McDonnell Douglas F-4 Phantom II Ideas and Inspiration

[Weaver]

I think it might take a bit to fit a TF30 into the F-4

Okay then, fit it with an afterburning TF-41. The point is to leverage the work done on the UK F-4s to get a quick'n'dirty Phantom with more power. If the F-14 had been cancelled in about 1970, then most of the other options wouldn't have been mature enough.

Thing is, while the TF41 is a variant of the Spey, it's a different model than that used for RAF/FAA usages and has a diameter similar to the TF30.  Now, an afterburning TF41, based on 1967 testing as reported in AW&ST would give you 27,000 lbt per engine in full burner; two of those could make for quite a hot bird.

I will note that the JTF16 engine was running in 1966 and could have been used as the basis for a new Phantom engine.

So if a TF-41 is a Spey with a bigger fan, then make a TF-41 variant with a Spey fan, i.e. a Spey. Already in production in the UK and large chunks of it already being put together by Allison in the US.

[elmayerle]

Not just a bigger fan, but a bigger core, too, as another stage of compressor was added (as also appeared in later civil Speys and it's Tay derivative).  I believe the bypass ratio stays the same, just the core gets larger.  Now I do understand that McDD did look at F-4 variants with TF30's (I believe the old Aerofax Minigraph on the F-4E mentions them in passing) and replacing those with TF41's would be nice.  For that matter, Allison was proposing the afterburning TF41 as an alternative to either the TF30 or F401 for export F-14's (considering that, on test, it matched the F401 in thrust, even if it didn't have as low a fuel consumption, that would be a reasonable swap).

[The Big Gimper]

AIM-54s on a Phantom.... How about using the conformal fuel tank suggested below with some recesses for semi-conformal carriage of a pair of Phoenixes under the belly. Less draggy and still carrying a decent amount of fuel.

I believe it was for fuel only...specifically 1,100 US gal (4,230 L).

I'm fairly sure I've seen a pic of a bomb pallete carried under a Phantom's belly in trials at China Lake, but I can't find it at the moment.
EDIT: It's on chinalakealumni.org (LINK!), about twenty pics or so down. Caption reads: NAF "China Lake F-4B Phantom II BuNo 148393, with nine Mk 117 750 lb. bombs, China Lake, circa 1974. Testing supersonic bomb delivery from Boeing's Conformal Carriage low drag interior bomb racks. Photo from Charlie Souza."

Funny I was looking through my F-4 book a few days ago and thought it would be cool to build the F-4 "Super" Phantom.

Did anyone make a 1/72 conversion kit? If no what would be the best medium(s) to build the fore and aft fairings and the central tank? Standard Sheet Polystyrene stock?

[Weaver]

You could always make Freightdog's day by modelling this loadout:



From here: https://twitter.com/CcibChris/status/744106651137998849

[Volkodav]

Now just imagine that loadout with fire and forget MM wave radar and / or laser guidance kits fitted to the rockets?

[Weaver]

Still a bit tricky in the 51mm Microcell calibre used by the RN, but yeah, ten pods full of 70mm APKWS would be errr, potent.  

[Volkodav]

With miniaturisation 51mm may not be far off, maybe we could see a return of retractable rocket packs on combat aircraft.

[apophenia]

I'm fairly sure I've seen a pic of a bomb pallete carried under a Phantom's belly in trials at China Lake, but I can't find it at the moment.
EDIT: It's on chinalakealumni.org (LINK!), about twenty pics or so down. Caption reads: NAF "China Lake F-4B Phantom II BuNo 148393, with nine Mk 117 750 lb. bombs, China Lake, circa 1974. Testing supersonic bomb delivery from Boeing's Conformal Carriage low drag interior bomb racks. Photo from Charlie Souza."

The sideview photo from the same collection gives a good idea of the depth of the Boeing Conformal Carriage.

[GTX_Admin]

With miniaturisation 51mm may not be far off, maybe we could see a return of retractable rocket packs on combat aircraft.

Interesting idea - mind you, when you start talking about miniaturised audience systems you are more into the realm of mini-missiles rather than the old un-guided shotgun style rockets.

[Volkodav]

Depends entirely who is in the audience, Russians for instance call guided missiles "rockets" don't they?

That would be the ultimate upgrade as far as I am concerned, retractable packs for guided rockets/missiles to replace WVR missiles and perhaps even guns and intermediate range missiles for air to air and air to ground applications, leaving only extended range missiles and larger air to ground ordinance for weapons bays and hard points.

[Weaver]

I doubt whether FFARs would be modifiable into viable AAMs without changing them out of all recognition and making them incompatible with compact standard FFAR launchers in the process. The 'guided rocket' weapons are intended to do the minimum neccessary, for the minimum price, to improve the lamentable accuracy of unguided rockets to the point where fewer need to be used to hit the target. Essentially, they're looking for gun levels of accuracy from a rocket. There's a world of difference however, between making something that can hit a stationary target on the ground from a diving plane and something that can hit a fast, maneuvering aircraft that's miles way.

To my mind, the best use for cheap guided rockets is as a 'recoilless GAU-8', giving a strike aircraft the ability to bolt on a reasonably accurate WVR air-to-ground system with lots of stored kills without having to deal with the design compromises of a huge internal gun or the problems of accuracy and alignment that come with a traditional gun pod.

[elmayerle]

You could always make Freightdog's day by modelling this loadout:



From here: https://twitter.com/CcibChris/status/744106651137998849

Query, the outboard hardpoints are each carrying just rocket pods or a pair of the combined rocket pod/fuel tank stores?  the later possibility could make for interesting stores for an AdlA or Aeronavale Phantom II.

[Kelmola]

Query, the outboard hardpoints are each carrying just rocket pods or a pair of the combined rocket pod/fuel tank stores?  the later possibility could make for interesting stores for an AdlA or Aeronavale Phantom II.

Was the British equivalent of TER "wet"? The outboard harpoints themselves were of course, but I've never heard of drop tanks being carried on a multiple-release rack on a 'Toom or any other plane for that matter... though of course, it could be possible to include the necessary valves and connections to the rack. Except that it adds weight and complexity, unless of course the intention is precisely to regularly carry multiples of rocket/fuel pods (several small "pure" fuel tanks instead of one big one don't really make sense, unless it's WW3 and you are so short on everything you're relying on scrap WW2 drop tanks).

Actually, if you are limited by hardpoints rather than the maximum weight, that kind of solution would actually make perfect sense. Why carry only fuel or rockets if you can carry both?

[elmayerle]

The reason I asked is that there are double racks for the rocket pod/fuel tank combo, though they are over-wing on the Lightning.  Still, looking at single rocket pod/fuel tank combos on the outboard pylons of French Phantoms with a twin-DEFA gun fit replacing the M61 in the nose and ATAR 9K's replacing the J79's.

[Daryl J.]

Mmmm....rumor has it Hasegawa is re releasing their UK Phantoms.   With those big intakes  some RF-4X variants may just have to happen!   :)

[Weaver]

The reason I asked is that there are double racks for the rocket pod/fuel tank combo, though they are over-wing on the Lightning.  Still, looking at single rocket pod/fuel tank combos on the outboard pylons of French Phantoms with a twin-DEFA gun fit replacing the M61 in the nose and ATAR 9K's replacing the J79's.

The Lightning overwing load used a custom adaptor, not a TER though. The setup on the phantom was 'show only' so I suspect they were just regular rocket pods.

Note that the JL-100 combined fuel/rocket pod used 68mm SNEB rockets with two rings of tubes, while the pods in the F-4K pic are Microcell 2" (51mm) pods with three rings of tubes. I've never seen a JL-100 variant with 51mm tubes, nor would I expect to since they're a French store and the 2" RPs are British. Having said that, I see no reason in principle why a JL-100-style pod couldn't be made up with 2" tubes. I think the diameters of the two pods are pretty similar.

BTW, the reason that the RN used the 2" RPs while the RAF went to 68mm SNEBs was that the latter wern't sufficiently hardened against RFI problems for the shipboard environment. When RAF Harriers went to the Falklands, they had to be quickly cleared to fire Navy 2" RPs for that reason.

Another solution to the gun 'problem' with British/French Phantoms would be to adopt the Vulcan II cannon developed just after the 20mm Vulcan but never put into production. This used the ADEN/DEFA 30x113mm ammo and was roughly the same size as the 20mm weapon. Since the US had no interest in it, you could probably licence-produce it in the UK and/or France.

If the French Phantoms were to be used from their carriers, then ATAR-9Ks would be a very poor choice since their thrust and thrust/weight ratio were significantly worse than the J-79. If anything, they'd probably have to adopt the UK Spey fit for the same reasons: safe take-off from weaker catapults than the US ones and faster response to a throttle slam in the event of a go-around.

[elmayerle]

Hmm, I've got several JL-100's coming, have to see what I can put together using 2" RP launchers for British use.

I'm thinking the French would want as much French content as possible and so would go with the ATAR's and DEFA installations.  Not sure if they'd be carrier birds or land-operated (thinking more likely AdlA operation to replace their F-100's).

On the other hand, that Vulcan II sound like it could be good for Anglo-French production for French F-4E's and British gun-nose F-4M2 (F-4P?) Spey-powered Phantoms.

[Weaver]

The French really didn't have an engine that was competitive with the J-79 though. Even their large Mirage variants of the 1960s that didn't go into service depended on US turbofans.

[elmayerle]

Oh, I know and agree, it's just that I can't see the French of the 60's wanting to use an American engine if they could possibly avoid it, even at the expense of a hit in performance.

[Volkodav]

The French were not, however, adverse to using or optioning British engines when it served them, maybe an evolved Avon could have been an option.  Then again they did use the TF30 on the Mirage F2 and G so would the use of the J79 be such an issue?

[elmayerle]

I don't know, though I reckon that an evolved Avon would be better received than a J79.  I suspect the derivatives of the same technology and core as the TF30 were used because P&W had a 10% share of SNECMA at the time.  In any case, my model will use ATAR 9K's with the J79's going into a pair of Mirage F's.

[GTX_Admin]

Remember that in March of 1963, McDonnell had tried to interest the Royal Australian Air Force (RAAF) in a version of the F-4C (Model 98DX) powered by a pair of French-built SNECMA Atar 9 turbojets so there is a basis for a French one.  Moreover, given the higher thrust (dry and augmented) of the 9K vs the original 9C the performance shouldn't be too bad.  One might also address any performance issues with some weight reduction activities.

[Weaver]

Remember that in March of 1963, McDonnell had tried to interest the Royal Australian Air Force (RAAF) in a version of the F-4C (Model 98DX) powered by a pair of French-built SNECMA Atar 9 turbojets so there is a basis for a French one.  Moreover, given the higher thrust (dry and augmented) of the 9K vs the original 9C the performance shouldn't be too bad.  One might also address any performance issues with some weight reduction activities.

That's interesting: a French Phantom might be similar to the 'lightweight' Luftwaffe F-4Fs.

[Volkodav]

I tried to reply to this earlier but hit tech issues that seem to have gone now.

I recall that the Atar Phantom was as offered as a potential Canberra replacement.  Now here’s a double barrel what if, Australia selects the Avon for their Mirage IIIEO fleet and as result McDonnell offers the same engine in the Phantom.

Triple Barrel:
Having determined that there was no realistic way Phantoms were going to be operated from Hermes or Victorious, let alone Centaur, combined with some concerning wind tunnel results on the drag associated with the Spey conversion of the Phantom, the RN, in conjunction with RR suggest an enhanced Avon variant instead.

End result the Avon Phantom ends up serving with Australia (F-4D/E/G RF-C), the UK (F-4M&K) and is also eventually adopted by France (a version of the K)

[GTX_Admin]

Looking quickly at the stats, a RR Avon engined Phantom might work.