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What if, Grumman went with a fixed wing for the Tomcat

helmutkohl

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One of the designs for the Tomcat replaced the swing wings with a fixed wing. Such as the 303F

What if, in this alternate history.. Grumman decided to go with a fixed wing instead of a swing wing.
Then the question becomes

  • How would its performance characteristics be like with a fixed wing?
  • Would it be less maintenance intensive?
  • Cheaper to operate?
  • Would more or less countries have interest in it?
  • Would it last longer in service?
  • Would it have better payload capabilities?


1395473d1437846091-defender-fleet-grumman-f-14-tomcat-303f1.jpg
AV8PQ68PH0u4-wqNL9tjEu--E6OUIDsrm76i9NQsvNiwrh_D3Wwi0tIjK_g1GWnQvp5RNRhbq4MnQWcqFzvKIDQJ_1d2PTg
 

Manuducati

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According to the Aviation Fact File dedicated to the F-14, the 303F design was primarily created to emphasize the variable geometry superiority. According to Grumman, to retain the same level of performance as the baseline preferred 303E, a fixed wing design would be 2,520lb (1,143kg) heavier (dry) or 4,920lb (2,232kg) at take off gross weight. And heavier generally means more expensive. The weight increase comes from the larger wing, trim and lift devices. Bring back capability was lower and didn't met Navy requirements.

Of course those figures could be inflated to better suit Grumman goals.
 

CV12Hornet

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A fixed-wing Tomcat would likely be less maintenance-intensive and cheaper to operate, yes, simply due to having fewer moving mechanisms.

Whether it lasts any longer than it has is a political question, from all the posts I've seen about the mess that was naval aviation development in the 1990s. So this likely doesn't move the needle on that front.

I doubt this changes who buys the aircraft. The Tomcat is an expensive bird with capability few countries need either way; and that short list of potential customers mostly bought F-15s, valuing the F-15's climb rate and speed (and significantly lower procurement cost) over the Tomcat's loiter time and long-range interception capabilities. The new wing doesn't change this situation, as it was mostly an engine problem.

It would most emphatically not have better payload capabilities. If you believe Grumman about the increased weight of the fixed-wing version - and I'm inclined to, the larger wing, trim, and lift devices make sense for replicating the takeoff/landing benefits of the variable geometry wing - then that means more thrust devoted to just getting the aircraft off the ground and less for getting payload off the ground.
 

isayyo2

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It would look like a F-15B except with TF30 engines that suck. Maybe it would motivate the USN to provide better engines ?
Maybe go with a GE1 solution like the F101?

Without out the swing-wing it may be cheaper since the titanium requirements would be lessened.
The revolutionary air-data computer to handle the wing sweep would not be required
The fixed wings could haul two or three hard points making the Marines happy for the air-to-ground role.
 

Fluff

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A fixed-wing Tomcat would likely be less maintenance-intensive and cheaper to operate, yes, simply due to having fewer moving mechanisms.

Whether it lasts any longer than it has is a political question, from all the posts I've seen about the mess that was naval aviation development in the 1990s. So this likely doesn't move the needle on that front.

I doubt this changes who buys the aircraft. The Tomcat is an expensive bird with capability few countries need either way; and that short list of potential customers mostly bought F-15s, valuing the F-15's climb rate and speed (and significantly lower procurement cost) over the Tomcat's loiter time and long-range interception capabilities. The new wing doesn't change this situation, as it was mostly an engine problem.

It would most emphatically not have better payload capabilities. If you believe Grumman about the increased weight of the fixed-wing version - and I'm inclined to, the larger wing, trim, and lift devices make sense for replicating the takeoff/landing benefits of the variable geometry wing - then that means more thrust devoted to just getting the aircraft off the ground and less for getting payload off the ground.
I dont recall the Tornado having many problems with the swing wings, and there was no daily maintenance requirement, other than to visually check the crack propogation in the thin metal 'seals' . Would be a bit higher burden on deep servicing, but mostly a strip and inspect, which would be more or less the same for a fixed wing.
 

CV12Hornet

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It would look like a F-15B except with TF30 engines that suck. Maybe it would motivate the USN to provide better engines ?
They were quite motivated IOTL. But the failure of the F401 engine, and then the Ford and Carter-era defense cutbacks, meant re-engining was off the table until the F-14A+ program was started up in 1981. The former meant there wasn't a suitable engine available, given the ongoing headaches the Air Force was having with the F100; the latter meant there was no money to find a new engine anyway.
 

SSgtC

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It would look like a F-15B except with TF30 engines that suck. Maybe it would motivate the USN to provide better engines ?
They were quite motivated IOTL. But the failure of the F401 engine, and then the Ford and Carter-era defense cutbacks, meant re-engining was off the table until the F-14A+ program was started up in 1981. The former meant there wasn't a suitable engine available, given the ongoing headaches the Air Force was having with the F100; the latter meant there was no money to find a new engine anyway.
This is a sad but true fact of USN procurement. The USN has been repeatedly saddled with bad engines. Though the TF30 stands out as the absolute worst of the lot.
 

elmayerle

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I wouldn't say "failure of the F401 engine", more like deliberate termination/cancellation of the F401 engine. Representative Les Aspin wanted to emulate Sen. Proxmire, and led the charge to kill the F401 with the cry that "The TF30 is good enough!"; this was in 1974. Five years later, with the USN losing a bunch of Tomcats due to engine problems, he criticized that "The Navy bought a Turkey, not a Tomcat!" but never admitted his role in the problem. I will grant you that the F100 had it's share of development problems that likely would have been shared with the F401, but the F401's more "pushed" performance meant finding some problems before the F100 did (I know of at least two cases of this).

If I sound a bit bitter about Rep. Aspin, it's because the cancellation of the F401 led to my getting laid off from Pratt & Whitney and an eight-month period of unemployment.
 

SSgtC

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I wouldn't say "failure of the F401 engine", more like deliberate termination/cancellation of the F401 engine. Representative Les Aspin wanted to emulate Sen. Proxmire, and led the charge to kill the F401 with the cry that "The TF30 is good enough!"; this was in 1974. Five years later, with the USN losing a bunch of Tomcats due to engine problems, he criticized that "The Navy bought a Turkey, not a Tomcat!" but never admitted his role in the problem. I will grant you that the F100 had it's share of development problems that likely would have been shared with the F401, but the F401's more "pushed" performance meant finding some problems before the F100 did (I know of at least two cases of this).

If I sound a bit bitter about Rep. Aspin, it's because the cancellation of the F401 led to my getting laid off from Pratt & Whitney and an eight-month period of unemployment.
While you're right, the F401 wasn't all sunshine and roses either. Having both test engines fail their 60 hour tests in the same week was a huge black eye for the program. Then there's the fact that the Air Force honestly wanted to do their level best to fuck Naval Aviation in general and the Tomcat in particular. So they accepted reliability levels that they knew the Navy wouldn't just so they could stop funding the development needed to fix it. Why would they do that? Because to put it bluntly, Air Force pilots could divert to thousands of air fields when their engines shit the bed, while for the Navy, it was Carrier or Bust
 
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Mirage4000

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According to the Aviation Fact File dedicated to the F-14, the 303F design was primarily created to emphasize the variable geometry superiority. According to Grumman, to retain the same level of performance as the baseline preferred 303E, a fixed wing design would be 2,520lb (1,143kg) heavier (dry) or 4,920lb (2,232kg) at take off gross weight. And heavier generally means more expensive. The weight increase comes from the larger wing, trim and lift devices. Bring back capability was lower and didn't met Navy requirements.

Of course those figures could be inflated to better suit Grumman goals.
they are kind of true but not totally true.

Variable Goemetry offered very low speed flight.

F-15 has a lighter wing which proves Grumman was lying, the wing loading of F-15 is lower than the F-14.
1622155559638.png
However we have to consider wing swept, at low speed the ride of F-14 is better.


Su-27 added canards when navalized and MiG-29K a new wing when it was deployed operational.
1622155802195.png
Su-27 was chosen to lower speed approach over the MiG-29.

So a fixed wing would had needed a bigger wing and that is correct, so the variable geometry choice was correct for a 1970s aircraft
 

SSgtC

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F-15 has a lighter wing which proves Grumman was lying, the wing loading of F-15 is lower than the F-14.
That doesn't prove anything, really. The F-15 is not a naval aircraft. It wasn't designed to survive the repeated pounding of a few thousand of the controlled crashes that the Navy insists on calling a landing. Beef up the Eagle for shipboard use (as was proposed) and it gained a couple thousand pounds and would routinely get spanked in dogfights by even early Tomcats.
 

sferrin

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I wouldn't say "failure of the F401 engine", more like deliberate termination/cancellation of the F401 engine. Representative Les Aspin wanted to emulate Sen. Proxmire, and led the charge to kill the F401 with the cry that "The TF30 is good enough!"; this was in 1974. Five years later, with the USN losing a bunch of Tomcats due to engine problems, he criticized that "The Navy bought a Turkey, not a Tomcat!" but never admitted his role in the problem. I will grant you that the F100 had it's share of development problems that likely would have been shared with the F401, but the F401's more "pushed" performance meant finding some problems before the F100 did (I know of at least two cases of this).

If I sound a bit bitter about Rep. Aspin, it's because the cancellation of the F401 led to my getting laid off from Pratt & Whitney and an eight-month period of unemployment.
While you're right, the F401 wasn't all sunshine and roses either. Having both test engines fail their 60 hour tests in the same week was a huge black eye for the program. Then there's the fact that the Air Force honestly wanted to do their level best to fuck Naval Aviation in general and the Tomcat in particular. So they accepted reliability levels that they knew the Navy wouldn't just so they could stop funding the development needed to fix it. Why would they do that? Because to put it bluntly, Air Force pilots could divert to thousands of air fields when their engines shit the bed, while for the Navy, it was Carrier or Bust
They could have addressed the problem in the early 80s with the F101:


EdQQWMXUYAMnTUi.jpg
 
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sferrin

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F-15 has a lighter wing which proves Grumman was lying, the wing loading of F-15 is lower than the F-14.
That doesn't prove anything, really. The F-15 is not a naval aircraft. It wasn't designed to survive the repeated pounding of a few thousand of the controlled crashes that the Navy insists on calling a landing. Beef up the Eagle for shipboard use (as was proposed) and it gained a couple thousand pounds and would routinely get spanked in dogfights by even early Tomcats.
F-15N. Turned out no better than the F-14.

"During the development phase of the Eagle, the US Navy was instructed in July of 1971 to take a look at a possible navalized version of the Eagle, provisionally designated F-15N. At that time, the Navy was perfectly happy with its Grumman F-14A Tomcat, which was then in its flight test phase, and was less than enthusiastic about a "Sea Eagle".

The navalized F-15N was estimated to weigh some 2300 pounds more than the USAF F-15A. The Navy was unhappy about the fact that the F-15N aircraft would be unable to carry or launch the AIM-54A Phoenix long-range missile. Inclusion of this missile would have increased the weight even further. Consequently, the F-15N proceeded no further than the concept stage."
 

Mirage4000

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F-15 has a lighter wing which proves Grumman was lying, the wing loading of F-15 is lower than the F-14.
That doesn't prove anything, really. The F-15 is not a naval aircraft. It wasn't designed to survive the repeated pounding of a few thousand of the controlled crashes that the Navy insists on calling a landing. Beef up the Eagle for shipboard use (as was proposed) and it gained a couple thousand pounds and would routinely get spanked in dogfights by even early Tomcats.
That is not necesarilly the only posibility.

The F-14 was designed with VG wings for two main reasons: first it had low thrust to weight ratio and second it needed low speed flight approach during landings.

The F-15 like the MiG-29 could be navalized, however both later fighters have higher thrust to weight ratios.

On the early Mig-29K they had fewer modifications and the aircraft was pretty good.

Su-27 added canards to reduce the low speed approach to the carrier, on later MiG-29K the wing was modified and increased in size (similar to what grumman claimed) to be able to compete with Su-33 at low speed approach.

The variable geometry offered two main advantages, first at low sweep angles the wing has the highest lift possible and at high sweep the lowest drag at high speed, for a jet with low thrust to weight ratio that improves its max speed thanks to lower drag.

The advantages of the F-14 with fixed wing are seen on the MiG-29K and Su-33.

F-15 has a wing to dogh fight with a relatively higher landing speeds than F-14
 
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aim9xray

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@Mirage4000, that chart might offer a more accurate comparison of the F-14 and the F-15 if it depicted comparable models - the F-14A and the F-15A , say of 1975. You'll find that the F-15A has 2,000 lbs less internal fuel, F-100-PW-100 engines, lower performance APG-63 radar, and four Sparrows (not AMRAAMs). Absolute takeoff and landing distance of the F-14 is on the order of 300 feet/100m. Yes, catapulted and arrested, but certainly an every-day operational capability that the Eagle (as built) can never achieve. (Well OK, the F-15E can probably trap without ripping the tailhook out. Once.)
 

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@Mirage4000 actually, the F-14 was designed to have a combat thrust-to-weight ratio of better than 1:1. Using the F401 engines as originally planned for the production version (original F-14B) would have given the F-14 56,180 pounds of thrust at a combat weight of just over 52,000 pounds. The VG wings had nothing to do with low thrust to weight ratios. Rather, it was too provide the Tomcat with excellent handling characteristics in all flight regimes at all speeds.

And again, there really is no advantage to a fixed wing F-14 over a VG one. In fact, VG aircraft have multiple advantages over fixed wing fighters. But they also cost more, both to buy and maintain. So you need a damn good reason to justify the cost. The Navy had that reason (needing both excellent low and high speed handling)
 
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Mirage4000

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@Mirage4000 actually, the F-14 was designed to have a combat thrust-to-weight ratio of better than 1:1. Using the F401 engines as originally planned for the production version (original F-14B) would have given the F-14 56,180 pounds of thrust at a combat weight of just over 52,000 pounds. The VG wings had nothing to do with low thrust to weight ratios. Rather, it was too provide the Tomcat with excellent handling characteristics in all flight regimes at all speeds.

And again, there really is no advantage to a fixed wing F-14 over a VG one. In fact, VG aircraft have multiple advantages over fixed wing fighters. But they also cost more, both to buy and maintain. So you need a damn good reason to justify the cost. The Navy had that reason (needing both excellent low and high speed handling)
Let me explain if you do not agree lets settle to agree to disagree.

the F-14 with fixed wing basically is a MiG-29 or Su-27, aerodynamically speaking the Russian aircraft blend all the F-14, F-16 and F-18 features.

Variable geometry wings allow for high lift at low swept angles, thus at landings and take offs they offer enough lift to have a low AoA when landing at lower speeds.

At high speeds they have higher swept so they produce less drag.

However they also have problems of moving the center of lift and gravity when sweeping the wings, this adds weight, solutions like the wing gloves with deployable strakes like F-14A means extra weight.

On Su-33 the added canard lowered the speed and AoA of Su-27, on MiG-29K (they increased the wing as Grumman said would had happened to the fixed wing F-14) the result was a better fighter.


Su-35 can fire an AIM-54 equivalent, like very likely a fixed wing F-14 would had done.


Grumman settle for Variable geometry wings because of the low landing speeds it could allow and the very low drag once it swept its wings at the max angle of sweep.


I mean the main factor was landings since the F-14 is a very heavy aircraft, so it is hard to make it fly low and slow, but as it sweeps its wings it becomes more stable even if it uses the wing glove planes.


F-14 was a great plane no doubt about it, but nowadays Rafale represents a better solution as a naval aircraft, and same is the hornet.

The Hornet pretty much is an F-15 despite its wing and intake differences
 

Mirage4000

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The Hornet pretty much is an F-15 despite its wing and intake differences

The Hornet is pretty much an A-7 despite its wing and intake differences.
to understand what i mean you have to see these factors.

F-14A was the most produced and made of the F-14 variants flying with TF-30s.
The most modern variants never were produced in high numbers, the B was a conversion and the D were very few manufactured.

The F-14 was very expensive aircraft, so newer modifications would had mean added price.

F-15 and F-18 were from Mc Donnell douglas, of course they are different machines, the F-15 was designed to fly faster thus its intakes have variable geometry intakes ramps.

Its wing was designed for relatively high speeds retaining good maneouvrability at 700-1100km/h.

The Hornet has a high swept strake (LEX) to generate lift and create vortices for the lower swept part of the wing, so it is designed for lower speeds with a more complex wing.


When I said it is an F-15 type i did not mean is the same type of aircraft, but its basic configuration is a F-15 type for lower speeds and higher AoA.

its bubble canopy, its highly perched cockpit like F-15, its side by side engines, its twin vertical fins are similar to F-15, of course they are a different aircraft, but on F-18E you start to see those aircraft resamble each other in basic layout.
1622211802617.png

F-18E replaced F-14 simply because as maintainance is concerned, the Hornet demands less for its wing than F-14.

On January 14, 1969, the Navy announced the award of the contract for the VFX fighter, now designated F-14, to Grumman. The Navy bought 583 F-14As through 1988 and procured 55 F-14Ds (a new model) over the five-year period from 1988 to 1992. Consistent with its capability, the F-14D is expensive, with a projected average unit price tag of about $74 million [1988 dollars].

So it is very possible that F-14 with F-15 wing was not enough but a wing with LEX as on F-18 and MiG-29 were better solutions for a naval fighter.

Of course the F-18E could not replace the F-14 because the Hornet was a light fighter and even upgraded as a F-18E the Hornet has more emphasis in multirole missions.

The F-14 has a more comparable aircraft in Su-33 which uses a fixed wing and a very similar configuration.
 
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Archibald

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Since the B-1A flew in 74 it is a shame the DFE couldn't happen earlier for both USAF and Tomcat... did the B-1A had any kind of priority (before Carter canned it in June 1977) ?
 

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You could make a Tomcat with the B-1's F101 engines. Its wider, which would make low drag back end design harder, but its higher bypass ratio means lower cruise fuel consumption so it would fly further and be good for loitering CAP type missions. You'd need to use the afterburner more to go supersonic and in dogfights, but I think the overall tradeoff would be acceptable.
 

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It would look like a F-15B except with TF30 engines that suck. Maybe it would motivate the USN to provide better engines ?
They were quite motivated IOTL. But the failure of the F401 engine, and then the Ford and Carter-era defense cutbacks, meant re-engining was off the table until the F-14A+ program was started up in 1981. The former meant there wasn't a suitable engine available, given the ongoing headaches the Air Force was having with the F100; the latter meant there was no money to find a new engine anyway.
This is a sad but true fact of USN procurement. The USN has been repeatedly saddled with bad engines. Though the TF30 stands out as the absolute worst of the lot.
There's the J40 which wrecked/nearly wrecked several aircraft programmes but thankfully never reached the fleet.
 

Mirage4000

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lets settle to agree to disagree.
We're going to have to since I'm really getting tired of the shifting goal posts
Let me explain my self better.

The F-14 belongs to the late 1960s early 1970s aviation trend of using Variable Geometry wings.
In example we have MiG-23, Mirage G8, Tornado, Su-17/20/22, Su-24, F-111, Tu-22M, B-1B and later Tu-160


Variable geometry wings do have a problem, they are difficult to maintain because they are fixed to the fuselage with a rod or pivot
1622245376539.png

this structure requieres more maintainance, than a regular wing


1622245467750.png

So while technically a F-14 with better engines could compete with F-15, its maintainance time and availability was going to be lower.


Let us remember the Russians built close to 4000 MiG-23M/ML fighters, but since the 1990s, all were decomissioned in most countries, even in Russia.

To answer that you have to see, the F-14 as well as the MiG-23 were fighters that means with better engines in both aircraft, the structure was going to be put into more stress more and more time.

On Panavia Tornado since it is a interceptor well that was not as bad, on Su-24 or Tu-22M for example that was no trouble they are not dogfighters, so maintainance demands are of lower fatigue.

Early MiG-23s suffered troubles with the wing and were limited to lower G forces than late MiG-23s.

So at the end the decission by Grumman to use variable geometry wings did backfire at them.

Like the MiG-23 they needed to retire it.

On B-1B you have tiny canards near the nose of the aircraft, Su-33 took the idea for controlability and ride on Su-34.
on B-1B once the wings swept back the tiny canards help the ride and controllability.

If you ask me from my personal opinion what F-15 could had replaced the F-14 i would have said this, but this flew many years later

1622246159082.png

So to finish is not that the F-14D was not a excellent fighter, but it was too expensive and at the end affordability is a factor.

On F-14A the TF-30 was due to affordability, and the factor despite the tomcat is called a dogfighter, it real niche was of an interceptor, as such was the less agile of the teen fghters due to high maintainance, so due to high maintainance it was better to fly the F-14 as an interceptor and not as a dogfighter.
F-18E then was a better and more affordable solution; by using TF-30 the Variable geometry allowed lower drag so it compete with F-15 despite having lower thrust.

But the reality is in retrospect variable geometry wing is the reason F-14 was retired and we still have F-15EX going to be manufacture in the 2020s despite F-14 flew for the first time only a year ahead of F-15.

It is sad but it is the truth



“Back in the 1960s there was a need to vary the airplane’s geometry,” says Captain Don Gaddis of Naval Air Systems Command, a former Tomcat pilot and current program manager for its replacement, Northrop Grumman’s F/A-18 Hornet. On the F/A-18, “we’ve learned how to optimize the wing design so that the aircraft can carry out its functions” without changing geometry.

 
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Manuducati

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Mirage4000, I'll answer more thoroughly later if I can, but you seem to forgot that requirements dictate the design, not the other way around.

Thread 'USN VFX Competition (Alternatives to the F-14)' https://www.secretprojects.co.uk/threads/usn-vfx-competition-alternatives-to-the-f-14.229/

All but one of the VFX proposals had a VG wing. Except Rockwell, all the contenders and the Navy thought a fixed wing design couldn't met all requirements. You can design a fixed wing with low speed handling and long range endurance. You can have one optimal for high speed interception. But one just can't do both as efficiently. F-15N couldn't do it. Super Hornet may have replaced the Tomcat but it's performances are simply not a match. It's cheaper and requires less maintenance, but lacks the range and speed that were (at least partially) due to the VG wing.

If you look at the NATF , A-X and A/F-X proposals, a good proportion of them had variable geometry wings as well. And those were late 80's and 90's technology.
Thread 'Navy AX and A/F-X projects' https://www.secretprojects.co.uk/threads/navy-ax-and-a-f-x-projects.2150/

Lack of success on the export market is due to high price and few countries had both the needs (large country, high threat scenario) and the money for the Tomcat.
 

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The problem here is the Tomcat weapon system of radar, computer and missiles was a severely expensive element of the whole.

So even had a fixed wing option won the contest, the expense of the aircraft would not be lower enough to lure other buyers.
 

kaiserd

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As mentioned above both Grumman, their competitors and the US Navy looked at fixed wing alternatives to the F-14 (in Grumman’s case literally a fixed wing equivalent of their F-14 design), and (apart from NA and their fixed wing design, which didn’t do well in the evaluation/ design competition) everyone thought the swing-wing designs (in particular the design that became the F-14) was better re: meeting the requirements set out by the US Navy at that time.
Hence there was no better fixed wing design waiting in the wings for alternative selection (navalised F-15s, more advanced F-4 developments etc. were not as good match for the US Navy’s requirements, and in the F-15s case would have had to gain weight and drag, would have had to lug Phoenix’s around etc.)

And a alternative worse winning design (also likely no cheaper) would seem unlikely to win more export orders than the F-14 did; the F-14s weapon system (radar & Phoenix missiles) were very pricey and seen as quite US Navy “defend the carrier” role tailored. Makes sense that the slightly cheaper but still very expensive F-15 was (rightly) seen as more flexible in the fighter role and that the few countries shopping at that level generally opted for the F-15 (pre-revolution Iran being the obvious exception).

And I don’t follow the apparent strain of arguments above re: fixed wing F-14 equals Su-27 or MIG-29 so must defend fixed wing F-14, etc. To me it sounds like a lot of false equivalents and faulty premises being proposed.
 
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Mirage4000

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Mirage4000, I'll answer more thoroughly later if I can, but you seem to forgot that requirements dictate the design, not the other way around.

Thread 'USN VFX Competition (Alternatives to the F-14)' https://www.secretprojects.co.uk/threads/usn-vfx-competition-alternatives-to-the-f-14.229/

All but one of the VFX proposals had a VG wing. Except Rockwell, all the contenders and the Navy thought a fixed wing design couldn't met all requirements. You can design a fixed wing with low speed handling and long range endurance. You can have one optimal for high speed interception. But one just can't do both as efficiently. F-15N couldn't do it. Super Hornet may have replaced the Tomcat but it's performances are simply not a match. It's cheaper and requires less maintenance, but lacks the range and speed that were (at least partially) due to the VG wing.

If you look at the NATF , A-X and A/F-X proposals, a good proportion of them had variable geometry wings as well. And those were late 80's and 90's technology.
Thread 'Navy AX and A/F-X projects' https://www.secretprojects.co.uk/threads/navy-ax-and-a-f-x-projects.2150/

Lack of success on the export market is due to high price and few countries had both the needs (large country, high threat scenario) and the money for the Tomcat.
1622290341365.png

when the F-14 sweeps its wing at very low Angle has a very high aspect ratio wing (20 degrees on takeoff). so it generates its lift at very low AoA

1622290532499.png

At low sweep angles the F-14 can generate greater lift (20 degrees on takeoff) , let us consider F-14 has a wing span much longer than F-15.
1622290835720.png
So at low speeds and for landing in a Carrier, yes F-14 has a better wing but Variable geometry requieres heavier structure.

On F-18 the wing is of much more complex because it generates very powerful vortices generating high lift plus it has wing leading edge control devices, generating a smaller wing.


1622291030068.png


The wing you see on the F-14 with fixed wing is similar to the one of F-15, however F-18 has a very complex wing with LEX basically.

In the late 1960s when F-14 was designed, LEX were in their infancy, and the fashion was Variable Geometry wings.

The F-14 was designed upon a theoretical concepts that were later surpassed by YF-17 and later F-18.

the reason the F-18E can not replace the F-14 is not aerodynamics but the size it has, the Hornet F-18C was a light to medium size aircraft while the F-14 was a very heavy aircraft.

Besides in real combat the AIM-54 was not succesful with american aircraft.


So you are right for a 1960s the F-14 was succesful, but for a late 1970s it was not, once LEX or canards were exploited you get fighters like Rafale or F-18 which were quiet agile and in the case of Rafale it can use Meteor which is more advanced than AIM-54 and much lighter so you do not need a heavy aircraft to carry meteors.
 
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sferrin

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The F/A-18 is most of a Mach number slower than the Tomcat as well. Mach 1.8 vs Mach 2.41 (and still accelerating, and that was with TF30s). Yes, we know they limited the Ds to Mach 1.88 and removed/deleted the glove vanes but that was by choice. If they'd had a need for the higher speed they could have kept it. You don't have that option with the Hornet.
 

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The F/A-18 is most of a Mach number slower than the Tomcat as well. Mach 1.8 vs Mach 2.41 (and still accelerating, and that was with TF30s). Yes, we know they limited the Ds to Mach 1.88 and removed/deleted the glove vanes but that was by choice. If they'd had a need for the higher speed they could have kept it. You don't have that option with the Hornet.
And the proposed ST21 was projected to have a top speed of over Mach 2.5. Hell, the NATF (Naval F-22) was going to be north of Mach 2.25 (and was also going to have a swing wing incidentally)
 

Manuducati

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So at low speeds and for landing in a Carrier, yes F-14 has a better wing but Variable geometry requieres heavier structure.
That's true only if you keep ignoring all the requirements. You could not at the time (and not sure it has changed) design a fixed wing that could perform well at low speed AND high speed AND with low drag AND long endurance AND good bring back capability. If you want to add all those characteristics with a fixed wing, you have to add a mix of lifting devices, folding mechanisms, more powerful engines, more fuel etc... so leading to a bigger aircraft.
The key point is that VG allows conflicting requirements to be met. With a fixed wing, you have to choose or to lower the objective.
Again that was the conclusion of almost everyone at the time. And none of the aircrafts introduced after it could perform as well in every single area. You can have simpler/lighter/cheaper (and better in one domain or another) but you have to give up some of those requirements.

On F-18 the wing is of much more complex because it generates very powerful vortices generating high lift plus it has wing leading edge control devices, generating a smaller wing.
A wing that is very draggy, can't sustain high speed and can't go very far. Really effective only from stall speed to transonic regime. Again not the same requirements.

The wing you see on the F-14 with fixed wing is similar to the one of F-15, however F-18 has a very complex wing with LEX basically.

In the late 1960s when F-14 was designed, LEX were in their infancy, and the fashion was Variable Geometry wings.

The F-14 was designed upon a theoretical concepts that were later surpassed by YF-17 and later F-18.

the reason the F-18E can not replace the F-14 is not aerodynamics but the size it has, the Hornet F-18C was a light to medium size aircraft while the F-14 was a very heavy aircraft.
No aircraft from the YF-17 to the F/A-18E/F ever had to (nor could) fill all the requirements of the Tomcat. How can you surpass something you don't match?
You can't claim you are the best triathlon athlete if you can't swim (even if you were the best runner and cyclist out there).
And as I noted earlier, several 90's proposals to replace the Tomcat had a VG wing as well, and were in the same size/weight category to accomplish similar missions. BTW on the carrier deck, the Super Hornet is only shorter by less than three feet and narrower by less than one.

Besides in real combat the AIM-54 was not succesful with american aircraft.


So you are right for a 1960s the F-14 was succesful, but for a late 1970s it was not, once LEX or canards were exploited you get fighters like Rafale or F-18 which were quiet agile and in the case of Rafale it can use Meteor which is more advanced than AIM-54 and much lighter so you do not need a heavy aircraft to carry meteors.
I don't see how this relates to the thread subject. And again neither the F/A-18 nor the Rafale (a wonderful machine IMHO) does match the F-14 requirements.
 

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Besides in real combat the AIM-54 was not succesful with american aircraft.
Because the US Navy never used the Phoenix against the threat it was designed for. The AIM-54 was not meant as an anti-fighter weapon and fared poorly against maneuvering targets. It was meant to shoot down Soviet MPAs and bombers. Had the USN ever engaged Soviet Naval Aviation, I feel pretty confident that the Phoenix would have racked up an impressive number of kills
 

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So at low speeds and for landing in a Carrier, yes F-14 has a better wing but Variable geometry requieres heavier structure.
That's true only if you keep ignoring all the requirements. You could not at the time (and not sure it has changed) design a fixed wing that could perform well at low speed AND high speed AND with low drag AND long endurance AND good bring back capability. If you want to add all those characteristics with a fixed wing, you have to add a mix of lifting devices, folding mechanisms, more powerful engines, more fuel etc... so leading to a bigger aircraft.
The key point is that VG allows conflicting requirements to be met. With a fixed wing, you have to choose or to lower the objective.
Again that was the conclusion of almost everyone at the time. And none of the aircrafts introduced after it could perform as well in every single area. You can have simpler/lighter/cheaper (and better in one domain or another) but you have to give up some of those requirements.

On F-18 the wing is of much more complex because it generates very powerful vortices generating high lift plus it has wing leading edge control devices, generating a smaller wing.
A wing that is very draggy, can't sustain high speed and can't go very far. Really effective only from stall speed to transonic regime. Again not the same requirements.

The wing you see on the F-14 with fixed wing is similar to the one of F-15, however F-18 has a very complex wing with LEX basically.

In the late 1960s when F-14 was designed, LEX were in their infancy, and the fashion was Variable Geometry wings.

The F-14 was designed upon a theoretical concepts that were later surpassed by YF-17 and later F-18.

the reason the F-18E can not replace the F-14 is not aerodynamics but the size it has, the Hornet F-18C was a light to medium size aircraft while the F-14 was a very heavy aircraft.
No aircraft from the YF-17 to the F/A-18E/F ever had to (nor could) fill all the requirements of the Tomcat. How can you surpass something you don't match?
You can't claim you are the best triathlon athlete if you can't swim (even if you were the best runner and cyclist out there).
And as I noted earlier, several 90's proposals to replace the Tomcat had a VG wing as well, and were in the same size/weight category to accomplish similar missions. BTW on the carrier deck, the Super Hornet is only shorter by less than three feet and narrower by less than one.

Besides in real combat the AIM-54 was not succesful with american aircraft.


So you are right for a 1960s the F-14 was succesful, but for a late 1970s it was not, once LEX or canards were exploited you get fighters like Rafale or F-18 which were quiet agile and in the case of Rafale it can use Meteor which is more advanced than AIM-54 and much lighter so you do not need a heavy aircraft to carry meteors.
I don't see how this relates to the thread subject. And again neither the F/A-18 nor the Rafale (a wonderful machine IMHO) does match the F-14 requirements.
There are things about history we have to recall.

F-14 stopped production in the early 1990s, F-15 continue production and even now they build F-15s for the USAF.

Production and profit wise F-15 is more succesful.

F-15N was never built, why? simple the F-15 was also expensive and for the US navy it was not needed to replace an expensive fighter with a variant that was not even manufactured and could have ended as expensive.

However they needed a fighter it could supplement (by supplement they mean a fighter could replace the F-14 in missions it was expensive to be used) so it was born the F-18 which is basically a smaller and simplier F-15N.

The F-18 was in dogfights a better machine, and it was cheaper, the F-14A was the cheapest variant because it was flown as an interceptor, and it was an interceptor, the Variable geometry wing stucture like in MiG-23ML or MiG-23MF would have been damaged if flown at 9Gs all the time.

MiG-23ML the most agile MiG-23 in its latest sub-variant the MiG-23MLD was limited to 8.5Gs.

F-14 was not different, so the F-18 with a fixed wing was the ideal aircraft to dogfight.

So the variable Geometry wing was and is a structure that requires much more care and maintainance.

On a Fighter like Tornado ADV which is an interceptor, it is fine, but the F-14 was advertized as a dogfighter, the Variable geometry wing was not the right wing, so I will tell you something we like about F-14, these are its variable geometry wings, I am a big fan of F-14, believe me but I know F-14 was doomed when they decided to use variable geometry wings for a dog fighter.

On MiG-23 users, the MiG-21 could do same at a cheaper price so they retired the MiG-23s and kept the MiG-21s and MiG-29s.

F-18C can use meteors, the mistake we assume is you need a heavy missile like AIM-54, that was a 1980s and 1990s weapon, the reality newer AIM-120Ds and Meteor can be used by even Gripen a light fighter.
1622328057467.png


Now I will tell you why I think the single seat fixed wing F-14 in my opinion as technologies matured would had survived probably until the 2010s at least in the US navy.

Adding leading edge wing divices would had replaced some of the needs for a swing wing and later newer radars engines and weapons would had allowed to continue production into the 2000s to the fixed wing F-14.

The mistake was the F-14A was a 1960s solution for a problem was solved with better radars and missiles.

Su-35 with Meteors would have been a much more credible succesor, I mean a Su-33 with Meteors and AESA.

But let us remember everything has a price, so the F-18E is a cheaper alternative to F-14, the americans only need a Meteor type of Missile and with AIM-9X the F-18 will replace the F-14 completly
 
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Mirage4000

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With a pair of meteor AAMs, flying out of CdG under control of a Hawkeye... Rafale come close at least.
Rafale is a much better solution than F-14, it is smaller, its canards allow low speed landings and Meteor is more agile and lighter than AIM-54, of course it is an aircraft of newer generation but the F-14 as beautiful as it was, it was delicate, the wing box and pivot mechanisms of the its variable geometry wing doomed it to be an interceptor and the Americans made a mistake by not adapting a newer missile like Meteor, but a meteor type of missile means hornet can replace F-14

1622329743922.png

Remember France did study Variable geometry wings but the Rafale finished using canards, the Mirage 2000 and F1 were deemed cheaper and lighter, Variable geometry wings are a solution more for attack aircraft
 
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Manuducati

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Mirage4000, again you chose to ignore what were the Navy requirements and not to stick to that era possibilities.
Every single proposal (except one) came to the same conclusion!

From Home of the M.A.T.S. :
During the design process, some 9,000 hours of wind-tunnel testing were performed on some 2,000 different configurations and nearly 400 combinations of air inlets and exhaust nozzles! In 1968 the design studies of the Grumman engineers concentrated on 8 layouts before the E version became the winning design (See table below). Thoughts during the design process incorporated the behaviour during high speed (supersonic) flight, supersonic combat ceiling performance, trouble-free engine performance, engine growth potential and subsonic longitudinal stability. The fixed-wing version was rejected because of its weight, carrier suitability and because of its low-altitude performance.

Everybody, including McDonnell Douglas with its model 225 took that way. By the way the Hornet is technically more an enlarged F-5 than a simplified F-15, remember the original design is from Northrop, not from McDonnell Douglas.
Was the VG wing the best for dogfight? No. The best for high speed? No. The best for endurance? No. The best for weight? No. The best for any specific domain? Probably not. But it is the only one to permit to perform reasonably well in every aspect. And that was the requirement.

And please stop comparing the F-14 to the F-15. Different missions, different planes.
You can judge a machine by its ability to accomplish the mission(s) it was designed for, not by its sales figures. The LEM did successfully put men on the moon. Was it a failure because it wasn't exported? Poor comparison for a poor deduction.


I don't see why you keep comparing the AIM-54 with the Meteor and AIM-120D to invalidate the Tomcat success. Those newer missiles are almost 50 years late to the party to do so. You can't judge the F-14 (or any other aircraft) with today standard. It's like saying the P-51D was a failure because it wasn't supersonic and didn't have towed decoys...
Anyway it takes more than strapping a couple long range missiles to the Super Hornet to make it a true F-14 successor. You may know that when the SH was imposed to the Navy, it was said that the AAM AIM-152 would compensate for the lost Phoenix capacities, totally ignoring the fact that the SH radar wasn't able to see as far as the missile could shoot. But that doesn't matter as the missile program was shelved as well. Even now with the AIM-120D, the SH still hasn't got the autonomy to maximise its effectiveness and the speed to give the missile better kinetic energy and probability of kill.


To answer the thread question, yes a fixed wing Tomcat could have been done but either:
- Heavier (which, combined with the P&W engine fiasco would certainly lead to a program end).
- Same weight but with lowered performances (and vastly inferior to the F-15 so probably no export sales).

And as Zen stated:
The problem here is the Tomcat weapon system of radar, computer and missiles was a severely expensive element of the whole.

So even had a fixed wing option won the contest, the expense of the aircraft would not be lower enough to lure other buyers.
 
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Mirage4000

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Mirage4000, again you chose to ignore what were the Navy requirements and not to stick to that era possibilities.
Every single proposal (except one) came to the same conclusion!

From Home of the M.A.T.S. :
During the design process, some 9,000 hours of wind-tunnel testing were performed on some 2,000 different configurations and nearly 400 combinations of air inlets and exhaust nozzles! In 1968 the design studies of the Grumman engineers concentrated on 8 layouts before the E version became the winning design (See table below). Thoughts during the design process incorporated the behaviour during high speed (supersonic) flight, supersonic combat ceiling performance, trouble-free engine performance, engine growth potential and subsonic longitudinal stability. The fixed-wing version was rejected because of its weight, carrier suitability and because of its low-altitude performance.

Everybody, including McDonnell Douglas with its model 225 took that way. By the way the Hornet is technically more an enlarged F-5 than a simplified F-15, remember the original design is from Northrop, not from McDonnell Douglas.
Was the VG wing the best for dogfight? No. The best for high speed? No. The best for endurance? No. The best for weight? No. The best for any specific domain? Probably not. But it is the only one to permit to perform reasonably well in every aspect. And that was the requirement.

And please stop comparing the F-14 to the F-15. Different missions, different planes.
You can judge a machine by its ability to accomplish the mission(s) it was designed for, not by its sales figures. The LEM did successfully put men on the moon. Was it a failure because it wasn't exported? Poor comparison for a poor deduction.


I don't see why you keep comparing the AIM-54 with the Meteor and AIM-120D to invalidate the Tomcat success. Those newer missiles are almost 50 years late to the party to do so. You can't judge the F-14 (or any other aircraft) with today standard. It's like saying the P-51D was a failure because it wasn't supersonic and didn't have towed decoys...
Anyway it takes more than strapping a couple long range missiles to the Super Hornet to make it a true F-14 successor. You may know that when the SH was imposed to the Navy, it was said that the AAM AIM-152 would compensate for the lost Phoenix capacities, totally ignoring the fact that the SH radar wasn't able to see as far as the missile could shoot. But that doesn't matter as the missile program was shelved as well. Even now with the AIM-120D, the SH still hasn't got the autonomy to maximise its effectiveness and the speed to give the missile better kinetic energy and probability of kill.


To answer the thread question, yes a fixed wing Tomcat could have been done but either:
- Heavier (which, combined with the P&W engine fiasco would certainly lead to a program end).
- Same weight but with lowered performances (and vastly inferior to the F-15 so probably no export sales).

And as Zen stated:
The problem here is the Tomcat weapon system of radar, computer and missiles was a severely expensive element of the whole.

So even had a fixed wing option won the contest, the expense of the aircraft would not be lower enough to lure other buyers.
The fixed wing does not mean automatically less capable.

Variable geometry wings was a late 1960s and late 1970s fashion.

In order to see why F-14 chose variable geometry and F-15 fixed wing, see the high aspect wing gives lower speed at landings if the fighter landed on a carrier with a heavy load
1622376324273.png

if you look at the specifications you see the F-14 has a shorter landing run and wider wing span but actually it has higher wing loading than the F-15.

In order to interpret this you have to see for the F-15 to have a shorter landing run it will need a bigger wing to have lower landing speed and shorten the landing run.


So what they mean by heavier wing is not that the variable geometry wing mechanism are lighter than fixed wings because they are not.

But for a fixed wing with lower aspect ratio like F-14 with fixed wing and higher sweep angle, they would had have fit a bigger wing, see that F-15 actually has more wing area than F-14.


LEX do increase lift and reduce wing area, F-15 could not fit a long LEX but F-18 did and So MiG-29 and Su-27, on Su-33 even Sukhoi adapted canards.

The wing design Grumman used on the fixed wing F-14 study was much less advanced than the wing with LEX F-18 or Su-27 have.

the advantages of variable geometry wing for F-14 were eliminated when it comes to dogfighting due to fatigue issues.


Mc Donnell was the creator of F-15 and the manufacturer and partial designer of F-18, so F-18 was the substitute
of F-15N; adding a better wing design to F-18 rather than using the same wing design of F-15N.


So the conclusion is for landings a higher aspect ratio and a 20 degrees of angle of swept wing, yes F-14s variable geometry wing was better, but at the long run, variable geometry killed the F-14 program due to more advances in aerodynamics such as LEXes, later electronics and later missile technology.
 
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