F-14 vs F-15 vs F-16

[Messy1]

I agree. Love the soundtrack! Queen One Vision, Twisted Sister, good stuff. Far fetched movie, but I thought it was cool in it's day.

[Matt308]

Don't forget the AESA also has comm and offensive capabilities. Add to your typical multiple target paint and track possibilities for the following:

Direct and jam resistant air-to-air communications for joint tactical information sharing.

Beem steered RF jamming capability.

Radar tracking and data spoofing.

Potential for offensive avionics destructiion/interruption via directed RF emmissions.

AESA is a game changer. And everybody wants it. Even Eurofighter won't get it until Tranche III.

[Soren]

Originally Posted by DerAdlerIstGelandet

Because Soren says so, I don't know....



Quit it now Joe! What do you know? You only have actual real world flight experience in high speed twin engined fighter jets, that does not come close to "real world book knowledge"!

Fine, since you're of the opinion I have nothing to contribute with I'
ll shut up.

[drgondog]

Originally Posted by Soren

Fine, since you're of the opinion I have nothing to contribute with I'
ll shut up.

You frequently have a lot to contribute

[Soren]

Originally Posted by Bill

I would start with L/D but that would be silly me.

Oh, I guess the below doesn't qualify as L/D related:

" However the higher AR of the F-14's wing gives it more lift and less drag pr. area, which is also what allows it to land on a carrier while the F-15 would be completely incapable of that because of it's higher stall speed."

Originally Posted by Bill

If you wish to maintain the AR of the F-14 in transonic to supersonic is greater - prove it (it will be tough).

Hmmm... I guess this didn't make sense to you:

"The wing sweep action works automatically on the F-14, adjusting according to the flight mode of the a/c. If entering a tight turn the sweep is varied automatically to give the best results. This gives it better turn performance."

But then again, what do I know, I'm not an aerodynamics expert who bases all his comments on "facts" like you are...

As for span loading, again:

"Aspect ratio and planform are powerful indicators of the general performance of a wing, although the aspect ratio as such is only a secondary indicator. The wingspan is the crucial component of the performance. This is because an airplane derives its lift from a roughly cylindrical tube of air that is affected by the craft as it moves, and the diameter of that cylindrical tube is equal to the wingspan. Thus a large wingspan is working on a large cylinder of air, and a small wingspan is working on a small cylinder of air. The smaller cylinder of air must be pushed downward by a greater amount in order to produce an equal upward force; the aft-leaning component of this change in velocity is proportional to the induced drag. Therefore a large downward velocity is proportional to a large induced drag.

The interaction between undisturbed air outside the cylindrical tube of air, and the downward-moving cylindrical tube of air occurs at the wing's tips, and can be seen as wingtip vortices."

Oh but then again the above is just opinion based, not "facts" like you rely on.

I bow humply to your superior knowledge.

[Soren]

Double post

[Soren]

Originally Posted by drgondog

You frequently have a lot to contribute

Yeah, opinions and guesswork in your opinion..

Even when I've made it clear that while I know a lot on the subject I am no expert in airplane aerodynamics, you're still more busy hammering at me, patronizing me and calling me names, instead of actually trying to figure out what it is I'm saying (Incase my terminology is incorrect) and then providing what you know after that. No, you just have to throw in the patronizing remarks as well pull up out-of-context phrases from old arguments to make it look like you're the sh*t and I'm stupid even to be debating with you.

I truly wish one could have a friendly FACT based debate with you Bill, but it has been impossible for me so far, even when letting you know that I'm noting every word you write as educated information or guesswork, cause you completely ignore what I write, even purposely misunderstanding some of the clear cut out fact based information I provide. Now I'd love to be educated when wrong, but I can do without being ridiculed for doing nothing but reading what you write and responding with what I know.

Afterall I think everyone everywhere should remember that unless you're directly involved with the subject at hand then you ONLY know what you've read about it. Math is fact based, but again you only know what you've read about it.

[drgondog]

Originally Posted by Soren

Oh, I guess the below doesn't qualify as L/D related:

" However the higher AR of the F-14's wing gives it more lift and less drag pr. area, which is also what allows it to land on a carrier while the F-15 would be completely incapable of that because of it's higher stall speed."

Hmmm - the span of the F-14 is 38 ft swept. To you that means in transonic to supersonic config. The area is 565 ft^^2 in both configs.

AR for the sweptback wing is 38*38/565= 2.55

AR of the 'extended wing' at low speeds is 64*64/565 = 7.2

The span of the F-15 is 42 ft. The area is 608ft^^2
AR = 42*42/608 = 2.9 ~ 13% better than the F-14 from transonic up to max speed (which is higher than F-14)

The span of the F-16 is 32 ft. The area is 300ft^^2
AR = 3.4 ~ 33% better than the F-14 from transonic up to max (which is slightly lower than F-14)

Lift Loading at 1g. All higher g lift loading at equivalent g's are proportional, except that F-14 not designed for 9 G's

Nominal loaded weight for F-14 (not max Take Off) is 61K
61000/565 = 118 #/ft sq

Nominal loaded weight for F-15 is 44,500
44500/608 = 73 which is ~ 67% of the F-14

Nominal loaded weight for the F-16 is 26,500
26500/300 = 88 which is ~ 21% of the F-14

Is your thesis that the way you wish to discuss ACM capability is in the pattern up to 350 kts?


Hmmm... I guess this didn't make sense to you:

I think I pointed out that the extended wing was subsonic and maybe transonic to supersonic transition. Above that the extension would be questionable - but I'm willing for you to prove that the F-14 deployed at all speeds and explain the automatic mechanism for deployment and retraction - then explain how the F-14 navigated between supersonic and subsonic ac shifts from a stability poit of view?

"The wing sweep action works automatically on the F-14, adjusting according to the flight mode of the a/c. If entering a tight turn the sweep is varied automatically to give the best results. This gives it better turn performance."

So, your thesis is that the F-14 will not lose energy like a drunken sailor by 'popping it's wings at say 800 kts?

But then again, what do I know, I'm not an aerodynamics expert who bases all his comments on "facts" like you are...

That is correct Soren.

As for span loading, again:

"Aspect ratio and planform are powerful indicators of the general performance of a wing, although the aspect ratio as such is only a secondary indicator. The wingspan is the crucial component of the performance. This is because an airplane derives its lift from a roughly cylindrical tube of air that is affected by the craft as it moves, and the diameter of that cylindrical tube is equal to the wingspan. Thus a large wingspan is working on a large cylinder of air, and a small wingspan is working on a small cylinder of air. The smaller cylinder of air must be pushed downward by a greater amount in order to produce an equal upward force; the aft-leaning component of this change in velocity is proportional to the induced drag. Therefore a large downward velocity is proportional to a large induced drag.

The interaction between undisturbed air outside the cylindrical tube of air, and the downward-moving cylindrical tube of air occurs at the wing's tips, and can be seen as wingtip vortices."

So, Soren. A U-2 has a 103 ft wingspan, an aspect ratio of 10.6. Is your thesis that the smaller 'stream tube' of the F-14 as evidenced by either the 38 ft swept wing or 64 ft extended wing is superior in efficiency to the U-2?

Would you further advance that induced drag of the U-2 is greater? What opinion would you care to advance regarding L/D of the antiquated, non computer controlled, wing of the U-2 in contrast to the F-14?

Would you say that the tip vortex strength of a U-2 is greater than the F-14?

Take the arguement in the opposite direction - compare the 'smaller stream tube U-2' to the B-29 which had a higher AR and 40% MORE span than the U-2. What are your conclusions about the efficiency and the relative strength of the tip vortices - which one would you prefer to land behind?

Last, the wing span difference between a U-2 and a B-17 are only a couple of inches off. What do you want to say about the same stream tube and it's validity to the wing efficiencies?

Oh but then again the above is just opinion based, not "facts" like you rely on.

Soren, which of the three examples makes sense to you and which one do you wish to base your 'stream tube' thesis on? BTW for comparable span and geometry lift loading is a better determinant for judging relative tip vortex strength

I bow humply to your superior knowledge.

Ok

[DerAdlerIstGelandet]

Originally Posted by SoD Stitch

Okay, let's take a look at the two radar systems in question:

AWG-9: For it's time, the most powerful airborne radar system in the world; able to track up to 24 targets at a time, and launch missles at 6 of them at one time. Range well in excess of 100 nm. However, it is based and built using analog technology from the '60's, was maintenance intensive, and was completely incapapable of being used in an a2g mode (which is why the F-14D got the AN/APG-71 digital multi-mode radar); could probably best be compared to the RP-25 Smerch radar on the later MiG-25 interceptor.

AN/APG-63(V)3: Completely digital, multi-mode AESA technology, classified range (the broadly similar radar in the F-22, the AN/APG-77, has a range "in excess of 320 miles"), multiple LRU's, can be used interchangably in both a2a & a2g modes, LPI frequency-hopping (the AWG-9 couldn't do this).

You did not need to explain that to me. I was being sarcastic.

[drgondog]

Originally Posted by Soren

Yeah, opinions and guesswork in your opinion..

Even when I've made it clear that while I know a lot on the subject I am no expert in airplane aerodynamics, you're still more busy hammering at me, patronizing me and calling me names, instead of actually trying to figure out what it is I'm saying (Incase my terminology is incorrect) and then providing what you know after that. No, you just have to throw in the patronizing remarks as well pull up out-of-context phrases from old arguments to make it look like you're the sh*t and I'm stupid even to be debating with you.

I usually hammer you only when you advance obscure references to aero theory completely out of context and frequently wrong.

I truly wish one could have a friendly FACT based debate with you Bill, but it has been impossible for me so far, even when letting you know that I'm noting every word you write as educated information or guesswork, cause you completely ignore what I write, even purposely misunderstanding some of the clear cut out fact based information I provide. Now I'd love to be educated when wrong, but I can do without being ridiculed for doing nothing but reading what you write and responding with what I know.

Afterall I think everyone everywhere should remember that unless you're directly involved with the subject at hand then you ONLY know what you've read about it. Math is fact based, but again you only know what you've read about it.

Lol. Well I have a minor in math so I haven't read as much about it as I have aero and fluid mechanics. What have you a.) read about Calculus, Vector Analysis, Differential Equations, Tensor Analysis, Matrix Theory, Chaos Theory, and Control Theory. Are you going to lecture my lack of knowledge based on 'book learning'?

As to the practical - I was actively engaged in the theoretical, and hand's on practical side of aerodynamics, aero structures, and airframe design from 1968-1975 at Lockheed, Bell and at GE. At GE I was 'on loan' as a consultant to TI for aero and structures work on the early LGB's for Mk 82-84's. At GE I was also the AFCAM Program manager in which the DoD was attempting to unify Group Technologies and Parts Classification methods to improve DoD 7000 methods Costing and Program pricing alignment for all the General Contractors.

I did everything from pioneer relaxation methodology (a math 'thingy') for potential flow models of aerodynamic pressure distributions, to NASTRAN structural models and advanced R&D. This doesn't include Co-Op work at NASA and Boeing as an undergrad.

I am pretty far removed from 'just reading about it...but you ARE correct that I have been away from it for 30 years. How long have you 'been away from it'??

What have YOU been doing to gather your credentials?

If you want to understand why we don't have friendly debates, look in the mirror as well as your posturing.

[DerAdlerIstGelandet]

Originally Posted by Soren

Fine, since you're of the opinion I have nothing to contribute with I'
ll shut up.

Oh I did not say that, you do contribute quite a bit.

I just think it is funny how you will argue with someone just for the sake of argueing, and wont back down even when you are wrong.

There have been times you argue with people who have flown specific aircraft or similar aircraft...

[Messy1]

Bill, the only thing I understood from your last post was MATH THINGY!

[Soren]

So, Soren. A U-2 has a 103 ft wingspan, an aspect ratio of 10.6. Is your thesis that the smaller 'stream tube' of the F-14 as evidenced by either the 38 ft swept wing or 64 ft extended wing is superior in efficiency to the U-2?

Nope, that's not at all what I'm saying. The U-2's wing provides more lift & less drag pr. area than the F-14's, the higher AR makes sure of that. It's the very same thing that makes the F-14's wing more efficient than either the F-15's or F-16's.

Would you further advance that induced drag of the U-2 is greater? What opinion would you care to advance regarding L/D of the antiquated, non computer controlled, wing of the U-2 in contrast to the F-14?

Bill have you at all been reading what I write ???!

No ofcourse the Cdi wont be higher for the U-2, it'll be lower, again because of the higher AR. A higher AR means a higher L/D ratio.

Would you say that the tip vortex strength of a U-2 is greater than the F-14?

Again no.

Tell me do you understand what this means:
"Aspect ratio and planform are powerful indicators of the general performance of a wing, although the aspect ratio as such is only a secondary indicator. The wingspan is the crucial component of the performance. This is because an airplane derives its lift from a roughly cylindrical tube of air that is affected by the craft as it moves, and the diameter of that cylindrical tube is equal to the wingspan. Thus a large wingspan is working on a large cylinder of air, and a small wingspan is working on a small cylinder of air. The smaller cylinder of air must be pushed downward by a greater amount in order to produce an equal upward force; the aft-leaning component of this change in velocity is proportional to the induced drag. Therefore a large downward velocity is proportional to a large induced drag."

If you do, then why are you asking me these questions ?

[DerAdlerIstGelandet]

Originally Posted by drgondog

If you want to understand why we don't have friendly debates, look in the mirror as well as your posturing.

I think that about sums it up.

Now having said that. I think that most people on this forum are intelligent eneogh to piece together the pieces and walk away from your discussions with Soren having learned something new.

In the end the discussions are rather interesting and pretty good.

[Soren]

That is correct Soren.

Well, you certainly are an arrogant fella, I'll give you that!

If you want to understand why we don't have friendly debates, look in the mirror as well as your posturing.

Oh I am so sorry for being offended when being called stupid, that is so wrong of me, I apologize Bill. You are in your full right to start an argument by calling others names, it is my job to take full responsibility for that, I mean I after all provoked you into it right ?