Thrust Vectoring

[nightsight971]

Please offer your opinions on why the F-35 was not given thrust vectoring.

I understand its main drawback is that its mainly useful at low speeds and leaves the aircraft in a low energy state, affecting kinematic performance.

My problem or question is, why not include thrust vectoring on ALL fighters or attack aircraft to assist in turning as tightly as humanly possible?

Is it weight? Is it wear and tear?

I think with thrust vectoring, the F-35 could have been the end all be all aircraft the USA wanted. If only to help it turn.

I'm definitely no aircraft designer, so I'm pretty sure Lockheed knows what they are doing.

I just see thrust vectoring making attack aircraft like the F-35, or even the beautiful A-10, very deadly.

 

[OPSSG]

Not sure how to add to this discussion. The correct answer for the F-35 program — is that this is not specified for the program of record. Let me share a quote by Lieutenant Colonel Dave “Chip” Berke was the "Fighter Pilot" podcast, where there was not a lot about the F-35 (except for during the "fast round" Q&A at the end of the pod-cast, from 1 hr 30 on) that is relevant to this discussion. Given Chip has flown on the F/A-18, F-16, F-22 and F-35 he was asked, ‘which fighter would you would go to war with?’ Without hesitation he said:

"The F-35, it's not even close. The Hornet and F-16 were awesome aeroplanes but that's a by-gone era. Those airplanes aren't even close. Raptor is incredible; best manoeuvring aeroplane, but the breadth of information, situational awareness and capacity of the F-35 there is nothing even close to the Lightning. The plane hasn't done well in the media of late - recently it's done a lot better - but anyone on the inside that knows that aeroplane, it is by-far the most capable combat airplane that's ever been built. I wouldn't even blink if you asked me what to go to war in, it's the F-35, it's not even close".​

What is the big difference between the F-22 and F-35 in regards to sensor fusion:

"The biggest difference is the F-35 is fusing radio frequency, electro-optical, infrared and laser. The F-22 is RF only - basically just the radar. So it's the breadth of information and the spectrum out there the F-35 is way, way broader and deeper than the Raptor"​

My guess is that the F-35 designers are aware of the need to design to program spec, especially since the advent of helmet mounted sights to fire air-to-air missiles, sensor fusion, and the tactics related to modern beyond-visual-range combat. Design to spec is important in cost management for any new fighter program.

Frankly, I am astounded by your post, as it seems to focus on a limited low speed flight profile (aka thrust vectoring) that is tactically not as useful when compared to other key specified features for 7G to 9G capable 5th and 4.5 gen fighters.

Keep in mind that missiles like the ASTER are far more capable of tight turns at high speed (at supersonic speeds) and MBDA’s Meteor beyond-visual-range air-to-air missile that can throttle its engine during different phases of flight, that can black-out any pilot, even in modern g-suits. Not only does this mean the Meteor will have more energy to maneuver during the endgame of the engagement, but this capability also drastically increases the size of the missile’s “no escape zone.” Basically, the Meteor has a far greater ability to “chase” and catch enemy aircraft over long beyond visual range (like the AIM-54 Phoenix). Modern beyond-visual-range combat (with the AMRAAM and the Meteor) don't make dog fighting obsolete, they just make it less likely. With off-bore-sight, high agility missiles, dog fighting becomes much more lethal for everyone. Weapons like these become equalizers between highly maneuverable aircraft and less maneuverable competitors. While the high maneuverability found in the thrust vectoring engines is interesting — it is simply not as decisive as it once was.

I hope others will take the time to explain more than I have said here.

 

[Todjaeger]

Please offer your opinions on why the F-35 was not given thrust vectoring.

I understand its main drawback is that its mainly useful at low speeds and leaves the aircraft in a low energy state, affecting kinematic performance.

My problem or question is, why not include thrust vectoring on ALL fighters or attack aircraft to assist in turning as tightly as humanly possible?

Is it weight? Is it wear and tear?

I think with thrust vectoring, the F-35 could have been the end all be all aircraft the USA wanted. If only to help it turn.

I'm definitely no aircraft designer, so I'm pretty sure Lockheed knows what they are doing.

I just see thrust vectoring making attack aircraft like the F-35, or even the beautiful A-10, very deadly.

A short, quick answer is that thrust vectoring is not as useful a capability as others to have aboard a modern fighter aircraft.

A somewhat more involved and lengthy explanation is that while thrust vectoring can improve the maneuverability of a modern fighter, the degree of importance the kinematics (essentially speed and maneuverability) of modern fighters has is less important, much less than it used to be.

There are a few reasons why there has been this decrease in the kinematic performance of fighters. One has to due with the changing nature of warfare, and the other changes to the capabilities of weapons (surface & air-to-air missiles specifically) used. A prime example of that is that the best a modern fighter can manage, with a healthy pilot using a modern g-suit, is ~11g's before the pilot will either black or red out. 11g maneuvering, while good, is not going to be equal to a 40g to 60g WVR or BVR air-to-air missile or a SAM. Additionally (and this has to do with changes in the nature of warfare) dogfights should largely be a thing of the past, with air to air engagements largely occurring at BVR ranges and therefore fighters should have little need to maneuver in a dogfight to get into a shooting position. Even if for some reason hostile aircraft were engaged at WVR (likely due to ROE's requiring a visual ID/confirmation) using modern avionics, pilot helmets and HOB (high off-bore) sight and/or LOAL (lock-on after launch) missiles, the positioning or approach vector of an engaging fighter is less important than it used to be. In the past the nose cone of a fighter needed to basically be pointed in the basic direction of the target being engaged in order to achieve a lock or launch missiles. This has now (for some fighters at least) become a thing of the past.

In terms of air to air warfare, a major change has been the importance of achieving informational superiority, particularly in the area of SA (situational awareness). This has replaced older requirements to be faster and/or more maneuverable than hostile aircraft and this makes a great deal of sense when one considers the implications of Fighter A being able to detect or otherwise be aware of Fighter B, at a time when Fighter B is completely oblivious to Fighter A. The basic maxim being, "he who sees first, shoots first, he who shoots first, wins." In the above situation, Fighter A has the potential to set the terms of the engagement with Fighter B, due to having earlier awareness to the presence of Fighter B. Potential options for Fighter A range from choosing the optimal position to be in to engage Fighter B, to launching air-to-air missiles from within the NEZ and possibly before Fighter B becomes aware that he has been detected.

With all that in mind, it does not make much sense to spend resources developing a thrust vectoring system for aircraft that, if operated properly, should not find themselves in a situation where thrust vectoring would be useful or make a difference in the outcome.

 

[the concerned]

To be honest the only useful place thrust vectoring maybe applied is future ucavs. This is just my opinion and not fact but the most useful thing in engine capabilities is to be able to take off with a useful load without the need of afterburner.

 

[John Fedup]

The other place is air shows.

 

[ngatimozart]

@Todjaeger I'd be somewhat hesitant to claim that the end is nigh for dogfighting. That was claimed in the late 1950s and 1960s by a plethora of missile disciples within the USAF, USN and the wider US defence establishment, but the North Vietnamese Peoples Air Force soon showed them the error of their ways. The US is repeating the same mistake and note that new European, Russian & Chinese fighter types still carry guns as well as missiles. When you go Winchester with your missiles and have no guns, what do you have left??? Just because you have missiles that can reach out and touch an enemy BVR or WVR beyond gun range, does not mean that you may not end up getting up close and personal whether you like it or not. Infantry have personal weapons that can reach our 300 - 600+ metres, yet still carry a bayonet and / or knife for up close personnel work and train for it. My point is that you have no guarantee that you will be able to dictate the circumstances of a furball and any subsequent dogfight. The enemy are not going to fight according to your rules and what you've planned for. To assume such is arrogant and stupid.

The second point you make about informational superiority is only correct if you have achieved air superiority AND EW superiority. If you haven't then you are in trouble. The US hasn't fought against a peer level enemy since WW2 / Korea. Since 1991 it's achieved air superiority in all theatres that it has operated in because of limited or no air opposition, and in the first war against Iraq, unleashed a new concept in air war against arguably the best IADS in the world at the time. Today against a peer such as China or Russia, but especially China, without going nuclear, it would seriously struggle and the probability of failure would be medium to high.

 

[Feanor]

arguably the best IADS in the world at the time

I think this is dead wrong. The best IADS in the world at that time was the Soviet one. Even on a basic platform level, the Soviets had far more GBAD, had far greater strategic depth (making it harder to strike many of the deeper targets), and had more advanced systems then anything the Iraqis had (the S-300 entered service in 1979 and by 1991 well over a hundred btlns were in service). More importantly, sitting there for two weeks and trying to roll back GBAD and win air superiority wouldn't have been an option against the Soviets, since they certainly would have moved on the ground, or possibly even gone nuclear. The Iraqis were second rate at best compared to this.

A short, quick answer is that thrust vectoring is not as useful a capability as others to have aboard a modern fighter aircraft.

I think this is a very strong statement and it raises questions such as why the F-22 has thrust vectoring? Or the Su-35S?

EDIT: Vis-a-vis the first paragraph above - the best GBAD-centric IADS.

 

[John Fedup]

Possibly the F-35 doesn't have it as the USAF decided it wasn't worth the cost based on F-22 experience, just a guess. BTW, does the Su-57 retain thrust vectoring?

 

[Feanor]

Possibly the F-35 doesn't have it as the USAF decided it wasn't worth the cost based on F-22 experience, just a guess. BTW, does the Su-57 retain thrust vectoring?

Yes it does. It carries engines that are currently very, very similar to what the Su-35S carries.

 

[StobieWan]

Please offer your opinions on why the F-35 was not given thrust vectoring.

I understand its main drawback is that its mainly useful at low speeds and leaves the aircraft in a low energy state, affecting kinematic performance.

My problem or question is, why not include thrust vectoring on ALL fighters or attack aircraft to assist in turning as tightly as humanly possible?

Is it weight? Is it wear and tear?

I think with thrust vectoring, the F-35 could have been the end all be all aircraft the USA wanted. If only to help it turn.

I'm definitely no aircraft designer, so I'm pretty sure Lockheed knows what they are doing.

I just see thrust vectoring making attack aircraft like the F-35, or even the beautiful A-10, very deadly.

Easier and cheaper to put the thrust vectoring onto the missile the aircraft is firing and not worry about integrating it into the launch platform. TV adds weight, complexity and gives some small advantage in an area of combat which really should be avoided at all costs - ie, a low speed knife fight in which both adversaries will likely end up dying to the other guys missile.

Sticking TVC on the A10 would have to rank as one of the worst ideas I've heard mind you - they don't have a whole lot of thrust in the first place and they're usually regarded as being very manoeuvrable *once* then they're out of energy and making leaf impressions.

If you're carrying missiles that can attack targets at very large angles off boresight I'd say WVR combat is something you'd want to avoid at all costs and the weight taken by TVC can be better allocated to counter measures or fuel.

 

[nightsight971]

The addition of the A10 in my thrust vectoring post was simply about giving a ground attack aircraft the ability to more quickly whip around for another strike.

 

[Todjaeger]

Ng I will respond more fully to you later one, when I have a bit more time since there are a couple of things which I disagree with in your post. However, it does seem that part of my post was misunderstood since I do not think, "the end is nigh" for dogfights as there are circumstances when it might still happen. However, it is not a situation which would happen by choice normally.

I think this is a very strong statement and it raises questions such as why the F-22 has thrust vectoring? Or the Su-35S?

Consider the long and at times torturously convoluted development programme that led to the F-22. It started with a RFI for the ATF programme in 1981... The first flight of an F-22 was itself in 1997. I strongly suspect some of what was included in the design was included because at the time of the inclusions, the conops at the time would have had thrust vectoring as something valuable. Now because of advances in both avionics and missiles, it really does not matter so much for aircraft.

The addition of the A10 in my thrust vectoring post was simply about giving a ground attack aircraft the ability to more quickly whip around for another strike.

Nothing simple about fitting thrust vectoring to an already in service airframe and engine combo that was not designed for that. As for the value in being able to rapidly re-position to strike again... Unless one is talking about using the main gun, the actual nose position of an A-10 is not so important unless one is using dumb ordnance. If one is using dumb ordnance, then why bother spending the significant funding requiring to backfit thrust vectoring onto a subsonic attack aircraft.

 

[StobieWan]

The addition of the A10 in my thrust vectoring post was simply about giving a ground attack aircraft the ability to more quickly whip around for another strike.

No need, in a near peer environment, it'd be dead the moment it'd be detected so worrying about coming around for another strike is redundant.

If you're going to war with a bunch of blokes wearing flip flops and carrying AK's, take your time, they're dead anyway.

Either way, my point stands, adding TVC takes away weight you could allocate to more weapons, fuel or counter measures.

It's also another point of failure in the event a MANPAADS manages to score a hit.

 

[Todjaeger]

In an effort to further hammer home the declining importance of kinematic performance in modern fighters, the air superiority variant F-15C Eagle has a listed max speed at high altitude of Mach 2.5, while the F-22 which is replacing the F-15C in the air superiority role has a listed max speed of Mach 2 at altitude. A similar situation exists for the F-35 when comparing max speeds with legacy fighters that will be replaced with the F-35.

If these specific capabilities were so important, then they would have been included as part of the design criteria. Since they were not, then the relative value for some of the older capabilities one can fairly safely assume has diminished.

 

[Boagrius]

In an effort to further hammer home the declining importance of kinematic performance in modern fighters, the air superiority variant F-15C Eagle has a listed max speed at high altitude of Mach 2.5, while the F-22 which is replacing the F-15C in the air superiority role has a listed max speed of Mach 2 at altitude. A similar situation exists for the F-35 when comparing max speeds with legacy fighters that will be replaced with the F-35.

If these specific capabilities were so important, then they would have been included as part of the design criteria. Since they were not, then the relative value for some of the older capabilities one can fairly safely assume has diminished.

I'd expand on this a little to say that - particularly in the US - there has been a shift in focus to certain parts of the flight envelope as far as kinematic capability is concerned. Both the F22 and F35 are designed to perform best at certain operationally representative speeds, altitudes, AoAs etc. Neither is meant to operate at its top speed much if ever - they are combat aircraft after all, not drag racers.

Take the within visual range (WVR) domain as an example. My understanding is that the US approach places an emphasis on killing as many enemy aircraft as possible before a merge happens (if one happens at all). Ideally this results in a WVR fight that favours the friendly side in terms of the energy state of the aircraft involved as well as in terms of raw numbers. This is reflected in the design of both the F22 and F35 - they are aircraft that are well tailored to not just BVR combat in general, but killing before the merge occurs (WVR engagements do not always necessitate dogfights). In the F35's case it also has the option of using AN/AAQ37 to cue AAMs in any direction without anchoring into a prolonged turning fight and bleeding precious energy in the process. This - ideally - also allows it to exit the fight as needed.

To me this makes a lot of sense, since the quality of modern short range AAMs has become, frankly, incredible. We now have SRMs with imaging IR seekerheads that should for all intents and purposes be immune to most (if not all) IR countermeasures, along with high off-bore-sight and lock-on-after-launch capabilities that make it possible to fire them at a target in literally any direction. When you consider the fact that these have been mated to thrust vectoring, 60g+ missiles you have a situation where closing to within ~5nm of enemy aircraft is a very poor method of obtaining favourable kill ratios for everyone.

With that said, I can see how changing threat environments may dictate a shift to more "powerful" aerodynamic performers. For example, I expect the evolution of PLAAF strategic airpower coupled with the tyranny of distance inherent to the Pacific theatre to drive a move towards faster, larger and longer ranged aircraft when the likes of PCA/NGAD eventuate. I wouldn't necessarily expect TVC to be a central feature of such aircraft, as I imagine things like fuel and weapons load capacity, sensor capabilities, data sharing, signature reduction and EW capabilities would take precedence.

 

[Todjaeger]

The second point you make about informational superiority is only correct if you have achieved air superiority AND EW superiority. If you haven't then you are in trouble. The US hasn't fought against a peer level enemy since WW2 / Korea. Since 1991 it's achieved air superiority in all theatres that it has operated in because of limited or no air opposition, and in the first war against Iraq, unleashed a new concept in air war against arguably the best IADS in the world at the time. Today against a peer such as China or Russia, but especially China, without going nuclear, it would seriously struggle and the probability of failure would be medium to high.

From my perspective, not really. At an asset level, informational superiority can simply mean that the asset is aware of the presence and/or location of a hostile first (due to onboard sensors, datalink, ESM, whatever since the method is not important for the example) and/or the asset is more difficult for hostiles to detect and track (due to LO features, EMCOMM, EW, jamming, again whatever). It is again a continuation of the maxim that he who sees first, shoots first and he who shoots first usually wins.

In the examples, thrust vectoring does nothing to either increase the ability of a fighter to 'see' potential hostiles earlier or from farther away, nor does thrust vectoring do anything to make a fighter harder to be 'seen' by hostile air, ground or naval forces.

 

[nightsight971]

Nothing simple about fitting thrust vectoring to an already in service airframe and engine combo that was not designed for that.

Sorry for the confusion, no way do you retrofit a plane now. But its replacement? With the F35 taking over for the A10 soon it makes sense for it be able to turn on a dime. Then you would have better jack of all trades aircraft for all the branches.

But your arguments are all great. From what I've read Thrust Vectoring is costly and heavy. I just cant overrate giving a military aircraft the ability to turn as much as the human inside can take.

 

[Todjaeger]

Nothing simple about fitting thrust vectoring to an already in service airframe and engine combo that was not designed for that.

Sorry for the confusion, no way do you
retrofit a plane now. But its replacement? With the F35 taking over for the A10 soon it makes sense for it be able to turn on a dime. Then you would have better jack of all trades aircraft for all the branches.

But your arguments are all great. From what I've read Thrust Vectoring is costly and heavy. I just cant overrate giving a military aircraft the ability to turn as much as the human inside can take.

Increasing the ability of a fighter to turn (especially at low speeds) ignores the whole issue of why the fighter would need to turn, as well as when it might be advantageous to be able to turn faster and/or tighter.

Using the example given of F-35 being expected to replace the A-10 in ground attack/CAS roles, that is the expectation, AFAIK however, the F-35 would not be operated in the same manner as an A-10 even when performing the same role. I really doubt that most air forces would be keen to have pilots flying new fighters into potential trashfire range just so they can be engaged by the on board 25 mm gun. That strikes me as a good way to lose an F-35 operationally. If the F-35 were to provide CAS from above the range of manpads and light AA guns, then missiles or bombs would be used for air support.

 

[Boagrius]

But your arguments are all great. From what I've read Thrust Vectoring is costly and heavy. I just cant overrate giving a military aircraft the ability to turn as much as the human inside can take.

AFAIK the F35A can already turn as much as the human inside can take - it is a 9G aircraft. I'm not sure that fitting it with TVC would change this much. Perhaps it would allow for more G in some parts of the flight envelope - I genuinely don't know.

As for the A10, it is much more G limited due to the design of the airframe. Attempt to pull +9Gs in a combat loaded Hog and you run a serious risk of damaging/ripping off the wings.

 

[StobieWan]

Nothing simple about fitting thrust vectoring to an already in service airframe and engine combo that was not designed for that.

Sorry for the confusion, no way do you retrofit a plane now. But its replacement? With the F35 taking over for the A10 soon it makes sense for it be able to turn on a dime. Then you would have better jack of all trades aircraft for all the branches.

But your arguments are all great. From what I've read Thrust Vectoring is costly and heavy. I just cant overrate giving a military aircraft the ability to turn as much as the human inside can take.

There's no way in any combat aircraft you'd ever want to make a second pass in a high threat environment - ideally, you don't even make the first pass - you launch some distance away. But, if you did have to make a pass over or running parallel to the target, you keep going, get over the horizon and re-attack from another angle entirely.

The only environment you can start looking at circling over head is when the competition is driving a Hi-Lux with a Dushka bolted to the back as I've mentioned.


The F35 is already capable of pushing the human physique well outside its envelope - the A has already been tested beyond 9Gs for instance. Certainly if you read some of the reports from COPE India of WVR combat vs the IAF, the main reports about TVC all relate to how the aircraft just starts to fall over as you get into that regime and presents an easy gun kill.

I think you're trying to solve a problem that's already been addressed by off loading the required capability to the weapon.