An alternate F-11 Tiger

[bobtdwarf]

So the all weather fighter with sparrows light launch weight:
from 27,800 lbs
-2000 drop tank fuel weight
-500 drop tanks
=25300 (8000 lbs fuel, fraction ~32 %)
Extrapolating stall speed ~ 137 kts
Minimum safety with an AB launch maybe 3 = 140kts
Deduct about 100 kts from the H-8
= 40 kts wod

With 23k lbs maximum launch weight in zero natural wind, the Tiger would need a tanker around. Not unusual*, just a bit cumbersome.

* I've seen contradicting information, some say that USN practice is/was to top off launching aircraft from a tanker anyway.

which is still pretty amazing for the 250 sqft wing ST. If I understand you figures the number I have to work with is 25400? So at 250 sqft. that is a wing loading of 101.2.. that drops to 82.65 at 310 sqft. with the additional weight from the wing factored in and 75.84 at 340 with the wing weight added in. IIRC the A-4 is launching with something like 77 but will have to check...


EDIT: Checked at 20k and 272 wing area (listed in the linked source in a post) that is a rounded up 74, at 260 the stock wing area that is a rounded up 77. As is pointed out below not always a useful number but I have yet to find anything lifting off an H-8 with over that 77 or maybe 78..

 

[bobtdwarf]

The 98J versions were all with 250 sqft wing and the J79?

Yes.

and some of that weight is in the WTF category of changes/amendments to the aircraft we have no information on.. and some of them look to be more fuel.. which is super curious to me since the J-79 was 250 pounds lighter than the J-65. As I recall I don't remember Corky mentioning any frame strengthening

 

[orlovsky]

The 98J versions were all with 250 sqft wing and the J79?

Yes.

and some of that weight is in the WTF category of changes/amendments to the aircraft we have no information on.. and some of them look to be more fuel.. which is super curious to me since the J-79 was 250 pounds lighter than the J-65. As I recall I don't remember Corky mentioning any frame strengthening

The little information in the SACs shows a lengthening from 44 to 48 ft. That alone will require some weight and maybe allow for more fuel. No idea how large the j65 was with AB?

 

[H_K]

@bobtdwarf One can’t really compare wing loadings across aircraft with completely different wing shapes. So the A-4’s numbers aren’t useful.

Even the FJ-3 / FJ-4 aren’t good comparables… just take a look at the FJ-3, -3M, and -4… similar wing shapes and wing loadings but the stall speeds are all over the place. Turns out their wings have very different lift coefficients due to wing thickness, slats etc. As for the F11F, it had 20% higher wing loading than the FJ-3M but still achieved the same stall speeds!

Best to extrapolate from the existing F11F, or look at close analogs like the Etendard IVB.

 

[H_K]

The little information in the SACs shows a lengthening from 44 to 48 ft. That alone will require some weight and maybe allow for more fuel. No idea how large the j65 was with AB?

More like from 45 to 48ft. The extra 3 feet were in the Super Tiger’s longer nose. The fuel tanks were the same as the F11F, just the addition of the belly tank in place of the guns.

The J65 is 184” x 41”, somewhat shorter than a J79 (207” x 38.3”), but the J65 didn’t extend all the way to the tail so the J79 was able to fit without changing overall length.

 

[orlovsky]

I would have said the nose in the sac drawings is maybe 1.5 ft longer, so the remaining 2 ft or so would be for engine length. But those drawings lack detail...

 

[bobtdwarf]

The 98J versions were all with 250 sqft wing and the J79?

Yes.

and some of that weight is in the WTF category of changes/amendments to the aircraft we have no information on.. and some of them look to be more fuel.. which is super curious to me since the J-79 was 250 pounds lighter than the J-65. As I recall I don't remember Corky mentioning any frame strengthening

The little information in the SACs shows a lengthening from 44 to 48 ft. That alone will require some weight and maybe allow for more fuel. No idea how large the j65 was with AB?

at its widest 41.5 inches and about 184 inches long. Point of comparison the TF-41 turbofan in the A-7E is 185 long...and 50 pounds heavier, have thought about it for a replacement engine.

 

[bobtdwarf]

@bobtdwarf One can’t really compare wing loadings across aircraft with completely different wing shapes. So the A-4’s numbers aren’t useful.

Even the FJ-3 / FJ-4 aren’t good comparables… just take a look at the FJ-3, -3M, and -4… similar wing shapes and wing loadings but the stall speeds are all over the place. Turns out their wings have very different lift coefficients due to wing thickness, slats etc. As for the F11F, it had 20% higher wing loading than the FJ-3M but still achieved the same stall speeds!

Best to extrapolate from the existing F11F, or look at close analogs like the Etendard IVB.

I usually use the FJ4 since I am using its wing shape...

EDIT: I also generally use wing loading as a quick check if it might work; have yet to find anything with a wing loading over 77 that stood a chance of taking off from an H-8

 

[bobtdwarf]

The little information in the SACs shows a lengthening from 44 to 48 ft. That alone will require some weight and maybe allow for more fuel. No idea how large the j65 was with AB?

More like from 45 to 48ft. The extra 3 feet were in the Super Tiger’s longer nose. The fuel tanks were the same as the F11F, just the addition of the belly tank in place of the guns.

The J65 is 184” x 41”, somewhat shorter than a J79 (207” x 38.3”), but the J65 didn’t extend all the way to the tail so the J79 was able to fit without changing overall length.

the additional fuel were in "cheek" tanks in place of the guns, outer engine nacelles from what I have gathered.
Also the F-11 illustrated in the SAC sheet is the early short nose which explains the length difference.

 

[bobtdwarf]

I would have said the nose in the sac drawings is maybe 1.5 ft longer, so the remaining 2 ft or so would be for engine length. But those drawings lack detail...

the super Tiger did have about a 1 foot fuselage plug in it to improve performance and yeah the SAC image is the early development model of the Tiger with the short nose.

 

[H_K]

the super Tiger did have about a 1 foot fuselage plug in it to improve performance

Source? I haven’t seen any evidence of this

 

[bobtdwarf]

the super Tiger did have about a 1 foot fuselage plug in it to improve performance

Source? I haven’t seen any evidence of this

it is in Corky's book talking about the modifications to the #2 prototype...might be 10 inches in the text

 

[H_K]

it is in Corky's book talking about the modifications to the #2 prototype...might be 10 inches in the text

OK I see. This is the 13.25in tailcone extension visible in the pictures below. The fuselage itself wasn’t modified in any major way and the overall length was unchanged.

(Top picture: prototype #1 with short tailcone, bottom picture: prototype #2 with 13.25in tailcone extension)

 

[bobtdwarf]

it is in Corky's book talking about the modifications to the #2 prototype...might be 10 inches in the text

OK I see. This is the 13.25in tailcone extension visible in the pictures below. The fuselage itself wasn’t modified in any major way and the overall length was unchanged.

(Top picture: prototype #1 with short tailcone, bottom picture: prototype #2 with 13.25in tailcone extension)

cool, it has been awhile since I read it.

 

[orlovsky]

it is in Corky's book talking about the modifications to the #2 prototype...might be 10 inches in the text

OK I see. This is the 13.25in tailcone extension visible in the pictures below. The fuselage itself wasn’t modified in any major way and the overall length was unchanged.

(Top picture: prototype #1 with short tailcone, bottom picture: prototype #2 with 13.25in tailcone extension)

But no explanation where the +2000 lbs empty weight come from?

 

[bobtdwarf]

it is in Corky's book talking about the modifications to the #2 prototype...might be 10 inches in the text

OK I see. This is the 13.25in tailcone extension visible in the pictures below. The fuselage itself wasn’t modified in any major way and the overall length was unchanged.

(Top picture: prototype #1 with short tailcone, bottom picture: prototype #2 with 13.25in tailcone extension)

But no explanation where the +2000 lbs empty weight come from?

that IS strange... the long nose was 244 pounds heavier than the early shorties between the nose and ballast. I know they added a hard point to the wing and stressed it for greater load, but that should NOT consume a ton.. unless they reinforced the whole bird to take a higher G load? Very odd..

 

[orlovsky]

The nose, the radar (ballast), the wing strengthening, and maybe a new electrical system and new wiring... higher weight, so maybe stronger landing gear...
Those changes can escalate. The F-4 went from early ~26k to ~32k empty in the F-4S.
But it would be interesting to have a little more detail.

 

[bobtdwarf]

The nose, the radar (ballast), the wing strengthening, and maybe a new electrical system and new wiring... higher weight, so maybe stronger landing gear...
Those changes can escalate. The F-4 went from early ~26k to ~32k empty in the F-4S.
But it would be interesting to have a little more detail.

did a compare between the FJ4 and FJ4B which had additional avionics and a stronger wing.. FJ4 empty 13,210 pounds 4B empty 13,778.. let me check the A-4.. A4A 8400 A4E 9624.. more detail would be fantastic.. I personally would love it if they reinforced the airframe so it could handle 7.5G's

 

[H_K]

The nose, the radar (ballast), the wing strengthening, and maybe a new electrical system and new wiring... higher weight, so maybe stronger landing gear...
Those changes can escalate.

My read is the basic Super Tiger conversion (98J-1) added ~400lbs, the multirole 98J-5 added another ~800lbs, and the all-weather 98J-2 with Sparrow added another ~800lbs.

The 400lbs for the 98J-1 probably came from all the small airframe changes to optimize for supersonic flight (e.g. longer tailcone, added wing blivets, dorsal launcher for Aim-9s etc) even if the J79 engine itself was 250lbs lighter.

The 800lbs for the J-5 probably came mostly from strengthening and adding air-to-ground capability (including 2 new wing pylons and heavier drop tanks), as the original F11F didn’t have a very strong airframe (6.5g load factor and low max. landing weight). Plus further aerodynamic refinements (larger nose & canopy), more avionics compared to the very basic F11F (APQ-50 radar, improved navigation, radios etc).

The 800lbs for the J-2 probably was mostly avionics, including ~250lbs for Sparrow III capability, plus some more for an improved electrical system etc.

 

[bobtdwarf]

The 98-L figures as a comparison

 

[orlovsky]

Here’s what I found in Corky Meyer’s book… looks like the Super Tiger proposals gained quite a lot of weight over time, about 2,000lbs (!). Not really surprising as other designs like the F-8A-> F-8E also saw weight growth. But not good for flying from light carriers.

Gross TO weight - Fuel - Useful load = Empty weight

F11F (late production models):
21,280lbs - 6,650 -1,100 = 13,530 lb empty
98J-1 (original Super Tiger proposal):
22,730 lbs - 8,150 - 610 = 13,970 lbs (+ 450lbs)
98J-5 (as flown):
23,250 lbs - 7,840 - 610 = 14,800 lbs (+830lbs)
98J-2 (all weather fighter):
27,800 lbs - 10,110 - 2,120 = 15,570 lbs (+830lbs)
98J-7 (2-seat all weather fighter)
23,350lbs - 7,300 - 500 = 15,530 lbs (-40 lbs)

For the above I had to estimate useful load, as follows:

300 lbs for pilot + gear + oil + trapped fuel (500lbs for two seater 98J-7)

800lbs for 4x 20mm guns + ammo (F11F)
or 300lbs for 2x Sidewinders (98J-1, -2 and -5)

98J-2 only: 1,040lbs for 2x Sparrows + launchers and 470lbs for 2x 150-gal tanks

Note that none of the 98J designs had cannon as standard. Instead this space was used for an optional (removable?) belly tank for approx ~180 gallons of fuel (1,200lbs). The gun pack was optional.

Coming back to the weight figures if I read them correctly (please correct), the quick and cheap reengined "McTiger" would be a 98j-1 with the gun and 2 Sidewinders. So -1200 fuel +800 guns = 22330 lbs, fuel fraction ~31 %. Can operate from CVS and maybe even the 112ft HMAS Melbourne steam catapult (problem will shift to arresting). 4 sidewinders should be doable.

The sparrow version 98j-2 without a gun and only internal fuel would be 25300 lbs as mentioned before: mls ~140kts, requiring 40 kts wod on a CVS, about 25 kts wod with the longer BS4 so requiring Centaur class and upwards.

The 98j-2 @27800 lbs (or with a gun and less fuel about 27400 lbs): mls close to 150 kts. Centaur class with longer BS4 probably too marginal, no problem for Audacious or Clemenceau class.

For comparison: F-8A, internal fuel + sidewinders had about the same weight (~27500) and would be ~140 kts mls.

 

[bobtdwarf]

found part of the weight! Those ventral fins... not going to drop a lot of weight but some as they turned out not the needed to maintain stability. They also are on the J-7 two seater.

Also 10k pounds of fuel?!

 

[H_K]

Also 10k pounds of fuel?!

Yes. 6,650lb standard (F11F) + 1,200lb in belly tank (in lieu of guns) + 1,950lb in 2x 150gal drop tanks. Total 9,800lb.

Assuming that’s old JP4 fuel @ 6.5lbs/gal so add ~4.5% for JP5 @ 6.8lbs/gal, which gives you 10,240lbs… close enough.

 

[bobtdwarf]

Here’s what I found in Corky Meyer’s book… looks like the Super Tiger proposals gained quite a lot of weight over time, about 2,000lbs (!). Not really surprising as other designs like the F-8A-> F-8E also saw weight growth. But not good for flying from light carriers.

Gross TO weight - Fuel - Useful load = Empty weight

F11F (late production models):
21,280lbs - 6,650 -1,100 = 13,530 lb empty
98J-1 (original Super Tiger proposal):
22,730 lbs - 8,150 - 610 = 13,970 lbs (+ 450lbs)
98J-5 (as flown):
23,250 lbs - 7,840 - 610 = 14,800 lbs (+830lbs)
98J-2 (all weather fighter):
27,800 lbs - 10,110 - 2,120 = 15,570 lbs (+830lbs)
98J-7 (2-seat all weather fighter)
23,350lbs - 7,300 - 500 = 15,530 lbs (-40 lbs)

For the above I had to estimate useful load, as follows:

300 lbs for pilot + gear + oil + trapped fuel (500lbs for two seater 98J-7)

800lbs for 4x 20mm guns + ammo (F11F)
or 300lbs for 2x Sidewinders (98J-1, -2 and -5)

98J-2 only: 1,040lbs for 2x Sparrows + launchers and 470lbs for 2x 150-gal tanks

Note that none of the 98J designs had cannon as standard. Instead this space was used for an optional (removable?) belly tank for approx ~180 gallons of fuel (1,200lbs). The gun pack was optional.

Coming back to the weight figures if I read them correctly (please correct), the quick and cheap reengined "McTiger" would be a 98j-1 with the gun and 2 Sidewinders. So -1200 fuel +800 guns = 22330 lbs, fuel fraction ~31 %. Can operate from CVS and maybe even the 112ft HMAS Melbourne steam catapult (problem will shift to arresting). 4 sidewinders should be doable.

The sparrow version 98j-2 without a gun and only internal fuel would be 25300 lbs as mentioned before: mls ~140kts, requiring 40 kts wod on a CVS, about 25 kts wod with the longer BS4 so requiring Centaur class and upwards.

The 98j-2 @27800 lbs (or with a gun and less fuel about 27400 lbs): mls close to 150 kts. Centaur class with longer BS4 probably too marginal, no problem for Audacious or Clemenceau class.

For comparison: F-8A, internal fuel + sidewinders had about the same weight (~27500) and would be ~140 kts mls.

as I say in the post above this one... that 27,800 includes 10,000 pounds of fuel.. so that gives you 3000 pounds that you could leave off on the longer BS4 reasonably

 

[bobtdwarf]

Also 10k pounds of fuel?!

Yes. 6,650lb standard (F11F) + 1,200lb in belly tank (in lieu of guns) + 1,950lb in 2x 150gal drop tanks. Total 9,800lb.

Assuming that’s old JP4 fuel @ 6.5lbs/gal so add ~4.5% for JP5 @ 6.8lbs/gal, which gives you 10,240lbs… close enough.

the cheek tanks that replace the guns are listed as a total of 59 gallons on the SAC. I am assuming that the big jump in fuel is larger wing tanks here.. Tiger carried 192 gallons TOTAL between the 2 and FJ carried 173 gallon EACH so the Tiger at the same wing thickness could probably take a larger tank. In any case that gives 3000 pounds of fuel we can leave off on some BS4 launches to get her off the deck

 

[H_K]

the cheek tanks that replace the guns are listed as a total of 59 gallons on the SAC. I am assuming that the big jump in fuel is larger wing tanks here… Tiger carried 192 gallons TOTAL between the 2 and FJ carried 173 gallon EACH so the Tiger at the same wing thickness could probably take a larger tank

No on both counts. The guns are placed in the belly and replaced with a belly tank… nothing to do with the small cheek tanks.

The wings are completely different in both thickness and chord (FJ-4: 6% x 114” MAC, F11F: 6% to 4% x 98” MAC)… the FJ-4’s wing has a lot more volume as it is not optimized for supersonic speeds. No way to magically engineer more fuel in an F11F (sadly).

 

[bobtdwarf]

the cheek tanks that replace the guns are listed as a total of 59 gallons on the SAC. I am assuming that the big jump in fuel is larger wing tanks here… Tiger carried 192 gallons TOTAL between the 2 and FJ carried 173 gallon EACH so the Tiger at the same wing thickness could probably take a larger tank

No on both counts. The guns are placed in the belly and replaced with a belly tank… nothing to do with the small cheek tanks.

The wings are completely different in both thickness and chord (FJ-4: 6% x 114” MAC, F11F: 6% to 4% x 98” MAC)… the FJ-4’s wing has a lot more volume as it is not optimized for supersonic speeds. No way to magically engineer more fuel in an F11F (sadly).

Warbird Registry - F-11 Tiger - A Warbirds Resource Group Site

The Warbird Registry is source of information documenting all aircraft used by the worlds military that managed to survive that service. This section covers jet propelled aircraft.

www.warbirdregistry.org

We might be using belly differently... the guns are on the intakes to me. But that is the standard Tiger. I have seen a drawing where the guns look to be on the underside of the nose and the drawing I have of the ST has the guns more on the side of the intakes and staggered with one gun about a foot forward of the other.

Not saying that there isn't a belly tank just trying to clarify.. fair point on the wing. Earlier in the thread a "tin pot dictator" version with a J-52 and more guns in the nose was discussed.

 

[bobtdwarf]

I love the amount of detail this thread has teased out about the Tiger and just about everything!

 

[bobtdwarf]

holy hell I may have been misreading this drawing for years! What I have thought was the rearward gun on the side may not be the gun port but the breech.. sorry I am losing the word for where the spent cartridge exits..EDIT: Ejection port... can't brain today I have the dumb

EDIT: Not MAY but HAVE.. crap



They looked to be increasing the chord on the 98-L

Another EDIT: Now I am wondering where the hell the reputation for being a poor gun platform came from? I thought it might be because the guns were more widely placed than the F-8 but that was based on a bad misreading of the drawing! It looks to me at least (and take that as you will after admitting I misread a drawing), like the gun are at least as close together as on the F-8.

 

[H_K]

We might be using belly differently... the guns are on the intakes to me. But that is the standard Tiger. I have seen a drawing where the guns look to be on the underside of the nose

This is probably the drawing you saw… clearly shows the guns and ammo boxes in the belly.

 

[bobtdwarf]

We might be using belly differently... the guns are on the intakes to me. But that is the standard Tiger. I have seen a drawing where the guns look to be on the underside of the nose

This is probably the drawing you saw… clearly shows the guns and ammo boxes in the belly.

That is one of the ones I have seen. Though it doesn't match the pictures of the actual aircraft(it does but not what I would use belly for which is why I was clarifying, I usually use belly for the very bottom of the main fuselage) .. they may have truncated the view for ease as it omits the intakes, which would just shorten up the belts going to the boxes. Noses matches up pretty close to the white and grey Dreamtime image above... which would be the belly side of the intakes, even seems to match up on being slightly elevated. But definitely the ammo boxes and guns being removed would open up a lot of room for a tank

EDIT: This post has bothered the hell out of me for days.. I will leave it untouched but damn! It reads like I had a seizure while writing it.
Yeah the ammo boxes are in the belly.. I originally thought the cannon were on the outer edge of the intakes and just never "saw" it; you get something in your head and you just stop seeing it.

 

[bobtdwarf]

anyone got a scaled head on image of an F-8 handy? Could you check the distance between the guns right to left?

Also dig the difference in squat between the two pics.. not all of the blue angel one is from flat tires.

 

[bobtdwarf]

The nose, the radar (ballast), the wing strengthening, and maybe a new electrical system and new wiring... higher weight, so maybe stronger landing gear...
Those changes can escalate.

My read is the basic Super Tiger conversion (98J-1) added ~400lbs, the multirole 98J-5 added another ~800lbs, and the all-weather 98J-2 with Sparrow added another ~800lbs.

The 400lbs for the 98J-1 probably came from all the small airframe changes to optimize for supersonic flight (e.g. longer tailcone, added wing blivets, dorsal launcher for Aim-9s etc) even if the J79 engine itself was 250lbs lighter.

The 800lbs for the J-5 probably came mostly from strengthening and adding air-to-ground capability (including 2 new wing pylons and heavier drop tanks), as the original F11F didn’t have a very strong airframe (6.5g load factor and low max. landing weight). Plus further aerodynamic refinements (larger nose & canopy), more avionics compared to the very basic F11F (APQ-50 radar, improved navigation, radios etc).

The 800lbs for the J-2 probably was mostly avionics, including ~250lbs for Sparrow III capability, plus some more for an improved electrical system etc.

I want to thank you for all the information you have provided, you and @orlovsky have both brought a great deal of information and detail that I at least have found invaluable.

 

[bobtdwarf]

Oy! Just reread post 391! Now that is some hot garbage of borderline gibberish on my part.

 

[Dynoman]

This is probably the drawing you saw… clearly shows the guns and ammo boxes in the belly.

Photos taken at Valiant Air Command Museum, Titusville, Florida.

 

[bobtdwarf]

This is probably the drawing you saw… clearly shows the guns and ammo boxes in the belly.

Photos taken at Valiant Air Command Museum, Titusville, Florida.

those are fantastic pics! It blows me away how badly I misread the drawing in post 389. I thought that the top cannon in these pics was the forward most gun and that the second one was the elongated oval towards the bottom on the side of the 3 view, which made sense to me with the apparently bad info about the cheek tanks being used in place of the guns and that she was not a very good gun platform.. the guns would have a broader spread.

Definitely the ammo boxes are in the belly... probably a decent access panel down there for replacing them. Edit: What was confusing to me was thinking the cannon were in what I think of as the belly(the bottom third of the main fuselage), when many people use "belly" to describe the whole underside of the aircraft... just having a bad brain day lol

 

[Dynoman]

Here's a portside view of the guns with the door closed. Note the DARPA Shape Sonic Boom Demonstrator F-5E behind the wing.

 

[bobtdwarf]

hey.. been busy but had a thought about the "tin pot dictator" version..built on historic F-11 airframes.

If Grumman kept the avionics in the F-5E/F-8U/A-4E range that leaves enough room in the nose for a pair of cannon so you could use that big belly tank. Use a J-52 408 as the power plant to get the better SFC without dropping the power... and you have like an early '70s AMX.

Edit: The dorsal AIM-9's give everyone acid stomach, they probably would work but that null drag zone they sit in if you look at it gives you a nice bit of room for a spine of avionics or fuel of about that size that could be pretty useful. 10k pounds of fuel would give it some decent legs

 

[Archibald]

My suggestion: if you need a J52 with afterburner, ask the Swedes for the Viggen engine. Through the civilian JT8D, it was exactly that: an improved, afterburning J52.
Hmmm, a Skyhawk - Tiger - Viggen trio with the same basic engine, now that would be something to behold.

 

[bobtdwarf]

My suggestion: if you need a J52 with afterburner, ask the Swedes for the Viggen engine. Through the civilian JT8D, it is exactly that: an improved, afterburning J52.

That would be nice but as usual I am thinking no AB on this to keep her speed in the Mach 1.1-1.2 range because of that US policy on restricting super fast jets in parts of the world. But given the Mirage is available I am reasonably sure that it will get the sale because of that policy.