scholastic question

I only knew three knids of air fighters which vertical tail has fuel tank.
The three jet fighter was F-111 Aardark Su-27/30/35 Flanker and F-18E/F Superhornet. Who knew more?
The thoughts I have is why other fighter doesn't has fuel tank in certical tail? We knew that every inch space in a fighter is really valuable. But some fighters such as F-22 Raptor, which projective square of vertical tail was bigger than any other fighter I have known, why it doesn't use vertical tail's space to load fuel so that to increase combat radius?

I didn't know that any of those did have fin tanks emile, but I can tell you that the Tornado IDS and GR.4 does have a fin tank as well, except, according to the source I just checked, not in the F.3 ADV version, which seems strange to me. Maybe that source is wrong and all Tornadoes have them?

WAYNOS:
That all I have known just according to some cutaways I have got. An instance is in Jane's All World's Aircraft 2002-2003, in which a cutaway of SuperHornet showed fin tank.
Yeah, The Tornado you said remends me of which also has fin tank probably. But it is important to get evidence to prove. I think there are some others still been lost.

[edit on 13-11-2005 by emile]

Emile, the source I checked was a book which is a history of the Tornado written by Bill Gunston. In that book the cutaway of the IDS shows a fin tank while the cutaway of the ADV does not. Janes 1998 editon however states that the ADV does have a fin tank, so there it is. It appears that it was just left off the drawing as it had already been shown on the previous one.

I can't find anything about vertical fin fuel tanks in those planes. In fact the F/A-18E/F had a fuselage extension added to put an extra fuel tank in. I used to live around FB-111s which were the same as the F-111 structurally, and I don't remember anything about them having a fuel tank in the tail.

If I remember right all the tornado A/c Varients had fin tanks but all use this tank first so normally by the end of the runway this tank is empty (only holds 440Kg's) and full of fuel vapours.

Now this is not a good idea as any damage to the fin from flak , cannon shells etc. would lead to an explosion so the tank is "purged" with nitrogen (inhert gas) so as to remove this hazard.

As to the F3, it normally taxi's on the ground with the wings fully swept back so you have to be very careful when refuelling the A/c on the ground as it is possible to choose from the ground refuel panel the order of filling the 14 internal tanks so it is very easy to fill all the rear group of tanks first and sit the thing on its tail (seen it done and had to sort it out afterwards!)

By the time the F3 reach's the runway the fin tank is empty so it can sweep its wings forward and reconfigure itself for take off( flaps, slats etc.)

The first part of my answer could explain why not too many A/c have a "wet" fin or tail and also it might have something to do with altering the C of G of the A/c in flight but in modern A/c the flight computers would compensate for this!

So it could be just down to minimising the risk of having a big vapour filled target at the rear of the A/c!!!!!

Hope this is of some use to you emile

Sv Out........!

sv, I am confused by part of your answer. Why do Tornadoes taxi with their wings sswept back as this puts more weight to the back of the plane and makes it more likely to tip over, surely? Also why can it only sweep its wings forward when the fin tank is empty, surely the more weight it can put forward while the fin tank is full the better?

Having read through my post I can see I have not clarifyed it enough. The GR 1 and GR4's ( which always use the fin tank) are parked and taxied with the wings fully forward and almost never taxi with the wing's swept back as this could put the C of G of the A/c (depending on what stores it has on the various pylons i.e underwing tanks, chaff/flare pod, skyshadow ECM pod, sidewinders etc.) to the rear of the main u/c which might cause the A/c to sit on its tail.

When I worked on the F3 it was normally parked and taxied with the wings swept fully to the rear as the A/c has a extended radome and a heavier radar package which keep the C of G of the A/c in front of the main u/c.

However this was before the F3 had outboard pylons fitted as the original F2/F3 did not have any provision for chaff or flare pods to be fitted. This was rectified during GW part 1 by fitting fare dispensers to the engine doors and GR1 outboard pylons to the F3 wings and hardwiring them in!!!! ( I know all about this because I was part of the team who was given the task of making the thing work!.....22 A/c modded in 2 weeks from scratch!)

So the modded F3 might not be able to taxi with the wings back....unless the fin tank is not used so this might be where waynos's info about the F3 fin tank might be coming from!

I am going to have a lie down now as my head hurts!

Sv Out.....!

Wouldnt a fin tank effect "in air" flight...weight distribution wise? Therefore making them irrelevant on some aircraft because they would effect flight due to the aircraft design.

You would burn through the fin tank in no time flat if you have one. The vertical finds are so small that you could hold MAYBE a couple hundred pounds of fuel in there. You'd burn through that before you even got airborne with an afterburner take off. It really wouldn't affect you unless you took off with it full and burned it off in flight. They weight distribution would change your CG as you were flying. But since it'll be empty when you get airborne it won't affect you.

[edit on 11/13/2005 by Zaphod58]

Also the Tornado's fin tank will get empty before it raise in air, but I think it's still worth retain it. The hundreds pounds fuel is to supply you taking off, is it?!
I should remember the Tornado's fin tank is so big that should have fin tank. compare with it, Aardvark's vertical tail is really smaller but still retain it, so I think because a spaces of swing wing fighter inside is more cabined, almost of swing wing fighters have fin tank.
Now we have four fighters which has fin tank, has more?

Originally posted by emile
I only knew three knids of air fighters which vertical tail has fuel tank.
The three jet fighter was F-111 Aardark Su-27/30/35 Flanker and F-18E/F Superhornet.

Since when is there a fule tank in the veritcal fin of an F-111 Aardvark or an F/A-18 E/F? On theEF-111 Raven, there is an ECM pod on top of the fin, but not a fule tank. However, that pod is ONLY on the EF-111 Electronic Warfare aircraft.

Tim

Yeah, F-111 has two nickname, all of F-111's nickname was Aardvark, except EF-111 which nickname was Raven. But the fuel tank in vertical fin I pointed was not that pod which obviously on top of fin. I also wondered that measeurement of F-111's fin was not as bigger as Tornado, why has fuel tank in it, but a square F-22 Raptor's vertical fin is really so big that should be designed fuel tank in it.

Maybe the F-11 fin isn't as small compared to the Tornado as you think? Look at this picture, but remember to allow for perspective.

And remember "Its not how big it is, its what you do with it that counts"

hehe……, Waynos, because of prespective, I have to say these two is almost same at most. Prespective was a weapon you given me

Now let's move on more difficult question.
We all know that when an aircraft do a transonic to supersonic flying which will cause shock wave. I actually don't know whether be use "shock wave" in English to direct it.
Then, we know that the design of Raptor's air-intake used a theory called CARET. I don't know what does CARET mean, I just know that describe an aircraft use this kind of air-intake as Raptor used can fly as skiing on ice as ride on shock wave. This air intake using English named Surfing Intake by myself but not formal and scientific
Next, I've known that CARET airintake which Raptor used just a kind of two-dimension Surfing wave Intake, wheres JSF F-35 used is three-dimension.
So just according to the design of air-intakes, that F-35 is more superior than F-22.
Now, which master here wish teach me
1) what's the full spelling of CARET,
2) what is that meaning?
3) which kind of air-intakes F-22 and F-35 used is more superior?
4) This really difficult one that need more people knowledgable is what's the principle with difference of those air-intakes which is able to let F-22 or 35 to fly as ride a horse as ride on supersonic shock wave.
Every one teach me will be my teacher, who please look me as a bookish student.

[edit on 16-11-2005 by emile]

[edit on 16-11-2005 by emile]

I am too sad that most people zealous discuss hypersonic aircraft whether exist or not regardless US just start to test 5M degree aircraft, but no one research this realistic and serious problem :shk: