from that War is Boring Story, it merely says that other technology will compensate for poor maneuverability.

Where did you get the 7G vs. 9G from, that isn't in the JPO release.

Oh, and I wonder about that last sentence in the JPO report.
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
This quote from the JPO response is the telling one:


While the dogfighting scenario was successful in showing the ability of the to maneuver to the edge of its limits without exceeding them, and handle in a positive and predictable manner,

It acknowledges several things, that it was under "limits" and software was keeping it from exceeding them. Since AF-02 has either 2B or 3i, the limit in software is 7g and the flight control laws on how to behave from 7g to 9g have net been installed (part of 3F).


This line, "handle in a positive and predictable manner" also indicates that they were testing flight control laws and not just letting the pilot pull the F-35 any which way he chose.


What is clear is the DAxe pick a couple of sentences from a 5-page report and twisted them completely out of context to fit his anti-JSF bias.
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
How is that quote telling? The limits can either be:

A. Testing limits, e.g. 7g, reduced authority, etc.
B. Max performance limits

No indication of that in this quote, though the April 2 Aviation Week article says that the dogfight was conducted "With No Limits." From that April 2nd quote, I get the impression that the F-35 test was without substantial limits.

From that, I can say that this quote is actually very narrow. It only states that the F-35 has good flight control within its flight regime, a theme also present in the April 2nd report. There is NO comment about the F-35's maneuverability relative to any other fight. The balance of comments about sensors versus maneuverability indicates that the War is Boring article is substantially correct about what happened.

Saying that the plane acted in a predictable and positive manner is good, but that is the minimum for a modern fighter. They don't say that the plane's performance is good.
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
There is either a limit (controlled by software) or not. If there is a limit, then it's 7g dictated by the Block (2B /3i).


In either case, no control laws exist in 2B/3i for the regime from 7g to 9g so even if you could push it above 7g, the plane would not behave "predictably" or optimally (the point of having control laws).


Once again, by withholding the complete 5-page report DAxe is able to cherry-pick a sentence or two and frame his entire hit-piece around it knowing that the JPO will not release the full report.
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
Since it's already been up to 9.9gs, I wonder what could be slowing it down after 6.5??? ;)


Did you notice that all the suggestions in the conclusions section can be done in software?


It's almost like they were "testing" something with an eye to making "improvements" and that what they were "testing" is not combat representative. B)
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
DrRansom said:
CxxTxx - care to give further hints to that 'not good news'
With the following caveat: I'm just the messenger. Please don't shoot me. I'm merely relating what was said to me.

Apparently, the fly-off was designed to allow the F-35 program to shine. AF-02 was configured with empty bays, and no compensating ballast, without 25 mm ammunition, and no compensating ballast, and with just enough fuel to get up, do the deal, and get down. The aircraft was not flown with sensor or helmet software because, "that stuff ain't even close to being ready."

The following quote captures the essence of the results: "In the real world, carrying realistic fuel and ordnance, the F-35A is [redacted] hopeless."

Okay, as related to me, the thinking by a lot of people is this:

1) Better change the "F" and "Fighter" part of the F-35 name, because, "it ain't ever gunna be that."

2) In time, the A-35 might make a fine short-range LO strike aircraft.

3) The Navy does not want, and can not use, a short-range strike aircraft. The C does not have the legs to go downtown. It can't even get to the suburbs. If the Navy does not buy, the cost for the other versions becomes deal-breaking excessive for everyone.

4) By the way, the NexGen bomber is pretty far along now, and fancy helmets and sensor fusion works just as good on a LO NexGen bomber as a short-range LO strike aircraft. The A will never be ACM dogfighter, it lacks the inherent ability. So, what can the A do on its short little, light ordnance carrying legs that a NexGen bomber can do even better?

5) Strip out whatever is good in the F-35 program and give it to a long-legged NexGen bomber, and then the Air Force begins work on the F-22 replacement. The Navy will be happy, happy as all hell, to get new Bugs while they work on a FA-XX that they actually like and want. And screw the Marines, they never needed $120 LO strike fighters to begin with.
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
Spudman - It sounds like there are two issues in that report:

A. Energy Maneuverability is awful and, if CxxTxx is correct, this is as good as EM is going to get this side of AETD. The high G states cannot be reached because of the high energy penalty. Again, if 7G limitation was an issue, that would be mentioned by now(!)

B. Control authority at high AoA can be relaxed to improve aircraft performance.

CxxTxx - if true, that sounds even more damning... Are your sources saying that the F-35's range is not as great as originally promised?
 

SpudmanWP

CLEARANCE: Top Secret
Senior Member
Joined
Nov 10, 2008
Messages
1,079
Reaction score
42
The telling part of the report is that the fixes proposed are all in software.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
CxxTxx said:
DrRansom said:
CxxTxx - care to give further hints to that 'not good news'
With the following caveat: I'm just the messenger. Please don't shoot me. I'm merely relating what was said to me.
By who? Sounds like BS to me. How would it be able to "shine" when software limited to 6.5 Gs against a 9G jet? Sounds more like what it was - a test flight. *yawn*
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
sferrin said:
How would it be able to "shine" when software limited to 6.5 Gs against a 9G jet? Sounds more like what it was - a test flight.
As is readily apparent from the report, an F-35A configured with empty bays, and no compensating ballast, without 25 mm ammunition, and no compensating ballast, and with just enough fuel to get up, do the deal, and get down is way too fat to get to 6.6 Gs, much less 9.

And with all due respect, no amount of software refinement is going to fix what could be the most disappointing, disgusting, and embarrassing paragraph that has ever been written about an American aircraft in the history of aviation:

Gun Defenses

No effective guns defense was found during this test. Various techniques were tried depending on aspect, energy, and closure. Attempts were made to maintain closure by staying in the 20-ish alpha region with lift vector on, while use rudder to get out of plane. Results were unpredictable as discussed above. For unloaded-roll-pull jinks, the slow pitch rate was evident in both the unload and pull. The result was a gradual out of plane maneuver which was easy to track. For floor and slow speed jinks, the high AOA control was adequate but there was no effective motion from the aircraft. The result was a target that was changing shape/attitude but not actually moving out of the pipper. Higher alpha usually just resulted in a larger planform target.

And once again folks, that's with a clean, empty aircraft. The good news is they can now strip the weight of the 25 mm cannon out of the F-35A. There will never be a time, reason or ability to use it.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
CxxTxx said:
sferrin said:
How would it be able to "shine" when software limited to 6.5 Gs against a 9G jet? Sounds more like what it was - a test flight.
As is readily apparent from the report, an F-35A configured with empty bays, and no compensating ballast, without 25 mm ammunition, and no compensating ballast, and with just enough fuel to get up, do the deal, and get down is way too fat to get to 6.6 Gs, much less 9.

And with all due respect, no amount of software refinement is going to fix what could be the most disappointing, disgusting, and embarrassing paragraph ever written in the history American aviation:

Gun Defenses

No effective guns defense was found during this test. Various techniques were tried depending on aspect, energy, and closure. Attempts were made to maintain closure by staying in the 20-ish alpha region with lift vector on, while use rudder to get out of plane. Results were unpredictable as discussed above. For unloaded-roll-pull jinks, the slow pitch rate was evident in both the unload and pull. The result was a gradual out of plane maneuver which was easy to track. For floor and slow speed jinks, the high AOA control was adequate but there was no effective motion from the aircraft. The result was a target that was changing shape/attitude but not actually moving out of the pipper. Higher alpha usually just resulted in a larger planform target.

And once again folks, that's with a clean, empty aircraft. The good news is they can now strip the weight of the 25 mm cannon out of the F-35A. There will never be a time, reason or ability to use it.
Still trying to figure out if you're just a troll or actually believe the crap you write. If you limited aircraft X to 6.5 Gs and allowed the F-35 it use it's full potential (9gs) you'd get exactly the same result, with aircraft X on the short end. Is this too difficult for you to understand or do you just not wish to acknowledge the fact?

From F-16.net:

"More to the point, the testing was towards for example, resulting recommendations. Tweaking the onset rate of high AoA, addressing 20-30 deg AoA transistion behavior. These are tests, intended to provide real data, with results/recommendations for such things as software changes. The tests were framed/set up to those purposes. I am guessing such things as maintaining energy using a Hi Yo Yo was out of scope, for example? The instructions were to pull high AoA. In fact finding those EM boundary conditions was likely an objective that was specifically aimed at exceeding otherwise prudent manuever options, to get that data.

I can imagine it would be a bit tough as a test pilot to keep driving into "mushy," when the setting was "dogfight." But someone needs to find (and tweak) "mushy" before operational pilots go there. See the evolution of the F-22 tactics and pilots backing off using as much as Thrust Vectoring heavy manuevering as the new toy shine had earlier encouraged.

I could be wrong but I suspect the test pilot if he came forward would refocus his critical comment towards the purposes he meant them.

All that said, yes "high SA" multi-ship environment engagements, is the target goal over a rare if ever, "high AoA" 1 v 1 yank and bank. That doesn't mean they aren't going to tweak and maximize high AoA yank and bank. They will. That means there should be more tests intentionally driving the aircraft into "mushy." The insight I got from the report was for example, that they need to, and no doubt will, crank the onset rate up some, since airframe limits were not stressed, and adjust transition behavior some. That's the meaningful type info here."
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
sferrin said:
What are you smoking? As another poster pointed out they've already tested it to 9.9 Gs.
As long ago discussed: That was a single maneuver designed by the LockMart Propaganda Office (TM) to record an instantaneous 9.9 G on an accelerometer so they (and the F-16.net F-35 Fanboys) could promulgate, "The F-35 is a 9.9 G aircraft!!"

NOW PROVE ME WRONG.

Emotionally, I know its going to be tough, but it's time to give it up. The national security of our country (and the world) is at stake. And LockMart is selling us a trillion dollar dog.

(I'm out. This is F-16.net F-35 Fanboy stuff is way too crazy. You can actually see them working in real time over there to develop a written rebuttal to this report that they can, "spew it out all over the web.")
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
sferrin - where does it state that the F-35 was limited to 6.5 G's? You keep saying that, but you do not provide any evidence.

If you read the report, you see that the pilot cannot go above ~6.5 G's, but for energy management reasons. There is NO statement about 6.5G limitations. Mind you, the F-16 is likely limited to 7G's due to the drop tanks. Even if a 6.5G limitation existed (we have no evidence), then the advantage of the F-16 still isn't great.

What about the statement that the F-35's energy management is worse than a F-15E? Anything for that?

CxxTxx - where do you get that the F-35 will be short ranged? Has the range come down due to weight issues?
 

LowObservable

CLEARANCE: Top Secret
Senior Member
Joined
Oct 18, 2006
Messages
2,191
Reaction score
100
The telling part of the report is that the fixes proposed are all in software.

Too right, because nobody's going to look at hardware changes at this point.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
DrRansom said:
sferrin - where does it state that the F-35 was limited to 6.5 G's? You keep saying that, but you do not provide any evidence.

If you read the report, you see that the pilot cannot go above ~6.5 G's, but for energy management reasons. There is NO statement about 6.5G limitations. Mind you, the F-16 is likely limited to 7G's due to the drop tanks.
Software build is what limits it to 6.5. Go follow the discussion on F-16.net. As for the tanks, they're rated for 9 empty. There are both F-16 pilots and at least one of the designers in those threads.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
CxxTxx said:
As long ago discussed: That was a single maneuver designed by the LockMart Propaganda Office (TM) to record an instantaneous 9.9 G on an accelerometer so they (and the F-16.net F-35 Fanboys) could promulgate, "The F-35 is a 9.9 G aircraft!!"

NOW PROVE ME WRONG.
'scuse me, you're the one making the claim that it was a propaganda piece. Support your assertion. Oh right, you can't. Shocker.

CxxTxx said:
and the F-16.net F-35 Fanboys
So actual, real live F-16 pilots, and a guy who helped design the F-16, are "fanboys"? And just exactly who are you and what are your credentials sweetie?
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
LowObservable said:
The telling part of the report is that the fixes proposed are all in software.

Too right, because nobody's going to look at hardware changes at this point.
Why would you even consider a hardware change if it can be done in software?
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
sferrin said:
DrRansom said:
sferrin - where does it state that the F-35 was limited to 6.5 G's? You keep saying that, but you do not provide any evidence.

If you read the report, you see that the pilot cannot go above ~6.5 G's, but for energy management reasons. There is NO statement about 6.5G limitations. Mind you, the F-16 is likely limited to 7G's due to the drop tanks.
Software build is what limits it to 6.5. Go follow the discussion on F-16.net. As for the tanks, they're rated for 9 empty. There are both F-16 pilots and at least one of the designers in those threads.
If the aircraft is software limited too 6.5G's, then why is that not reported in any of the JPO statements? Also, how would increase the G limit improve energy management? There is no requirement in this dogfight to go up to 9 G's, because the pilot cannot even operate at 6.5. Increasing the G limit would have changed nothing.

As for hardware changes, what can be done to fix poor Energy Management? Remember, that is the heart of the test pilots complaint. He could not access the high AoA without losing unacceptable amounts of energy.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
DrRansom said:
If the aircraft is software limited too 6.5G's, then why is that not reported in any of the JPO statements?
Ask them. The document was for internal consumption and those who need to know would know.


DrRansom said:
He could not access the high AoA without losing unacceptable amounts of energy.
What do you think happens to pretty much any aircraft when it goes high AOA?
 

overscan (PaulMM)

Administrator
Staff member
Joined
Dec 27, 2005
Messages
12,267
Reaction score
2,961
The PDF is interesting. The War Is Boring article isn't.


The F-15 has the best EM of the teen series. The F-35 was never going to match it in a clean configuration. The F-16 was the next best, with F-18 trailing behind. F-18 fought best in the low speed, high AOA arena. F-35 may recover some ground when fuelled up and armed, as its external drag won't alter whereas a teen fighter is now hauling missiles and fuel tanks.

The test PDF results show clearly:

1) F-35 is more like F-18 in general energy manouvre characteristics than the F-15 or F-16.
2) Current control laws prevent useful exploitation of the high AOA capabilities of the F-35.

Every aircraft design is a set of compromises. In some areas, I am certain the F-16 may beat the F-35 in a gun fight even with the control tweaks applied. Hell, MiG-21s can beat F-15s in the right circumstances, but the USAF didn't sell all their F-15s and buy MiG-21s.

The goal of the F-35 is rough parity with the teen series in general in this area, NOT superiority. With the control software updated, it seems likely that a well-flown F-35 would be able to fight on roughly equal terms. Like F-16 vs F-18, F-15 vs Su-27, each design has areas of superiority and weakness, the successful pilot will steer the fight towards the region in which his plane has superiority. If the F-35 gets into a WVR fight, the pilot has already lost the first part of this battle by not winning the BVR fight.


All this "this fighter is rubbish it can't even outmanouvre an F-16" rubbish is just total BS.



1) We don't know its true.
2) If it is true, we don't know if it matters to the people buying it.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
PaulMM (Overscan) said:
1) We don't know its true.
2) If it is true, we don't know if it matters to the people buying it.
The thing is customers aren't rushing to cancel the program. The USAF, USN, and others aren't going to accept a dog. And it's not like there wouldn't be alternatives if they were desired. The F-16, F-15, and Super Hornet lines are still running. The F-22 line could be reconstituted (wouldn't be cheap but it could be done) and the three Eurocanard lines are running. Yet nobody is scrambling to cancel their orders, or cancel the program. Could be they know things we wish we did but don't have access to.
 

DrRansom

I really should change my personal text
Joined
Dec 15, 2012
Messages
534
Reaction score
9
sferrin said:
Ask them. The document was for internal consumption and those who need to know would know.
This has to set the record for one of the most dishonest statements made. The JPO released a Press Release, to the Washington Post, about the document leak. That statement was for Maximum Public Consumption. To state otherwise is ...



What do you think happens to pretty much any aircraft when it goes high AOA?
Well, there is a difference between losing energy (which everybody does) and losing too much energy to make that flight regime nearly useless. That seems to be the distinction the test pilot made.

Which gets to PaulMM's point, the pilot makes two comments about the high AoA regime:
A. Poor control software (this can be fixed)
B. Unacceptable energy loss (this can't be easily fixed)

If A is fixed, the 20 degree AoA regime may be the F-35's best. However, that doesn't make it good, because of the energy management issues.
 

CxxTxx

You ate my glittery ponies?
Joined
May 9, 2013
Messages
54
Reaction score
0
We knew for a fact in January, 2013 that the F-35 was struggling with its ACM kinematics:

"The program announced an intention to change performance specifications for the F-35C, reducing turn performance from 5.1 to 5.0 sustained g's and increasing the time for acceleration from 0.8 Mach to 1.2 Mach by at least 43 seconds," reads the report prepared by J Michael Gilmore, the Pentagon's DOT&E. "These changes were due to the results of air vehicle performance and flying qualities evaluations."

The US Air Force F-35A's time has slipped by eight seconds while the US Marine Corps short take-off vertical landing (STOVL) F-35B's time has slipped by 16 seconds. However, turn rates for both the A and B models have been impacted more severely than the USN variant. Sustained turning performance for the F-35B is being reduced from 5G to 4.5G while the F-35A sinks from 5.3G to 4.6G according to the report.

http://www.flightglobal.com/news/articles/pentagon-lowers-f-35-performance-bar-381031/

And that the reduced the F-35 performance specifications would have significant operational impacts:

http://www.flightglobal.com/news/articles/reduced-f-35-performance-specifications-may-have-significant-operational-381683/

David Axe's "scoop" shouldn't come as a surprise to anyone... In a turning fight, the F-35A is a 4.6 G aircraft, which is a bit less than a fully loaded F-105 carrying external bombs and drop tanks.
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
DrRansom said:
sferrin said:
Ask them. The document was for internal consumption and those who need to know would know.
This has to set the record for one of the most dishonest statements made. The JPO released a Press Release, to the Washington Post, about the document leak. That statement was for Maximum Public Consumption. To state otherwise is ...
Whoops. Thought you were talking about the original document. Do you honestly believe Joe Blow is going to know how different software versions affect the aircraft?
 

sferrin

CLEARANCE: Above Top Secret
Senior Member
Joined
Jun 3, 2011
Messages
13,265
Reaction score
1,290
CxxTxx said:
David Axe's "scoop" shouldn't come as a surprise to anyone... In a turning fight, the F-35A is a 4.6 G aircraft, which is a bit less than a fully loaded F-105 carrying external bombs and drop tanks.
Wow. You actually believe that. Uhm, okay. . .
 
Top