The F-35 Thread

[garrya]

Well you certainly know how to ask mr. Johnwill misleading questions Garrya :doh:

 

1. His first answer neither confirms nor denies anything I've said, he simply states what we already know = the F-35 has a higher AoA limit than the F-16 and thus can generate a higher initial turn rate at low speeds, that's no secret.

We started this whole discussion about body lift and what not because on page 339 , i questioned your assessment regarding F-35 CL and ITR. Then now when we got reply from John , you changed your mind and said that is what we know at the start ????? His first answer also made very important point regarding lift and AoA " relationship between lift and AoA is non linear, and it is also nonlinear vs Mach number, so there is no way to extrapolate AoA at low speed to IRT at combat speed"

 

 

Then again , why would it be limited to slow speed only ? what if F-35 AoA at high speed ( mach 0.7-0. 8) is higher than F-16 also. Ultimately , like i stated at start we dont know its max CL so you cant conclude that its ITR is bad

 

2. I never compared tubular vs boxy in terms of lift, that's once again entirely you're own creation. What I said was "airfoil shape vs boxy". Why? Because I was talking about the F-16's lifting body:

Firstly , the whole body , not just that specific part will generate lift at positive AoA (AFAIK , aircraft made high G turn at positive AoA )

Secondly , if that was what you mean then why didnt you said it the first time i brought up tube body ? why mention it just now when we got reply from John ?

 

 

 

And now you have to prove that small area next to F-16 wing and its body will generate more lift than the whole underside of F-35 it may be more efficient per square inchs (by how much we dont know). But large part of F-35 is its fuselage

 

 

You're not helping yourself garrya....

And how am i wrong exactly ?, as shown negative stable aircraft dont all have same amount of "negative" ( their relative location between CoL and CG isn't all the same )

 

 

LEADING EDGE garrya, i.e. it's the area infront of the wing. I am talking about the entire blending of wing and fuselage. LERX only makes up the front part.

Back to basic aerodynamics, an assymetric airfoil generates lift at 0 AoAwhich is the shape of the F-16's body (aside from the engine ofcource, the part you somehow like to focus on, also in your questions for mr Johnwill).

 

Would you forget about the tube already! The F-16 is not a bloody tube!! :wallbash:

Why do i focused on the whole body and LERX ? because the whole flat underside of F35 will also generate lift. And not long ago , we had a similar discussion in this thread , you also said F-18 has better body lift because its underside is less boxy than F-35.So obviously i would assume you talked about the entired fusalage

 

 

 

 

Airfoil shape vs box shape garrya, that's the discussion, please write it down for yourself to remember this time.

You just keep shifting goal post

 

 

Why are we talking about LERX vortices now??

Because it contribute significantly to body lift at AoA

 

 

 

 

 

Mein gott in himmel, lord our saviour..... No'one "drew" a new ITR line, the line continues on its curve up to the ultimate load factor, it doesn't just suddenly go *boob* and takes a bend. I've already showed you the lift curve up to 7.5 G's earlier, extrapolating that line to 9.5's isn't a problem and it's not drawing something that isn't there - infact it's exactly what the person who made the strike fighters comparison paper did, hence his mention of the 9.5 G recommended load limit. I hope you eventually will understand this.

Does that ITR line appear in the EM graph or not ? No. So basically you draw a curve outside it. You can argue that the curve is valid because that is ITR that pilots will achieve when he excess the recommended G limit. No problem, but if that what we do then we should do that to all aircraft in comparison , not just F-14. Why should we limited ITR of F-35A to 9 G and F-35C to 7.5G if it has been tested to 9.9G then ? , why should we limited F-15 ITR to 9 G if it has excess 12G before in combat ..etc so and so on. Either we use the recomemded limit or we dont , there no middle ground.

 

 

 

 

 

 

I didn't show a value for 10 kft garrya, I showed one for 25 kft at Mach 0.8.

 

That not what you posted the first time you said he is wrong .Here is what you posted in case you forgot :

 

 

 

 

 

Again the figures won't be off by such an amount even when this is considered, and I'm talking specifically about the G figures.

Unless you made some calculation to show ,Iam not so sure about that , F-16 late and early version are a few thoundsands pounds different and that translate to quite different performance. I dont believe that changing fuel load wont changing kinematic performance dramatically

 

Do you see now how a doghouse plot moves with altitude?

And? your point is ?

Edited November 15, 2016 by garrya

[Hummingbird]

In an effort to avoid this awful "quoting ballet" from continuing I'm going to try to keep my answers tightly packed together from this point on.

 

Garrya,

 

There are two basic ways in which you can improve the ITR of an aircraft, one arguably more useful & "actual" than the other.

 

1. Significantly increase nose authority:

This is the less natural and more forced approach in which a large portion of the aircraft's lifting surfaces will end up in a stalled state and thus generate massive amounts of drag and little lift in the process. In other words with this approach you end up with a very initial & short lived ITR, one where your aircrafts nose will quickly end up pointing in another direction than it's actually flying as it's not actually capable of generating the lift necessary to quickly haul the aircraft round the bend.

 

 

2. Maximize lift:

The most common and natural approach to achieve a high ITR is by generating a lot of lift in relation to weight, and preferably very efficiently to keep the L/D ratio as high as possible. Maximising lift means choosing the ideal AoA and keeping large portions of the aircraft's lifting surfaces from ending up stalling. By doing this you achieve a higher actual turn rate that is a lot longer lasting than the first approach as it doesn't generate nearly as much drag and thus keeps the rate from degrading as fast.

 

 

This is the difference I am seeing between the F-35 and F-16:

 

The F-16 is by virtue of its design, where no aerodynamic compromises needed to be made for stealth reasons, most likely capable of generating a noticably higher lift to weight ratio than the F-35, and thus it is capable of actually hauling itself round a full turn a lot quicker.

 

By comparison the more stubby F-35, whilst most likely not capable of generating as high a lift to weight ratio as the F-16, isn't held back by any AoA limiter and thus is initially capable of achieving a higher rate of change in attitude (nose authority) at speeds where the load limit won't be breached - however this comes with the penalty of quickly burning away energy, leaving the aircraft with little airspeed to maneuver effectively afterwards. In other words the F-35 can pull the brake real fast, but it won't actually be hauling itself around a full turn very fast by comparison.

 

 

This is about as simple as I can put it for you garrya without going real technical...

Edited November 15, 2016 by Hummingbird

[Boagrius]

T-50 is planned to have DIRCM, ie. a laser that blinds seeker heads of IR guided missiles so it would be essentially invulnerable against AIM-9X or similar missiles. It could also be invulnerable to radar missiles using combination of tactics, stealth and jammers. If you really need to kill it then how would you do it besides gunning it down? Adding all that gadgetry also into F-35 is possible and relatively easy but you can't improve it's performance in gunzo with similar ease.

 

Anyways it could be premature to declare dogfights to be history as new methods for disabling missiles are becoming reality. It could be possible to build missiles that are resistant to these methods but to me it seems uncertain at this moment if things will stay as is or not.

 

I don't think there's any doubt that F-35 is going to own any non stealthy plane but that's not the threat it needs to be able to deal with in the future. This is especially true for the nations that don't have F-22. F-35 needs to stay relevant weapons platform for some 30 years into the future.

 

I am aware of this, however you have to wonder how effectively the T50 will be able to cue its DIRCM system (101KS-O) based on the limitations of its MAWS (101KS-U). Last time I checked the T50 used a UV based MAWS which (again, to my knowledge) does well to detect the ignition of nearby rocket motors but poorly/not when it comes to physically tracking an incoming missile in flight. The fact that EODAS is an IR based system leaves it better placed as a means of giving future DIRCM systems (~Blk 5?) accurate data about where to direct their energy (from a violently maneuvering platform no less!) when needed.

 

It's likely to be decades before the two jets could plausibly meet each other in the sky in meaningful numbers. In that timeframe you could well be looking at F35D/E/F's running new ADVENT/AETD engines, DIRCM of their own/DEWs, SACM, MSDM, T3, GaN upgraded APG81, improved RAM coatings, networked UAV swarms... the list goes on.

 

I agree it's extremely difficult to predict what the operating environment will be like post ~2030, but the idea that all the "fancy gadgets" will somehow just perfectly cancel each other out and reduce everyone to Korean War style tail chase gunfights strikes me as a gross oversimplification of what is likely to be a very complex situation with a multitude of (more) plausible outcomes.

Edited November 16, 2016 by Boagrius

[GGTharos]

Who cares about DIRCM and missiles, F35 is getting AA lazorz.

[Rangi]

HOL - home on laser seems a good bet for a duel mode seeker...

Trump still talking down F-35, but I assume he will be talked around if anyone can get some facts into him.

 

https://www.bloomberg.com/news/articles/2016-11-15/trump-s-doubts-on-f-35-jet-cast-pall-on-pace-of-defense-buildup

[GGTharos]

Home on laser is useless when the laser destroys your seeker. It's a bit like saying 'home on CIWS'.

[pyromaniac4002]

where no aerodynamic compromises needed to be made for stealth reasons

 

Behold the inherent flaw in your thinking..

 

Stealth and aerodynamic considerations stopped being mutually exclusive design attributes in the mid-to-late 80s. For the Nighthawk, oh hell yes, stealth made that thing the ugliest object that air ever ran its fingers over. I'm pretty sure the F-117 is somewhere near the top of the list of the objects the atmosphere most begrudgingly lifted off of the ground. But if you can't take a look at an F-22 demo and implicitly understand that they didn't compromise on aerodynamics one bit to achieve stealth in that design, you'll never get it. The F-35's kinematic performance is not inherently compromised because it is a stealth aircraft.

[Rangi]

Home on laser is useless when the laser destroys your seeker. It's a bit like saying 'home on CIWS'.

 

I meant with the dazzle lasers, obviously the high power burn lasers would need a new strategy.

[Hummingbird]

Behold the inherent flaw in your thinking..

 

Stealth and aerodynamic considerations stopped being mutually exclusive design attributes in the mid-to-late 80s. For the Nighthawk, oh hell yes, stealth made that thing the ugliest object that air ever ran its fingers over. I'm pretty sure the F-117 is somewhere near the top of the list of the objects the atmosphere most begrudgingly lifted off of the ground. But if you can't take a look at an F-22 demo and implicitly understand that they didn't compromise on aerodynamics one bit to achieve stealth in that design, you'll never get it. The F-35's kinematic performance is not inherently compromised because it is a stealth aircraft.

 

The F-22's design is hampered by stealth, just not to anything near the degree of the F-117 which was a first attempt at the concept of stealth. The F-22 designers also made up for these sacrifices by adding A LOT of wing and A LOT of thrust with vectoring nozzles to boot.

 

By comparison the F-35 suffers more due to all the mission requirements it had to meet on top of stealth, which is what made it end up so stubby. Had they decided on a larger twin engined stealth aircraft it would've affected it less assuming the same mission requirements, due amongst other things to a larger possible internal volume. The T-50 is a good example of this.

[Ktulu2]

By comparison the F-35 suffers more due to all the mission requirements it had to meet on top of stealth, which is what made it end up so stubby. Had they decided on a larger twin engined stealth aircraft it would've affected it less assuming the same mission requirements, due amongst other things to a larger possible internal volume. The T-50 is a good example of this.

 

Well, the payload will indeed affect the performances of a lighter aircraft compared to a bigger one with the same T/W. This being said, the F-35 is heavier than the hornet, which I think has enough payload for pretty much anything when you have more than 1 plane doing a mission, so putting bigger wings on it wouldn't have helped it that much aside from raising the operational cost for loaded performances.

 

Now for increasing internal volume, well, that's what made the plane chubby in the first place, so you either scale it up and make it slicker, keeping around the same internal volume, or you don't solve the problem.

 

Finally, If you say bigger wings would have helped the lightning with low speed handling, It is true, but maybe not in a significant way. I you doubt this, compare the wing loading of an F-18 and F-15. The -18 has the bigger wing loading, but also has the better low speed handling so you can't be sure of that without deeper analysis.

[Hummingbird]

Well, the payload will indeed affect the performances of a lighter aircraft compared to a bigger one with the same T/W. This being said, the F-35 is heavier than the hornet, which I think has enough payload for pretty much anything when you have more than 1 plane doing a mission, so putting bigger wings on it wouldn't have helped it that much aside from raising the operational cost for loaded performances.

 

Now for increasing internal volume, well, that's what made the plane chubby in the first place, so you either scale it up and make it slicker, keeping around the same internal volume, or you don't solve the problem.

 

 

Seems like you're saying the same as me, but the basic point is that full stealth always hampers aerodynamics simply because optimum aerodynamics ≠ optimum stealth. Ofcourse the more and more advanced computational fluid dynamics & radar simulation programs of today help designers strike a much better balance between the two than was possible back when the F-117 was designed, but the basic problem will always be there for as long as shape dictates stealth capabilities.

 

The best way to mitigate this shape problem by conventional means is 1) to increase size so that your weapon bays don't take up as large a percentage wise space 2) tailor you craft to two specific roles and don't do a jack of all trades.

 

Finally, If you say bigger wings would have helped the lightning with low speed handling, It is true, but maybe not in a significant way. I you doubt this, compare the wing loading of an F-18 and F-15. The -18 has the bigger wing loading, but also has the better low speed handling so you can't be sure of that without deeper analysis.

 

Well that is actually a poor example since the F-18 features very large LE & TE high lift devices + large LERX, whilst the F-15 has neither. Hence the F-18's better low speed handling is a direct result of it generating significantly more lift pr. square wing area than the F-15.

 

The F-35 doesn't have this advantage compared to the F-16 or F-18, thus it's most likely going to end up less maneuverable.

Edited November 17, 2016 by Hummingbird

[garrya]

In an effort to avoid this awful "quoting ballet" from continuing I'm going to try to keep my answers tightly packed together from this point on.

 

Garrya,

 

There are two basic ways in which you can improve the ITR of an aircraft, one arguably more useful & "actual" than the other.

 

1. Significantly increase nose authority:

This is the less natural and more forced approach in which a large portion of the aircraft's lifting surfaces will end up in a stalled state and thus generate massive amounts of drag and little lift in the process. In other words with this approach you end up with a very initial & short lived ITR, one where your aircrafts nose will quickly end up pointing in another direction than it's actually flying as it's not actually capable of generating the lift necessary to quickly haul the aircraft round the bend.

 

 

2. Maximize lift:

The most common and natural approach to achieve a high ITR is by generating a lot of lift in relation to weight, and preferably very efficiently to keep the L/D ratio as high as possible. Maximising lift means choosing the ideal AoA and keeping large portions of the aircraft's lifting surfaces from ending up stalling. By doing this you achieve a higher actual turn rate that is a lot longer lasting than the first approach as it doesn't generate nearly as much drag and thus keeps the rate from degrading as fast.

 

 

This is the difference I am seeing between the F-35 and F-16:

 

The F-16 is by virtue of its design, where no aerodynamic compromises needed to be made for stealth reasons, most likely capable of generating a noticably higher lift to weight ratio than the F-35, and thus it is capable of actually hauling itself round a full turn a lot quicker.

 

By comparison the more stubby F-35, whilst most likely not capable of generating as high a lift to weight ratio as the F-16, isn't held back by any AoA limiter and thus is initially capable of achieving a higher rate of change in attitude (nose authority) at speeds where the load limit won't be breached - however this comes with the penalty of quickly burning away energy, leaving the aircraft with little airspeed to maneuver effectively afterwards. In other words the F-35 can pull the brake real fast, but it won't actually be hauling itself around a full turn very fast by comparison.

 

 

This is about as simple as I can put it for you garrya without going real technical...

 

Well , higher AoA turn will generate more drag , no doubt. But i disagree that it is just nose pointing ( as in post stall maneuver). F-35 has max CL at AoA higher than max allowable AoA of F-16 so while it generate more drag , it also generate more lift.As an anecdote, during the infamous "dogfight test" the pilot talked about flying in the "blended region" (for the FBW software to know where to go from traditional control to high AoA control schemes) at 20-26 degrees. He mentions that as 26 degrees the aircraft is actually still "shallow" and would be able to roll well (still a lift margin on the wing) and that the beginning of the "blended region" should be pushed up to 30 degrees or greater from 20. Of course as mentioned earlier , a high drag turn such as one performed by F-35 at high AoA will deplete aircraft of speed very quick, but it is also noted by the Norwegian pilots that f-35 recovered speed rapidly compare to F-16 (at dogfight speed , obviously).

"When we begin I'm “only” doing 400kts," says Hanche. "I purposely make a hard turn towards “Red Air” in full afterburner, so hard I loose speed. Such a hard turn can be felt physically, because the high AOA (angle of attack) makes the plane shake somewhat – a bit like driving fast on an old gravel road. It's still easy to control and it's no problem getting back up to speed. After just a short time the plane is supersonic so that I can fire the missile at about mach 1,2."

 

"The ability to point towards my opponent makes me able to deliver a weapon sooner than I'm used to. It forces my opponent to react more defensive and gives me the ability to slow down fast," Hanche says. "Since I can slow down fast I can point my plane at my enemy for longer before the roles are reversed. The backside is that you lose energy, but it's not really a problem. The plane has so much engine power and low drag that the acceleration is awesome. With an F-16 I would have had to dive to gain as much speed after a hard turn."

"I’m also impressed by how quickly the F-35 accelerates when I reduce the AOA. High AOA produces lots of lift, but also tremendous induced drag. When I «break» the AOA, it is evident that the F-35 has a powerful engine. "

"Another aspect is the kind of reaction I get when I push the stick forward; the F-35 reacts immediately, and not delayed like the F-16."

https://theaviationist.com/2016/03/01/heres-what-ive-learned-so-far-dogfighting-in-the-f-35-a-jsf-pilot-first-hand-account/

 

Now before you question the pilot opinion and said " how can F-35 has better acceleration than F-16 if it has lower T/W , and more draggy airframe " i already ask that question for you and here is the answer:

Edited November 17, 2016 by garrya

[Ktulu2]

The F-35 doesn't have this advantage compared to the F-16 or F-18, thus it's most likely going to end up less maneuverable.

 

Given the good high AoA characteristics of the F-35 from what I've heard, that could give it something the viper doesn't have. My point wasn't that WL is 200% meaningless, just that until you get your hand on a chart or some decent info, looking at the bird won't tell you about a good FCS or optimisation.

[Hummingbird]

garrya,

 

Can't you see that litterally none of what you just qouted contradicts any of what I've said? Infact the Norwegian pilot indirectly confirms all I've said - he just can't be direct about it however for rather obvious political reasons at this very moment, the project would be drowned in even more flak from the public than it's already recieving if he directly pointed out a weakness.

 

As mentioned the F-35 is capable of reaching a high alpha (~50 deg IIRC) really fast, which on the offense provides the pilot with the ability to lead his target for longer in certain situations than if he hadn't been able to go past say 26 deg AoA (like the F-16), but the fun stops really quick once the target crosses his pipper as, assuming it's an F-16, then the F-35 by comparison simply lacks the lift necessary to generate the rate needed to maintain lead, the F-16 holding the advantage in actual ITR and STR.

 

In defense the high alpha ability allows the F-35 pilot to "pull the brakes" so to speak, forcing a pursuing F-16 to overshoot, the F-16 simply can't dump speed that fast, but once again this will be of limited comfort if the F-16 pilot simply extends in the vertical - the same tactic Eurofighter pilots used to beat F-22 pilots who couldn't resist dumping all their energy in extreme AoA maneuvers. PS: This is not to compare the F-35 with the F-22, they are two completely different beasts in terms of kinematic performance (!), the F-22 actually possessing the lift necessary to quickly haul itself round a turn if the pilot chooses not to dump it all with high alpha showboating.

 

Finally regarding straight line acceleration, I have little doubt that the F-35 rockets off the line, the engine is incredibly powerful and straight on the drag of the F-35 probably is comparable to that of a combat loaded F-16. It's once the turning starts that a real difference in drag will be felt.

Edited November 17, 2016 by Hummingbird

[Darkbrotherhood7]

This is what pilots said when comparing the F-35 against 4th gen fighters:

 

 

 

The F-35A was not designed to be an air superiority fighter, but the pilots interviewed conveyed the picture of a jet that will more than hold its own in that environment—even with its current G and maneuver restrictions. In the words of an F-16C Weapons School Graduate and instructor pilot now flying the F-35A, “Even pre-IOC,[26] this jet has exceeded pilot expectations for dissimilar combat. (It is) G-limited now, but even with that, the pedal turns[27] are incredible and deliver a constant 28 degrees/second. When they open up the CLAW, and remove the (7) G-restrictions, this jet will be eye watering.”

 

http://www.heritage.org/research/reports/2016/08/operational-assessment-of-the-f-35a-argues-for-full-program-procurement-and-concurrent-development-process

Edited November 17, 2016 by Darkbrotherhood7

[garrya]

garrya,

 

Can't you see that litterally none of what you just qouted contradicts any of what I've said? Infact the Norwegian pilot indirectly confirms all I've said - he just can't be direct about it however for rather obvious political reasons at this very moment, the project would be drowned in even more flak from the public than it's already recieving if he directly pointed out a weakness.

 

As mentioned the F-35 is capable of reaching a high alpha (~50 deg IIRC) really fast, which on the offense provides the pilot with the ability to lead his target for longer in certain situations than if he hadn't been able to go past say 26 deg AoA (like the F-16), but the fun stops really quick once the target crosses his pipper as, assuming it's an F-16, then the F-35 by comparison simply lacks the lift necessary to generate the rate needed to maintain lead, the F-16 holding the advantage in actual ITR and STR.

No , F-16 hold advantage in STR but not ITR

It not just nose pointing like in case of TVC (in case of F-35 the direction of travel also changed , not just the direction of the nose ), F-35 capable of generates higher CL because it is controllable at higher AoA than F-16 , F-16 max AoA , especially at high G is limited by the CAT limiter , this in turn reduce its CLmax

At 9G , even with CAT I limiter the maximum AoA is only 15 degrees

 

However, CL max of F-16 dont stop until AoA of about 35 degrees, even between 15 and 20 degree , the CL different is very significant. At high G turn , F-16 ITR is limited by its AoA rather CLmax of the airframe

For F-35 since its controlable AoA is higher , its CLmax at high G will also be higher , thus it will be able to generate higher lift and as a result higher ITR (there is nothing unconventional about this ITR , it the same case for all aircraft without an AoA limiter and controllable at high AoA). Disadvantage is obviously bigger drag , but as stated F-35 regain speed even better than F-16 due to its engine

 

 

 

In defense the high alpha ability allows the F-35 pilot to "pull the brakes" so to speak, forcing a pursuing F-16 to overshoot, the F-16 simply can't dump speed that fast, but once again this will be of limited comfort if the F-16 pilot simply extends in the vertical -.

in which case F-35 can break AoA or dive to regain speed, with its enormous thrust that would be quick , like the pilot said F-35 can regain speed as quick as F-16 in a dive

Edited November 17, 2016 by garrya

[garrya]

This is what pilots said when comparing the F-35 against 4th gen fighters:

 

Remember though , this is with 7G limit in place

[Hummingbird]

*sigh*

 

garrya,

 

The CAT system is there to make sure the aircraft doesn't "over G", it doesn't limit the F-16 at high speed at all, it safeguards it.

 

No aircraft, and that includes the F-35, will be pulling much over 15 deg AoA at high speed. Do that and the wings come off.

 

The F-35's high AoA capability is only useful at relatively low speeds, and here the F-16 isn't really limited being able to pull around 26-30 deg AoA, which is more than enough to ensure a high lift induced ITR. Go beyond that AoA and lift generating parts of the aircraft start stalling, lowering the overall lift generated, despite wether or not the wings gain a marginal increase in CL.

[Hummingbird]

This is what pilots said when comparing the F-35 against 4th gen fighters:

 

http://www.heritage.org/research/reports/2016/08/operational-assessment-of-the-f-35a-argues-for-full-program-procurement-and-concurrent-development-process

 

Interesting charts Darkbrother, thanks.

 

It's clear when looking at the F-15 for reference that they're using an F-16 with wing bags for the comparison though as the F-16's STR is higher than that of the F-15 under most conditions. Albeit again pilot opinions as always differ wildly.

 

In the end the specifics won't be known until the EM charts for the F-35 become public anyway, which won't happen anytime soon.

Edited November 17, 2016 by Hummingbird

[Darkbrotherhood7]

Remember though , this is with 7G limit in place

 

Yeah I know, these are very good statistics if you consider the 7G limitation.

[Darkbrotherhood7]

It's clear when looking at the F-15 for reference that they're using an F-16 with wing bags for the comparison though as the F-16's STR is higher than that of the F-15 under most conditions.

Yeah, but don't you think it's fair? If you consider the 7G limitation?

 

 

The real truth wont be known until the EM charts for the F-35 become public, which won't happen anytime soon.

 

^^This!

 

The F-35 maneuverability does not need to be the best, it just need to be good enough in case of a dogfight, which IMO already is.

Edited November 17, 2016 by Darkbrotherhood7

[garrya]

*sigh*

 

garrya

Dont " sigh " with me unless you have actual number or calculation to prove your point. Remember that all our discussions regarding F-35 and F-16 are based on guesstimation of F-35 dynamic thrust and CL. Neither me or you have the exact figure at the moment

 

The CAT system is there to make sure the aircraft doesn't "over G", it doesn't limit the F-16 at high speed at all, it safeguards it.

 

No aircraft, and that includes the F-35, will be pulling much over 15 deg AoA at high speed. Do that and the wings come off.

 

The F-35's high AoA capability is only useful at relatively low speeds,

CAT was done to help prevent deep stall as the single rudder loses effectiveness at much higher AoA and the pitch onset rate was higher than anything ever seen before so they wanted to make sure the plane did not over rotate at high speeds. But at the same time , the AoA limit at high G also limit its maximum achievable ITR. And F-35 doesnt need much higher AoA than F-16 in this case. A slight 5 increased from 15 to 20 degrees AoA increase CL significantly.

And what happened with your opinion regard dogfight speed ?? just a few pages ago you said common dogfight speed is about Mach 0.5-0.6 , now you change your stand and low speed not important ?

 

and here the F-16 isn't really limited being able to pull around 26-30 deg AoA, which is more than enough to ensure a high lift induced ITR. Go beyond that AoA and lift generating parts of the aircraft start stalling, lowering the overall lift generated, despite wether or not the wings gain a marginal increase in CL.

the maximum 25.2 degrees limit is at 1 G , go to 5G and that limit decreased to 20 degrees. F-16 cant reach 30 degrees AoA without stalling

Edited November 17, 2016 by garrya

[Hummingbird]

Yeah, but don't you think it's fair? If you consider the 7G limitation?

 

Well it's pilots opinions which are never definite or particularly accurate (esp. not this early on), since we don't have any specifics such as load outs etc.

 

That doesn't make them any less interesting though. But I'm sure they will differ from this once it's in fully fletched service and being flown combat loaded regularly.

 

 

^^This!

 

The F-35 maneuverability does not need to be the best, it just need to be good enough in case of a dogfight, which IMO already is.

 

Yes that's the basic idea, which is just fine for the role it's intended to fill with US. It's going to be an exceptional strike aircraft I'm sure, better in this regard than any fighter before it.

 

It's the role as an interceptor in which I fear it might be found lacking, which itself only concerns me because of the fact that several countries will rely on it for this role. For the US military however it seems like a match made in heaven.

[Darkbrotherhood7]

It's the role as an interceptor in which I fear it might be found lacking, which itself only concerns me because of the fact that several countries will rely on it for this role. For the US military however it seems like a match made in heaven.

 

I kinda agree, however, the F-35A was created to replace the F-16C/D, and if countries such as Belgium are replacing the F-16s by F-35As, what's the problem? Just because the F-35 is a bit slower?

[Hummingbird]

garrya,

 

I sigh because you so often ignore what's being said and because you fixate on tiny phrases, pick them out, and then address them completely out of context.

 

But let me show you how high an ITR the F-16 can achieve at high speed despite its' CAT system in comparison to the F-15 which features no such system:

 

 

 

 

ITR @ Mach 0.8

F-16 = 19 deg/sec

F-15 = 19 deg/sec

 

Not a big difference is it? Infact pretty much nonexistant...

 

The differences you'll find are at lower speeds and even then they're so small it's not at all important, esp. considering the mind blowingly high STR of the F-16.

 

In short the CAT system is no limitation at high speeds other than making sure that the load limit isn't breached.

 

PS: The Mirage 2000 features a similar AoA limiter, yet it is most certainly no slouch in the ITR department either:

http://2.bp.blogspot.com/-eiImrT1REak/UW4c4oeGpvI/AAAAAAAACRg/zfu0jsNC-3A/s1600/Mirage+2000+at+15k.jpg