The F-35 Thread

[Pilotasso]

there is no endgame for weapon VS countermeasure.

[Boagrius]

there is no endgame for weapon VS countermeasure.

 

True but that does not change the fact that post merge, "tail chase" dogfighting has diminished dramatically in terms of operational relevance over the last 50 odd years, and this is reflected in western air combat doctrine today. The emergence of directed energy weapons is probably only going to further this trend down the track.

 

The simple reality is that network-centrism is the overriding doctrine in the west, and is likely to remain that way for some time. The F35 is well designed to fit in with this philosophy.

[ФрогФут]

I've probably already thrown that bone, but can't remember the result.

If you may have to dogfight, there are enemy aircraft in the air. To dogfight you need WVR missiles (AIM-9). F-35 should sacrifice stealth to carry AIM-9 on externals. But if there are enemy aircraft you do want to keep stealth and advantage in SA and BVR.

Logic?

[Kuky]

Dogfights with guns will always be there. Maybe one day missiles and/or bullets will be replaced with lasers, but when all else fails... bullets will always work and can never be decoyed. I would never rule it out.

 

And I think the only reason why dogfights diminished is because lately all wars were fought with big guys bombing the little guys on the ground. Once the big guy tries to fight another big guy... it will be back in no time.

Edited March 8, 2016 by Kuky

[Emu]

Dogfights with guns will always be there. Maybe one day missiles and/or bullets will be replaced with lasers, but when all else fails... bullets will always work and can never be decoyed. I would never rule it out.

 

And I think the only reason why dogfights diminished is because lately all wars were fought with big guys bombing the little guys on the ground. Once the big guy tries to fight another big guy... it will be back in no time.

Oh sure bullets can't be decoyed, as long as you:

 

a) Are inside 300-400m; and

 

b) Manage to accurately snipe an aircraft doing 400-600mph by precisely pointing the nose of an aircraft whilst experiencing 9g of lateral loading, which is basically akin to trying to shit through your nose whilst treading an unpredictable needle that's doing 600mph.

 

Now part b) is tricky, because in getting here you've implicitly made the assumption that radar won't work, so finding a gun solution without radar is going to be a little WWII, finger in the air, spray and pray. And if you fire a hundred bullets, and the enemy doesn't change direction as you're firing, maybe you'll get lucky, or maybe you won't, or maybe your gun will jam. So we see bullets actually have many countermeasures, range, speed, direction, interfering with the gun solution etc. They can't be decoyed, but then neither can the ground, which has ironically proven far more lethal to aircraft than bullets in the last 25 years, both in war and in peace.

 

Like it has been said before, today we also have better countermeasures. It's not by accident the US navy has been lobying for a larger IR stick and all airfroces have retained the gun.

But those larger IIR missiles will still achieve BVR kills and failing that, they'll stuff enemy aircraft in the face whilst still closing WVR.

 

Only one gun kill in Ethiopian-Eritrean air war and that was finishing off an aircraft after a missile had already achieved a mission kill. That was with aircraft using the R-27R, which performed worse dog poop to put it mildly. All but 2 kills were made using R-60/R-73, which are IR missiles (not IIR) and lack the capabilities of AIM-9X/MICA IR/ASRAAM.

 

https://en.wikipedia.org/wiki/R-27_(air-to-air_missile)

https://adalvoice.wordpress.com/2008/04/18/quarrels-over-the-border/

 

In the 1999 Eritrean-Ethiopian War, Eritrean MiG-29s fought Ethiopian Su-27s both piloted by Russian mercenaries.[6] There were possibly as many as 24 R-27s fired by both sides. Only one R-27 fired by an Ethiopian Su-27 at an Eritrean MiG-29 proximity-fuzed near enough the MiG that the damaged aircraft eventually crashed on landing, giving the R-27 a hit ratio of only 4%.[7][8]

 

I've probably already thrown that bone, but can't remember the result.

If you may have to dogfight, there are enemy aircraft in the air. To dogfight you need WVR missiles (AIM-9). F-35 should sacrifice stealth to carry AIM-9 on externals. But if there are enemy aircraft you do want to keep stealth and advantage in SA and BVR.

Logic?

I know the ASRAAM is being integrated as an internal and external carry on the UK F-35.

 

The damn crazy thing is that if you plonk the F-35A at the same internal fuel fraction as a Gripen NG or F-16C, that gives it a weight of 41,000lb, a T/W of 1.05 and a wing loading equal to the F-16C, whilst still providing for internal carriage and carrying a targeting pod and having EODAS, HMCS and HOBS/LOAL IIR missiles. And apparently the nose pointing ability is well above F-16 level. Is it really as bad as many people think it will be in a dog-fight? The Gripen NG which many Sprey-ites praise as 6th gen, has a T/W of 0.88 with the same internal fuel fraction (29%) and has to lug around external stores, which will have a relatively high impact on a light aircraft.

 

[ame]http://saab.com/globalassets/commercial/air/gripen-fighter-system/gripen-ng/technical-brochure-gripen-ng-english-ver.2-jan-2015_low.pdf[/ame]

Edited March 8, 2016 by Emu

[GGTharos]

You're throwing away stealth though. The RCS is still going to be tiny, and so ECM and CMs become more effective.

 

Most likely but the time they are carrying AIM-9 they already mostly have air superiority and now it's more of a numbers game. Losing some stealth may not matter as much then.

 

I've probably already thrown that bone, but can't remember the result.

If you may have to dogfight, there are enemy aircraft in the air. To dogfight you need WVR missiles (AIM-9). F-35 should sacrifice stealth to carry AIM-9 on externals. But if there are enemy aircraft you do want to keep stealth and advantage in SA and BVR.

Logic?

[Rangi]

Have you tried turning it off and on again?

http://www.theguardian.com/technology/2016/mar/08/radar-glitch-requires-f-35-fighter-jet-pilots-to-turn-it-off-and-on-again

lol.

[ФрогФут]

You're throwing away stealth though. The RCS is still going to be tiny, and so ECM and CMs become more effective.

 

Most likely but the time they are carrying AIM-9 they already mostly have air superiority and now it's more of a numbers game. Losing some stealth may not matter as much then.

If you already have air superiority, then merging into dogfight, which a lottery, is a tactical failure.

Pylon is drag, pylon is RCS itself and you should also consider re-reflections from fuselage-pylon with missile. Unlikely it's going to be used for anything, than hunting down helicopters.

The ASRAAM for UK F-35 is a more interesting thing, but F-35B itself is overweighted and has increased drag, compared to A, which makes it worse in turns.

The whole thing about dogfight in f-35 news is more to calm down customers, than the real deal.

[GGTharos]

If you already have air superiority, then merging into dogfight, which a lottery, is a tactical failure.

 

I disagree. I can be a lottery and can be a failure, but it does not have to be either. A merge (or at least WVR encounter) can be forced by a number of factors.

 

Pylon is drag, pylon is RCS itself and you should also consider re-reflections from fuselage-pylon with missile. Unlikely it's going to be used for anything, than hunting down helicopters.

 

The pylon could also be built to preserve stealth :) In any case, so the guy can detect you at 20nm instead of 6nm. You've already run your BVR tactics, you have missiles in the air by the time he just gets to launch.

 

The whole thing about dogfight in f-35 news is more to calm down customers, than the real deal.

 

Sure - it's build as a strike fighter to begin with, not a dogfighter. It's more of a replacement for F-111/F-15E/F-18, and it can sort of act like an F-16.

[RoflSeal]

Block 4 upgrades for the F-35 (happening in 2020+) specify integration of AIM-9X Block II which indicates that AIM-9s will probably be carried internally (as Block II is Lock On after Launch)

 

[Emu]

ASRAAM new build. Sounds interesting. Based on CAMM maybe?

[SkateZilla]

ASRAAM / AIM-132 is already in service w/ RAF on the Eurofighter.

 

It's a bigger better IR Missile than the AIM-9, Google and read design specs and development.

[GGTharos]

It's the same mass as an AIM-9.

 

The diameter is larger which means it can probably burn more rocket fuel than the AIM-9 initially. It's possible that it has more propellant as well, but generally this wouldn't be the case as it depends heavily on a lot of factors.

 

So, it'll be about same-ish range as the AIM-9X - it's less draggy aerodynamically (more pointed nose), but it's wider, so it's a bit of 'anyone's guess' :)

[SkateZilla]

does AIM-9X have L.O.A.L?

[GGTharos]

Block II does. Figuring out how the two missiles compare is complicated from just looking at parameters though.

 

Thinkin about it more, believe the ASRAAM will have longer range in non-maneuvering scenarios:

 

It's aerodynamically much cleaner (lower Cd) than AIM-9X (but AIM-9X is much cleaner than 9M, too) because the main driver of drag is the nosecone. The more you approach the radome shape of RF missiles (ogive), the lower the Cd. It lacks a lot of finnage, so again, lower Cd.

It's rocket motor is dual-grain, so it'll likely keep the missile accelerating longer, and possible to higher velocity. The motor is claimed to be 'very high impulse' which is important.

So, higher speed at burn out and less drag means starting with more speed and keeping more speed = longer range.

 

Combine with lofting and other fun stuff, and you can attack targets that won't maneuver much from fairly far away.

 

Although there's some form of comparison the BVR missile ranges, that's pretty much silly IMHO. It's a very long-range capable WVR missile ... but there's a reason why BVR missiles are twice its weight.

Edited March 8, 2016 by GGTharos

[HiJack]

Missile technology does not stop to evolve. AIM-9X is already quite old. There is a DARPA supported project that will replace the 120 on a factor 6:1 in the internal bay if they succeed. Sure something similar is happening to the AIM-9 ;)

[GGTharos]

There have been a lot of projects that would replace the AIM-120 .. and got cancelled. INstead, we keep seeing improved 120s.

 

Same with 9X ... take the proposed Block III as an example.

 

Missile technology does not stop to evolve. AIM-9X is already quite old. There is a DARPA supported project that will replace the 120 on a factor 6:1 in the internal bay if they succeed. Sure something similar is happening to the AIM-9 ;)

[HiJack]

Well, it sure will make it difficult for any spy to know what is in the bay of the clean F-35 he sees take off unless he is located on the ramp/carrier during load.

[GGTharos]

That's true, packing more stuff into the internal bay is more better usually.

[Emu]

ASRAAM / AIM-132 is already in service w/ RAF on the Eurofighter.

 

It's a bigger better IR Missile than the AIM-9, Google and read design specs and development.

I know, but when it says 'New Build', what does it mean?

 

It's the same mass as an AIM-9.

 

The diameter is larger which means it can probably burn more rocket fuel than the AIM-9 initially. It's possible that it has more propellant as well, but generally this wouldn't be the case as it depends heavily on a lot of factors.

 

So, it'll be about same-ish range as the AIM-9X - it's less draggy aerodynamically (more pointed nose), but it's wider, so it's a bit of 'anyone's guess' :)

The range is quite a bit increased.

 

[ame]

[/ame]

 

In fact CAMM, which is based on ASRAAM, is only marginally longer (3.2m vs 2.9m) and manages >25km from a ground launch, which is 25% more than a MICA-VL (rated at 80km air-to-air - http://spsmai.com/exclusive/?id=19&q=MICA-missile-for-upgraded-Mirage-2000), so I would say the video is conservative.

 

http://www.mbda-systems.com/?action=force-download-attachment&attachment_id=5906

 

The ASRAAM's internal volume is 71% more than an AIM-9 (so a fair chance of a good bit more propellant), it's also dual burn. Think about it, would AMRAAM have about the same range if it were 138mm wide instead of 180mm?

 

Load wise, it still manages 50g, and doesn't rely on TVC, which will become dead-weight after the burn phase.

Edited March 8, 2016 by Emu

[GGTharos]

In fact CAMM, which is based on ASRAAM, is only marginally longer (3.2m vs 2.9m) and manages >25km from a ground launch, which is 25% more than a MICA-VL (rated at 80km air-to-air

 

That rating doesn't mean anything without parameters.

 

The ASRAAM's internal volume is 71% more than an AIM-9 (so a fair chance of a good bit more propellant)

 

No, it's not a fair chance of more propellant. It has the same mass as sidewinder, and having larger internal volume already implies a heavier airframe. Assuming you have savings in electronics, you might be able to implement a similar weight of propellant in ASRAAM.

You can get 'more fuel' in two ways, not mutually exclusive:

 

Lighter motor casing (possible but quite advanced), and higher fuel ISP. It's also possible that there is a significant reduction in electronics weight, but I don't see why that would be the case in comparison to sidewinder.

 

, it's also dual burn. Think about it, would AMRAAM have about the same range if it were 138mm wide instead of 180mm?

 

AMRAAM carries twice the fuel by mass that a sidewinder does. It also accelerates faster. ASRAAM has little wiggle room when it comes to mass though. Dual burn - ok, but duel burn is more efficient in all-boost in specific circumstances.

 

Load wise, it still manages 50g, and doesn't rely on TVC, which will become dead-weight after the burn phase.

 

Again, doesn't mean much. TVC is an enhancement for reducing Rmin. 50g load factor is great, but it's also one-turn-and-fall-out-of-sky.

[Hummingbird]

You also have to consider how much lift is generated by the body of the F35 (perhaps a more overt body lift design than the Hornet), and factor in the total lack of external stores and associated drag in an operational setting.

 

The F-18 enjoys said effect as well whilst also featuring a better blended wing body design than the F-35, so while the F-35 no doubt will generate lots of lift with its wide fuselage it probably won't be very efficient at it due to the boxy shape.

 

In the end I don't see the F-35 (A & B) being able to achieve the lift to weight ratio of the F-18, something which IMO is very well illustrated by the fact Lockheed had to increase the F-35A's wing area by over 40% to make the C model carrier capable.

 

The unfortunate reality is we just don't know what kind of pitch/turn rates the F35 is going to be capable of. That said, "Hornet/Falcon-esque" strikes me as a decent ballpark guess... and a ballpark guess is about all we can realistically expect for now.

 

I really don't believe the F-35 will ever be able to match the F-16 in sustained turn rate, infact I believe the disparity will be rather large.

 

Perhaps it'll be able to match an F-18 (the C might even best it), we'll see, but considering that the Hornet will do 10 deg/sec sustained at 15 kft with no less than three bags I really doubt it.

 

So does this mean that the F-35 will be a poor aircraft? No not at all, just one less suited for the traditional WVR dogfights and fast intercepts in comparison with some of the currently operational fighters. It will no doubt be an excellent strike aircraft though, likely the best we've seen due to all those high tech sensors it will come crammed with.

Edited March 9, 2016 by Hummingbird
added clarity on opinion between variants

[Sweep]

"Unobserved entry"

 

Makes up for a lot of that 'STR disadvantage'! :)

[Hummingbird]

"Unobserved entry"

 

Makes up for a lot of that 'STR disadvantage'! :)

 

No doubt, and I've never been of the opinion that the F-35 was going to be an easy opponent for any fighter either, its impressive sensor suite should make it competitive and deadly to anything out there - providing it works as advertised of course.

[Mike5560]

I really don't believe the F-35 will ever be able to match the F-16 in sustained turn rate, infact I believe the disparity will be rather large.

 

Perhaps, but at what speed though? The Viper becomes hampered below 300 KIAS, IIRC if it can be lured into a slow turning fight. Realistically, if the F-35 were to merge with a 4+ Gen fighter, it's likely to be a Chengdu, Mig or Sukhoi..........at least the latter of the two historically boast impressive low speed maneuverability.