MOTS Phantom for the RN?

[Rule of cool]

I'm putting this here because the premise is alternate reality.

Its a world where the RN focuses on its big carriers, Eagle rebuilt as per normal, Ark Royal getting its 'Phantom' refit starting in 1964 and CVA01 & 02 getting started as soon as the Fearless class are off their slips at JB and H&W. Additionally the RAF went with the Lightning for its 1958 fighter-bomber requirement, so there is no P1154 leaving the RN with a requirement for a Sea Vixen replacement with no convenient British type to do it but no burning desire to Anglicise something foreign.

What is the closest the RN can get to a Military Off The Shelf Phantom buy, starting in about 1963? Without having to worry about the Hermes and Vic does the Spey need to be fitted? IIUC the extended nose oleo and drooping airlerons were McD ideas not adopted for the USN. What about the 'bring back' requirement for ordnance, is the F4Js capability enough for this?

 

[CV12Hornet]

Let's do some math.

We know thanks to the Standard Aircraft Characteristics that the F-4J had a stall speed around 140 knots at around 50,000 pounds with air to air loads. Taking the rule of thumb of minimum takeoff speed being 1.2 times stall speed, that works out to the catapults needing to get the plane to 168 knots.

Given the BS-5A fitted to the waist on Ark Royal was rated for only 105 knots at 50,000 lbs, we can pretty easily conclude that flying stock F-4Js off of Ark Royal would be impossible.

By comparison, the F-4J had a minimum launch speed of 130 knots at 50,000 lbs. Quite the difference! This allowed Ark to launch F-4Ks from the waist position in all wind conditions.

IIRC the extended nosewheel and drooping ailerons reduced stall speed by 12 knots or so, but I might be misremembering. So we have a stall speed of 128 knots, which works out for a minimum launch speed of 153.6 knots. This would require a minimum of 18-knot winds just to launch from the waist cat, let alone the bow cat! This is fairly plainly impractical. So for flying off Ark, yeah, you need the whole suite of takeoff aids, including the Spey engines.

If it was just CVA-01 they could use stock F-4Js with no modification.

 

[Rule of cool]

I've read the same about the oleo and airlerons, 12-15 knot reduction in launch speed.

The Spey not only had more thrust and bleed air but also the thrust line was angled down by 2 degrees compared to the J79.

I've read that 15kts over stall speed is enough, but in war they'll launch at 8kts if need be.

 

[uk 75]

Spey Phantoms were the only option for HMS Eagle, which was the original carrier planned to operate through the 1970s. CVA01 was designed to operate bigger and heavier aircraft like the F111B.
Even the Spey Phantoms were too much for Hermes which was expected to use Buccaneers in the strike role working with either Eagle or CVAO1.
In the longer term the RN expected to operate CVA01 and 02 into the 80s with a single VG type (AFVG was planned).
It was the RAF which might have looked at other Phantom variants, since it had no carrier requirement.

 

[Rule of cool]

So would it be cheaper to let McD do as much as possible, without trying to squeeze the 40% (or whatever) British content?

 

[Pirate Pete]

I seem to recall that the operation of 'Standard' Phantoms from Ark Royal etc has been discussed previously. Whatever their loadings, Ark Royal definitely cross-decked with I think USS Saratoga...

 

[Rule of cool]

I've seen A7s on the Ark as well, but that's a long way from being able to launch combat loaded sorties in poor conditions like low wind and hot temperatures with a dirty hull.

 

[BlackBat242]

Remember, the need for the engine and control surfaces changes for HMS Eagle/Ark Royal was determined in the early years of F-4B operation... the F-4J came along just before the F-4K (FG.mk 1) flew.

Data from NATOPS manuals, as well as some info from the book 'Phantom from the Cockpit - Flying the Legend'.

Minimum safe Take-off speed at weight
F-4B - ~162 knots at 52,000 lb
F-4J - 156 knots at 52,000lb
F-4K (FG.mk 1) - 152 knots at 52,000 lb

Approach speed (with 2 empty drop tanks):
F-4B - 145 knots;
F-4J - 138 knots;
F-4K (FG.mk 1) - 138 knots

no drop tanks:

 

[zen]

So would it be cheaper to let McD do as much as possible, without trying to squeeze the 40% (or whatever) British content?

Not simple, because F4 had to release UK nuclear tactical weapons and intigrate with UK carrier combat system ADA later ADAWS, and us UK radios, and use other UK equipment.

So it was always going to be modified from standard USN F4s of any flavour.

 

[A Tentative Fleet Plan]

I don't think F-4K was integrated with ADAWS, the UK didn't use Link 4, which was the NATO standard data link for aircraft.

 

[alertken]

One of F-4s' attractions for RAF was NATO standard AW. The decision, 6/4/63, for 5xSSBN to be at sea from 1968 with UK AW meant that post-Canberra RAFG would not have UK AW before mid-70s-ish, after 5xloadouts+pipeline (1/65 change to 4, not 5, advanced RAFG for 12/72 Buccaneers, ordered 4/66. It was Polaris AW enhancement, Chevaline (at sea 10/82, 2 not 3 warheads), and proper analysis of pipeline that liberated resources to create enough WE177C for Jaguar to replace F-4M/B-57 after 12/75).

The only cases I know of hanging USAW on non-US airframes are NDB in Italian/Neths. Atlantic, RAF Shackleton MR2/3, Nimrod, and B61 on Italian/FRG Tornado. No UKAW on US airframes, except WE177NDB on Sea King/Wessex 3.

RN confined UK AW to Buccs, no AW role for F-4K.

 

[CV12Hornet]

I seem to recall that the operation of 'Standard' Phantoms from Ark Royal etc has been discussed previously. Whatever their loadings, Ark Royal definitely cross-decked with I think USS Saratoga...

As noted, those are Phantoms with no weapons and likely as little fuel as they can get away with.

I've read the same about the oleo and airlerons, 12-15 knot reduction in launch speed.

The Spey not only had more thrust and bleed air but also the thrust line was angled down by 2 degrees compared to the J79.

I've read that 15kts over stall speed is enough, but in war they'll launch at 8kts if need be.

Minimum safe Take-off speed at weight
F-4B - ~162 knots at 52,000 lb
F-4J - 156 knots at 52,000lb
F-4K (FG.mk 1) - 152 knots at 52,000 lb

Based on this data, yeah, 15 knots over stall seems about right.

156 knots for a stock F-4J would still be impractical off of a BS-5A; 144 is closer to reality but would still require a significant headwind, and would probably be impractical in service.

 

[EwenS]

Not simple, because F4 had to release UK nuclear tactical weapons and intigrate with UK carrier combat system ADA later ADAWS, and us UK radios, and use other UK equipment.

So it was always going to be modified from standard USN F4s of any flavour.

From everything I’ve read in discussions on the net over many years, including by those working on them at the time, British Phantoms were never cleared for the carriage of U.K. designed nuclear weapons (Red Beard & WE.177)

The RAF Phantom FGR.2 in RAF Germany were cleared for the use of US designed nuclear weapons assigned to NATO. And the stood QRA carrying these. They were succeeded in RAFG by Jaguar with WE.177.

 

[Kalarz]

I don't think F-4K was integrated with ADAWS, the UK didn't use Link 4, which was the NATO standard data link for aircraft.

F-4 did not use Link 4 until F-4J (from Friedman's Fighters over the Fleet), and considering F-4K was meant to operate from Eagle as well, which did have ADAWS, which from the same book used Link 11, it ought to be integrated already, unless 1960s Britain did something weird again which is totally possible.

 

[A Tentative Fleet Plan]

F-4 did not use Link 4 until F-4J (from Friedman's Fighters over the Fleet), and considering F-4K was meant to operate from Eagle as well, which did have ADAWS, which from the same book used Link 11, it ought to be integrated already, unless 1960s Britain did something weird again which is totally possible.

According to a table of NATO data-links in the appendix of Peter Marlands's article on Royal Navy AIO systems in Warship 2016, the Royal Navy and RAF abandoned Link 4 and didn't put it into service.

 

[Rule of cool]

Thanks for the replies folks. Basically there is no neat trick for the RN to get the Phantom cheaply and easily if a bunch of other stuff around it changed. The 151' BS5 bow cats on Ark and Eagle demand the F4K rather than pipe dreams about putting them in Hermes.

 

[pathology_doc]

They did buy a bunch of J's to replace wastage in K's and M's, and called them F-4J(UK), but I think all of those were RAF aircraft.

 

[Rule of cool]

Yes, post Falklands as a result of the need to station a Phantom sqn down there and keep up NATO commitments.

 

[orlovsky]

For the question "What is the closest the RN can get to a Military Off The Shelf Phantom buy", depends on how much mod you accept.
Completely unmodified something like internal fuel and missiles.

With the extended nose gear, about 50k lbs.

I have not seen evidence for the Spey actually improving carrier suitability - only in McAir's and RR's sales pitch.

Nose gear, definately.
Playing around with blc might happen.

The cat characteristics from the USN SAC: The c-11 was about 12-13 kts stronger, the extended nose gear reduces wod by 11-12 kts. So this can be taken as the starting point, and 50k lbs is the deck strength limit anyway. Works on Ark and Eagle.

View attachment 720068

The 175 ft bs5 planned for Hermes would need another 7 kts, and the ship speed is only 25 kts. So @ 50k lbs we'd need 21+20 (cat)-12 (nose gear) = 29, a few more in the tropics. 45k lbs might just work, ie internal fuel only, about 1h cap station. Here, people would start making plans...

The original plans show pretty much the same, via https://www.secretprojects.co.uk/th...order-of-battle-1975.20517/page-2#post-420283

View attachment 720069

 

[pathology_doc]

a Military Off The Shelf Phantom buy

As opposed to Civilian Off the Shelf buy?

"Hello, old chap, just looking to buy a supersonic fighter for me and the Mrs. to go on holiday. Got anything American?"

 

[Rule of cool]

As opposed to Civilian Off the Shelf buy?

"Hello, old chap, just looking to buy a supersonic fighter for me and the Mrs. to go on holiday. Got anything American?"

COTS is for ground support equipment like tow motors, ground power units and other stuff airlines use. The RAAF bought a COTS off road forklift then ruined it by Australianising it.

 

[pathology_doc]

COTS is for ground support equipment like tow motors, ground power units and other stuff airlines use. The RAAF bought a COTS off road forklift then ruined it by Australianising it.

I see - but I think the joke still stands.

 

[Rule of cool]

For the question "What is the closest the RN can get to a Military Off The Shelf Phantom buy", depends on how much mod you accept.
Completely unmodified something like internal fuel and missiles.

With the extended nose gear, about 50k lbs.

I have not seen evidence for the Spey actually improving carrier suitability - only in McAir's and RR's sales pitch.

I've read that the Spey provided more bleed air for for more powerful blown flaps, it's thrust line was 2 degrees downard from the J79 and of course it was ~15% more powerful especially at low levels. Assuming all of this is true then it would add up to better behaviour around the ship.

 

[orlovsky]

F-4K sales pitch (1st graph): in AB @ 50k lbs 118-129 kts (depending on sink)

F-4K actual manual (2nd graph): minimum launch speed in full AB @50k lbs is 137 kts (from another source, with 6ft sink)
F-4K minimum launch speed in mil @50k lbs is 165 kts (probably due to AB ignition problems)!

Unfortunately there is no apples-apples comparison for the F-4J. From the SAC, minimum launch speed in AB would be ~140 kts.
Add maybe 10 kts for 6ft instead of 15 ft of sink (if the SAC is based on that, who knows)
Subtract 12 kts for the extended nose gear.
Engines should be pretty much a wash in AB; in mil, the Spey added 28 kts vs the J79 3 kts over AB.

 

[Rule of cool]

So it looks like even if Britain did everything else as well as they could in the circumstances the RN will still be up for a hefty development bill and per unit price for Phantoms because of the BS5 and BS5A catapults. Oh well you can't win em all, even in alternative realities.

 

[pathology_doc]

So it looks like even if Britain did everything else as well as they could in the circumstances the RN will still be up for a hefty development bill and per unit price for Phantoms because of the BS5 and BS5A catapults. Oh well you can't win em all, even in alternative realities.

You can buy US Phantoms off the shelf for the RAF, but if you're going to buy them for the FAA too, then commonality makes sense and you're probably committed to the Spey version.

The alternative is for the RN to turn its back on full-size carriers earlier than it does IRL, which obviates the need to buy RN Phantoms at all. Given how utterly clapped-out the Ark Royal and Eagle were by this time and how expensive they were to refit for so few years in service, this might not be a bad thing. It probably leads to the Sea Harrier becoming a thing much earlier than it ordinarily would, and that could be paid for (in part, at least) out of the money that wasn't wasted on the Spey Phantom conversion.

 

[Rule of cool]

In my view the RAF getting the Phantom was a case of the tail wagging the dog, they got it because the RN got it. In my fevered brain the RAF shouldn't have needed the Phantom, however for all its fevers I can't seem to avoid the RN needing it and shouldering a massive bill as a result.

 

[pathology_doc]

In my view the RAF getting the Phantom was a case of the tail wagging the dog, they got it because the RN got it. In my fevered brain the RAF shouldn't have needed the Phantom, however for all its fevers I can't seem to avoid the RN needing it and shouldering a massive bill as a result.

It was either that or pay for P.1154 and hope that its development, particularly in engine terms, did not turn out to be as cursed as TSR.2's.

 

[uk 75]

The RAF could have replaced Lightnings in the 1970s with AFVG which could hàve also replaced Sea Vixen on Eagle and Hermes
Instead of CVA01 a new class of gas turbine powered Hermes sized carriers operating AFVGs and no Buccaneers could have been in service by 1980 with Eagle retiring in 1980 followed by Hermes in 1984 when the third CV80 enters service.
AFVG would have served on Foch and Clemenceau too.
TSR2 goes ahead in this scenario because the RAF is expected by NATO to deploy a Valiant replacement. It is less exotic than the real TSR2 with no rough field capability and step by step systems introduction.
P1154 is cancelled when NATO fails to adopt it.
A version of the P1127 Kestrel is developed instead.

 

[Rule of cool]

It was either that or pay for P.1154 and hope that its development, particularly in engine terms, did not turn out to be as cursed as TSR.2's.

That doesn't work if the RAF doesn't need the P1154 because of earlier decisions.

The big problem here is the RN will only ever want a small fleet of aircraft, but by the late 50s any new state of the art combat aircraft will cost a fortune to develop. Therefore the potentially huge development costs can only be amortised over a small production run. The Spey Phantom development was hoped to cost 25m but eventually cost 75m, which I'd still think is cheaper than other options.

 

[CV12Hornet]

Yeah, that's an issue I've been meaning to bring up in other RN carrier threads, and RAF threads, too: the Brits don't have a big enough force structure to justify more than one or two home-developed types, so they need to be picky about what they develop at home and what they buy from someone else (i.e. the Americans).

 

[Rule of cool]

If the development cost is low enough then a reasonably small production run isn't too much of a problem. However in the thermonuclear age the forces should strive to have as few types in as large a number as possible.

 

[BlackBat242]

Given how utterly clapped-out the Ark Royal and Eagle were by this time and how expensive they were to refit for so few years in service, this might not be a bad thing.

RN FAA Phantom given approval 1 July 1964. First 2 YF-4K prototypes flew in June & August 1966. First of 2 pre-production F-4Ks flew November 1966. First 3 F-4Ks (FG Mk.1) delivered to RN April 1968 or trials (including trials aboard HMS Eagle).

HMS Eagle: commissioned 5 October 1951; thoroughly modernized 5/59-5/64.
So only 9 years active service and newly modernized at the time the RN ordered its Phantoms.

HMA Ark Royal: commissioned 2 February 1955; given major refit (limited to flight deck & equipment required to operate Phantoms, her propulsion and auxiliary machinery were not modernized) October 1966-February 1970.
So only 9 years active service at the time the RN ordered its Phantoms.
That her machinery and non-aircraft equipment was not modernized as well was a choice that the RN initially made with the planned CVA-01 carriers in mind (Ark was supposed to be replaced by the second CVA-01, leaving the two new carriers and Eagle to operate Phantoms long-term). That there was no change to her Phantomization refit to extend her service past the late 1970s, and that Eagle was not scheduled for Phantomization (a much less-extensive and costly process due to her earlier modernization), were budgetary decisions in line with the two decisions made in late 1967 to both "withdraw from East of Suez" and to "get out of the aircraft carrier game".

So you see, both were actually in pretty good shape (and new carriers had been ordered) when the decision to order Phantoms was made.

The CVA-01 (and the planned -2, -3*, -4*) was canceled in February 1966... with almost all of the engineering work done for the RN's Phantoms... and with any UK-designed alternative to the Phantom for carriers and for the RAF (P1154) also canceled (or on unstable ground - see AFVG), by then it made little sense to cancel a program where there was already much development money spent and which was nearing production.

 

[pathology_doc]

The RAF could have replaced Lightnings in the 1970s with AFVG

Tell me again why AFVG ended.

TSR2 goes ahead in this scenario

Wasn't AFVG one of the things that followed upon the death of TSR2? I'm having trouble seeing how the various time-streams link up here. If TSR.2 goes ahead then AFVG has no impetus to actually happen, so how do the two coexist? Or does the Government somehow dig deep enough in its pockets to fund construction of an austere TSR.2 for the long-range nuclear strike mission (because at least the thing has shown that it flies like a God) and AFVG as well for battlefield tactical work?

"A version of P.1127" is of course what we actually got IRL.

 

[orlovsky]

So it looks like even if Britain did everything else as well as they could in the circumstances the RN will still be up for a hefty development bill and per unit price for Phantoms because of the BS5 and BS5A catapults. Oh well you can't win em all, even in alternative realities.

The cheap and simple option would have been the F-4J with the extended nose wheel. Gives you essentially the performance of the USN F-4J from the C-11 as on the Coral Sea.

 

[orlovsky]

Tell me again why AFVG ended.

Wasn't AFVG one of the things that followed upon the death of TSR2? I'm having trouble seeing how the various time-streams link up here. If TSR.2 goes ahead then AFVG has no impetus to actually happen, so how do the two coexist? Or does the Government somehow dig deep enough in its pockets to fund construction of an austere TSR.2 for the long-range nuclear strike mission (because at least the thing has shown that it flies like a God) and AFVG as well for battlefield tactical work?

For a while, the plan was for AFVG and in addition, F-111K as a TSR2 replacement. The cost of such a small production run of TSR2s would have been ugly, but maybe about the same as was burnt on TSR2 and F-111K development without a single copy entering service...

 

[pathology_doc]

For a while, the plan was for AFVG and in addition, F-111K as a TSR2 replacement. The cost of such a small production run of TSR2s would have been ugly, but maybe about the same as was burnt on TSR2 and F-111K development without a single copy entering service...

This is often what gets me. By the time you've scrapped TSR2, spent on F-111K without a single aircraft being delivered (they made, what, TWO that were never completed and then scrapped?) and ploughed money into AFVG only for that to fold too, one can be forgiven for thinking that continuing with TSR.2 was in fact the right answer.

If you're going to go down the F-111 route, fine; buy however many F-111A's off the shelf and be done with it. I suspect the TSR.2 fanatics wouldn't be quite so bitter, as they would no longer be able to say (justifiably) "You said you couldn't afford our airplane, but then you failed to bring BOTH of its successors to fruition at a cost of millions for essentially nothing".

The same goes for the thin-wing Javelin and the Arrow. Sure, any of the F.155T entrants would have run rings around a CF-105, but the Arrow was the interceptor with legs (which the Lightning didn't have) that the British arguably needed, and a combined Anglo-Canadian buy with AI-18 and Red Top until something better came along could probably have made it affordable. But the best being the enemy of good enough got in the way.

 

[BlackBat242]

If you're going to go down the F-111 route, fine; buy however many F-111A's off the shelf and be done with it.

Switching out the TF30s for reheated Speys would not be much of a problem, as (unlike the J79) the TF30 is slightly larger than the reheated Spey, and requires the same amount of airflow - so virtually no airframe mods (other than the internal engine mounting points and wiring/oil lines/etc connections) would be necessary. Changing out the radios etc for RN-compatible ones would likewise not cost much.

 

[Rule of cool]

The cheap and simple option would have been the F-4J with the extended nose wheel. Gives you essentially the performance of the USN F-4J from the C-11 as on the Coral Sea.

So the F4J can operate at combat weights from the 151' BS5 bow cats of Eagle and Ark when the RN is in 'coffin corner'; bombers inbound in low wind, warm temperatures, dirty hull slowing the ship down and the 199' BS5A waist cat broken?

 

[orlovsky]

So the F4J can operate at combat weights from the 151' BS5 bow cats of Eagle and Ark when the RN is in 'coffin corner'; bombers inbound in low wind, warm temperatures, dirty hull slowing the ship down and the 199' BS5A waist cat broken?

The comparison was for the 199 ft cat only, yes.

Going from the SAC, the long-noselegged F-4J would be limited to about 45k lbs (internal fuel+missiles) in nil wind ISA from the short cat.

But if you look at the graphs I posted above, the actual F-4K vs the catapult performance, the F-4K would also be limited to about 45k lbs.
Less in higher temperatures. At 35 °C you need 10 kts extra, ie ~4000 lbs less weight.
You may get a bit extra by accepting a higher rate of sink, but still not the weight with the full center line drop tank. That requires the long cat.