The role and suitability of STOVL aircraft in the modern battlefield

[SOC]

Re: STOVL Discussion

So the A-10 is awesome, but its not invincible.

Blasphemy! Media-overhyped IADS #3285 managed to basically blow half of one off during DESERT STORM. At which point it simply RTB'd, leading to a discussion of whether the heavy spheroids dangling below the airframe belonged to the pilot, or actually to the aircraft.

I vote for the aircraft ;D

In seriousness, if the A-10 wasn't technically invincible, it certainly did set a new standard for battlefield survivability. On that note, is the lift fan for the F-35B given any sort of shielding? I'd wonder what happens when you have to send in a few F-35Bs to perform CAS and a few lucky AAA rounds pop off near the lift fan.

 

[LowObservable]

Good question on survivability, SOC.

I must say that I wondered about the gas-driven lift fan that was the early alternative to the F-35B approach. A lot of hot knitting (as John Fozard used to call it) and if you'd had anything burst near you, no way to tell it it was punctured until you selected VL mode, at which point 1000-degree-plus gas would squirt out through any holes.

The SDLF is a little better off insofar as the critical components are smaller in area and shielded by other structure, but there's still a lot of surface area (doors, for example) where everything has to work properly for VL, and the single engine has to be capable of delivering full power.

 

[aam641]

As to survivability, I was wondering how much altitude F-35B needs to transition to forward flight if the lift fan starts to fail. Anybody knows?


I was watching Die Hard 4 yesterday. F-35B in the film sucked in a couple of large rocks into the fan and kept flying for another minute or so. Hollywood fiction aside, it would seem to me that if the lift fan looses even 20% of thrust, the plane will pitch ass over head and go straight to the ground.

 

[TaiidanTomcat]

Great point with the A-10! Other than losing 6 of them in Desert Storm, having others damaged beyond repair and out of the fight and scrapped multiple times since, the combat restrictions, along with the fact that its so slow the pilots carry calenders instead of wrist watches, The A-10 is truly irreplaceable. Its anecdotal I know, but I know an A-10 pilot and she is doing everything she can to pass her physical and get into the F-35. She loves to tell me how the A-10 is great, but far far from invincible and she knows it.

Its funny that in a debate that talks about how STOVL may be so compromising in aircraft that it essentially makes them specialist, that the A-10 the most compromised specialized aircraft of them all, is deemed "too awesome!!"

 

[AeroFranz]

The compromise I refer to relates to the ability of the platform to perform its mission. In the case of the F-35B, the extraneous weight deriving from its VSTOL capability detracts from its raison d'etre, which is to carry bombs over a distance.
In the case of the A-10, the designers were unencumbered by such penalties. So it is a specialized aircraft, but arguably not mission-compromised.

Specialization is not necessarily a bad thing provided the mission is positively, absolutely necessary, and you are not using resources that could be better spent on something else that might enhance your overall fighting capability. My .02.

 

[SOC]

STOVL is compromising. For that matter, so is LO, or carrier compatibility, or a number of other design considerations you can point to. At that point you have to decide if the compromise is worth the expected performance.

Right now? I'd argue that it's the LO design that's the bigger problem than the STOVL capability. An accurate, 3D VHF-band radar will take your fighter-sized airframe's LO capability right out of the game. It's called "physics". It runs everything, and is not able to be conveniently ignored. Despite what...well, I'm not going there B) So by designing one now (the F-22 was a cold-war product designed when such things weren't becoming more and more commonplace), you're basically admitting that the politicians are eminently full of crap and Russia/China are not military threats, meaning you intend only to use a rather expensive aircraft to bomb third-world countries. Which in most cases amounts to overkill and is arguably an example of severe financial misconduct.

STOVL only really matters if you think there will be a conflict in the future that 1) the USAF is out of, meaning that you've got no friendly basing close enough to the theater, and/or 2) the USN does not see fit to grace with a CVBG's presence. At which point, you're back to it being a likely case of overkill versus the threat that would result in 1 or 2. That doesn't mean that the jet doesn't work, just that, well, where are you going to run into a situation where you absolutely cannot get by without having it? If you can't find such a situation, then again, you're wasting money. Plus, if you're going to use a survivable B-2 or a comparatively survivable F-22 (speed/altitude vs. the F-35) or a swarm of TLAMs to kick down the IADS, you've once again negated the need for the LO aspect of the airframe.

And to the STOVL capability imposing a weight penalty detracting from range...well, it sounds good on paper, but combat radius is one of the most asinine statistics out there. In an actual combat environment, assets are constantly hitting tankers to retain relatively full fuel tanks for various reasons (fuel to maneuver, fuel to reach alternate recovery sites in the case of various contingencies, fuel for orbiting over a combat zone, etc). Which goes and makes the whole combat radius figure a little bit irrelevant. Yes, a shorter radius technically means more tanker support, but the last time a strike package had to use tankers to really cover a long distance to the point where a shorter radius would've had a serious impact was over Libya. In 1986, not 2011.

 

[tacitblue]

Oh man, now we're defending the A-10. The Warthog was born in the 1970s before anyone knew anything about LO, and before anyone knew that there would be a way to counter air defenses other than support jammer aircraft and the infamous Wild Weasles (otherwise known as an expense to build, maintain, train drivers and maintainers, and operate). The -35 may cost more per airframe than an A-10 (but remember that was almost 40 years ago when the program began), but the -35 does not need support aircraft. Dollar for dollar, the -35s LO and being able to operate without dozens of support aircraft leads one to conclude that -35 is more cost effective and yields a leaner military with more teeth and less tail. Not too mention in a battle there will be less aircraft to maintain, refuel, turn around. . . . Do any of the -35 detractors get the idea?
The Harrier is garbage. We've lost about 25% of the fleet due to their love of diving into the ground as normal operating procedure.
The need for STOVL is basically built into the Marines because of their small boats. There's no getting around that unless we can find $100b under the Congressional doormat to build the Marines some bigger boats.

 

[sferrin]

STOVL is compromising. For that matter, so is LO, or carrier compatibility, or a number of other design considerations you can point to. At that point you have to decide if the compromise is worth the expected performance.

Right now? I'd argue that it's the LO design that's the bigger problem than the STOVL capability. An accurate, 3D VHF-band radar will take your fighter-sized airframe's LO capability right out of the game. It's called "physics". It runs everything, and is not able to be conveniently ignored. Despite what...well, I'm not going there B) So by designing one now (the F-22 was a cold-war product designed when such things weren't becoming more and more commonplace), you're basically admitting that the politicians are eminently full of crap and Russia/China are not military threats, meaning you intend only to use a rather expensive aircraft to bomb third-world countries. Which in most cases amounts to overkill and is arguably an example of severe financial misconduct.

STOVL only really matters if you think there will be a conflict in the future that 1) the USAF is out of, meaning that you've got no friendly basing close enough to the theater, and/or 2) the USN does not see fit to grace with a CVBG's presence. At which point, you're back to it being a likely case of overkill versus the threat that would result in 1 or 2. That doesn't mean that the jet doesn't work, just that, well, where are you going to run into a situation where you absolutely cannot get by without having it? If you can't find such a situation, then again, you're wasting money. Plus, if you're going to use a survivable B-2 or a comparatively survivable F-22 (speed/altitude vs. the F-35) or a swarm of TLAMs to kick down the IADS, you've once again negated the need for the LO aspect of the airframe.

And to the STOVL capability imposing a weight penalty detracting from range...well, it sounds good on paper, but combat radius is one of the most asinine statistics out there. In an actual combat environment, assets are constantly hitting tankers to retain relatively full fuel tanks for various reasons (fuel to maneuver, fuel to reach alternate recovery sites in the case of various contingencies, fuel for orbiting over a combat zone, etc). Which goes and makes the whole combat radius figure a little bit irrelevant. Yes, a shorter radius technically means more tanker support, but the last time a strike package had to use tankers to really cover a long distance to the point where a shorter radius would've had a serious impact was over Libya. In 1986, not 2011.

To suggest stealth is useless is a bit of a stretch wouldn't you say? Call me crazy but I'd think well, just about everybody working on stealth has considered your point there. It doesn't seem to have caused anybody to back off. In fact if anything more countries are clamoring to jump on the stealth bandwagon.

 

[TaiidanTomcat]

The compromise I refer to relates to the ability of the platform to perform its mission. In the case of the F-35B, the extraneous weight deriving from its VSTOL capability detracts from its raison d'etre, which is to carry bombs over a distance.

But of course since the Lift Fan weighs less than the fuel the other two variants carry the F-35B is actually the fastest variant save the F-35A when it is at 50% percent or below. Amongst fully loaded F-35s, the Fully loaded F-35B is the lightest variant. that lift fan is such a red herring. The Naval version is the most heavy of course. The F-35C has the most range, but is low in speed compared to the other versions. Even with "less range" The F-35B is still nearly 1000KM with an internal load! well above legacy platforms. The only aircraft that beat it are other F-35 variants! Which aint bad in my book.

ALL NAVAIR aircraft have compromises built in too:

*Extra fuel must be carried at all times in order to attempt four landings.
*More training time dedicated to landing (ask a USAF pilot about "navy landing practice")
*increased structure weight to handle Cats and TRaps
*Heavier undercarriage
*Strict Perimeters in order to safely land at low speeds aboard a ship
*Heavier tail hook
*Severe airframe abuse and limited use due to the violence naval aircraft endure daily, drastically shortening the Airframes service life
*More necessary inspections as well to find cracks.
*increased maintence
*increased cost

Naval aircraft are some of the most compromised aircraft in the world. Designs always revolve around its ability to take off and land safely aboard ship, which (I don't think anyone will argue with me on this) is freaking difficult on a good day.

In the case of the A-10, the designers were unencumbered by such penalties. So it is a specialized aircraft, but arguably not mission-compromised.

Thats my point they compromised in every mission except its primary mission-- thus its compromised to do one thing and one thing only. I would also say it IS mission compromised since it can not go into certain environments that are considered too dangerous. In which case it is not mission compromised at all-- providing its even allowed to safely perform its mission in the first place. What good is a specialist aircraft that can't fight?

Compare to the F-35 which will do a myriad of missions to include the A-10's. And before the "the A-10 is the only CAS weapon evah" argument -- if it wasn't good at CAS, Why in the hell would the Marines want the F-35? Everything the Marine Corps does is to support the Rifleman Marine on the ground. If it won't do CAS the USMC doesn't want it.

 

[SOC]

Oh man, now we're defending the A-10.

My point, at least, was largely sarcasm intended to lead into the survivability question. Although I can break out the A-10 AwesomenessTM card if I want to, I had a family member commanding a Warthog squadron someplace hot and sandy in 1991

The -35 may cost more per airframe than an A-10 (but remember that was almost 40 years ago when the program began), but the -35 does not need support aircraft. Dollar for dollar, the -35s LO and being able to operate without dozens of support aircraft leads one to conclude that -35 is more cost effective and yields a leaner military with more teeth and less tail. Not too mention in a battle there will be less aircraft to maintain, refuel, turn around. . . . Do any of the -35 detractors get the idea?

Except support aircraft such as SEAD/DEAD platforms, tankers, jammers, etc. are often used to support LO platforms regardless. "It can do X" is often different from "we use it in fashion Y". And once you start putting weapons on external attachment points at that stage in the game you'll have those support assets still around just in case anyway. Now, the way to get around this to an extent is to use other F-35s, or F-22s, as SEAD/DEAD platforms to whack IADS components while others strike targets. But in that case you either 1) draw out the conflict as you'll do the IADS and then the targets, meaning you need more sorties overall and drive up your costs, or 2) use more airframes, eating into the advertised advantage you think you had. It's not that the F-35 will be useless, part of the problem is that the figures like "X aircraft to hit Y targets" or "combat radius of Z kilometers" often don't reflect the reality of actual combat operations, at least in my experience in the USAF.

To suggest stealth is useless is a bit of a stretch wouldn't you say? Call me crazy but I'd think well, just about everybody working on stealth has considered your point there. It doesn't seem to have caused anybody to back off. In fact if anything more countries are clamoring to jump on the stealth bandwagon.

For an air superiority fighter, it makes sense from certain aspects. The wavelengths you'll be the "stealthiest" against are those of other fire control radars. That gives you first shot capability. But if you're facing a modern IADS, which we've never done but we might get to see pieces of one over Syria, the advantages you've got can be seriously reduced unless you're big enough to be LO in the VHF band, like the B-2. But if the intent is to continue only bombing third-world states without the common sense to upgrade their IADS after we consistently 1) make the media touting other supposedly advanced and awesome networks look remarkably stupid, and 2) completely devastate IADS built on seriously aged Soviet-era technology, then LO is going to give you a significant edge, sure. And again, when the F-22 and F-35 were conceived, digital VHF-band radars capable of doing anything remotely competent weren't 1) widely deployed or 2) widely marketed for export.

 

[tacitblue]

But if the intent is to continue only bombing third-world states

If you consider global politics, then yes, we're only ever going to continue bombing third world nation states. None of the superpowers are ever going to have a shooting war, considering how embedded all of our economies are. Russia is basically run by the mob, who are money hungry, and China's economy is too reliant on the US economy.

 

[GTX]

and China's economy is too reliant on the US economy.

And the US (and others in the West are too reliant on what China provides.

 

[Evil Flower]

We had a very integrated world economy in 1914 and that sure didn't stop the big powers from going to war.

 

[tacitblue]

We had a very integrated world economy in 1914 and that sure didn't stop the big powers from going to war.

No where even close to what it is today... Not even close by a light year. In 1914 the world was still transitioning into an industrial world (read "The Third Wave"). What I said stands and is without flaws: Russia is run by the Mafia, and China would crumble from within if there were a shooting match with the US/Europe. The US consumers would suffer, but we can live without Nike shoes, DVRs, IPADs, and yatta yatta yatta. Even so, it would be a boon to the US as production of those products would return to the US, so war with China would actually be a good thing (long run) for the US.

 

[GTX]

The US consumers would suffer, but we can live without Nike shoes, DVRs, IPADs, and yatta yatta yatta. Even so, it would be a boon to the US as production of those products would return to the US, so war with China would actually be a good thing (long run) for the US.

I admire your optimism regarding the typical consumer, though I personally doubt it would be that easy. As for production returning to the US and a war between China and the US being a good thing ... :

 

[Evil Flower]

Well the elite who own the military/industrial/banking complexes of the world will profit from it so for them it'd be a good thing.

 

[NUSNA_Moebius]

Compare to the F-35 which will do a myriad of missions to include the A-10's. And before the "the A-10 is the only CAS weapon evah" argument -- if it wasn't good at CAS, Why in the hell would the Marines want the F-35? Everything the Marine Corps does is to support the Rifleman Marine on the ground. If it won't do CAS the USMC doesn't want it.

Cost per capability (at CAS), low level and speed maneuverability, and damage absorption is I'm sure is far in favor of the A-10, but the A-10 can't be deployed off carriers, and the cost of creating a dedicated STOVL CAS aircraft would of course be quite expensive and difficult. I also consider the A-10 & F-16 close air support conundrum chronicled in Bill Gunston's Great Book of Modern Warplanes (ISBN 0-517-63367-1):

The A-10 is not a high-g, high-powered aircraft, the one thing that it can do better than any supersonic fighter is turn at low speeds. A fighter like the F-16 is designed to catch a victim or lose an attacker in a turn, and does it with the brute power installed in the lightest possible airframe. Low speeds represent a loss of energy, and are avoided at all costs. The A-10 is different in concept. Low turning airspeeds are accepted because air combat capability is not required. Because the airspeed is low, the A-10 can attain a high rate of turn, in degrees/sec, without the high g forces that would be associated with the same rate at higher speeds. Low airspeed and high turn rate combine to give a small turning radius; the first lesson in geometry states that the circumference of the turn, the distance which the aircraft actually travels, is smaller too. The aircraft will therefore take less time to complete it's turn.

Translating theory into fact, it is paradoxical but true that the A-10 will out-turn even an F-16 in full afterburner when the two aircraft are carrying similar loads. At 320kt (590km/h) and 3.5g, the A-10 can complete a half-turn, radius 2,700ft (824m), in 16 seconds. The F-16, at 600 kt (1,110km/h) and 6g, makes a 3,620ft (1,043m) turn, and takes 17 seconds.

Another quote from a diagram description and associated data within it:

From target recognition to Maverick launch takes the same time during which the fast-mover gets much closer to the target and it's associated defensive systems:

Non-afterburning F-16: 600kt, 3.5g turn - 9,500 ft turn radius, time (recognition, lock, and fire + egress) = x (recognition to launch) + 29 sec (180° turn)

Afterburning F-16: 600kt, 3.5g turn - 5,390 ft turn radius, time = x + 17 sec

A-10: 320kt, 3.5g turn - 2,700 ft turn radius, time = x + 16 sec

The F-35B is pretty impressive considering it's list of things it can do and aircraft it is effectively replacing, but a dedicated aircraft can be built with no compromises for other missions, hence why so many are so tentative about losing the A-10. I myself am a firm believer in that there is no replacement for the A-10 accept new built A-10s or an aircraft derived from it. The F-35 won't be able to get as low and slow

Only semi-reasonable idea in my head would be a more advanced Scaled Composites/Rutan ARES with perhaps two crew members, some more electronics like FLIR, more powerful and higher bypass turbofan engine, as well as more comprehensive high lift devices with the helicopter carrier being equipped with ski-ramps and arresting gear so it can operate directly with F-35s and forward airfields. It would be an inbetween of the OV-10 and A-10. Going bigger just gets more expensive REAL quick, and still the Rutan ARES, as cool as it is would be a bit moot in the USMC vertical style mission with a tiltrotor attack aircraft considering the modifications and risks involved with operating a fixed wing on an LHD. However a tiltrotor attack system would be pricey and risky.

 

[GTX]

The F-35B is pretty impressive considering it's list of things it can do and aircraft it is effectively replacing, but a dedicated aircraft can be built with no compromises for other missions, hence why so many are so tentative about losing the A-10. I myself am a firm believer in that there is no replacement for the A-10 accept new built A-10s or an aircraft derived from it. The F-35 won't be able to get as low and slow

The days of dedicated, single mission platforms went out decades ago...economic realities finally came home.


As for doing things the way we used, well if we take that position we should all still be flying open cockpit canvas and wood biplanes...

 

[LowObservable]

The days of dedicated, single mission platforms went out decades ago...economic realities finally came home.

The cost of creating a dedicated STOVL CAS aircraft would of course be quite expensive and difficult.

It's interesting to find these orthodoxies still accepted without qualification. A STOVL supersonic stealth fighter has indeed been expensive and difficult to develop. But those costs have been added to, and camouflaged by, the still larger cost of a tri-service program.

A non-STOVL JSF would not have needed a new engine, because two F414s would have done the job at less cost and at lower weight (by 2000 pounds). The CDA exercise would not have been needed. The SWAT exercise would have been unnecessary. Those STOVL-unique costs amount to $17 billion, before you even figure in STOVL-unique flight test and flight systems development.

The scar weight and cost of the heavy, expensive engine penalizes every A and C model in production. And to the degree that engine first cost drives maintenance costs, it increases operating costs.

Would the total lifecycle cost of a CTOL/CV program plus a dedicated LH-compatible CAS have been greater? Depends on the CAS spec and whether the Marines really need stealth and supersonic (and how much you really want to pay for those attributes). Indeed, you could argue from a Marine viewpoint that the joint requirement raised the cost of the STOVL aircraft.

The more important point is that the wildly optimistic cost estimates at the start of the program prevented the question in the previous paragraph from being raised or intelligently debated.

 

[GTX]

It's interesting to find these orthodoxies still accepted without qualification.

Nope...based upon years of experience with multiple programs...American, European, Australian, Asian and Multinational.


And stop trying to turn this into yet another anti-JSF crusade - there is a dedicated thread that you can carry that out in!

 

[AeroFranz]

The 'no holds barred one'? I hope we can remain polite and discuss this over here, since the affordability issue was at the core of what I intended the thread to deal with.

 

[GTX]

The 'no holds barred one'? I hope we can remain polite and discuss this over here, since the affordability issue was at the core of what I intended the thread to deal with.

We can have a discussion here, but it does not need to degenerate into yet another anti-F-35 crusade by some.

 

[LowObservable]

I think that discussion of the costs involved in STOVL is appropriate in this thread, and I'll be glad to respond to any questions about the stated facts in my post above.

And by "qualification" I did not mean any individual's qualifications, but unqualified (that is, complete and unconditional) acceptance that the economic thesis behind JSF has been proven correct.

 

[Grey Havoc]

Leaving aside the F-35 for a moment, is it perhaps time for designers to look again seriously at stoppable and stowed rotor designs for CAS & other battlefield aircraft?

 

[jsport]

Leaving aside the F-35 for a moment, is it perhaps time for designers to look again seriously at stoppable and stowed rotor designs for CAS & other battlefield aircraft?

second that emotion .in particular exploring the return of Canard rotor wing (CRW) research.

 

[SteveO]

Role of STOVL -

• Blow stuff up, kill people, move stuff from A to B, C4ISTAR. Same as CTOL or CV but STOVL can do it from more locations!
  

Suitability of STOVL -

• Suitable if you don't have many aircraft and airfields to operate from and you would like the option to disperse your forces in the event of conflict.
  
• Suitable if you would like to project airpower from the sea without massive investment in equipment and training.
  
• Suitable if STOVL method isn't overly complicated, expensive and hard to operate.
  
• Suitable if STOVL performance meets your requirements at an acceptable cost when compared to CTOL or CV alternatives.