F-14D Cockpit
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WOW…What he said!:rolleyes:
Thanks for passing by C.
Pepe
True, once you hit the high alpha regime, you get 60% increase in lift and this is actually documented. Even if you take into account my projected STR for the A model, it’s not that far behind the Eagle. Combined with the tight TR this makes both planes a close match in the guns arena. Once you factor in the GE engines though the Eagle loses all advantage in STR up to 400-450knots. Actually the only restriction on the Turkey at this stage is the structural limit.
EDIT (just for you Pepe):
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well guys those all are subjective… why??? cause they all depend mostly on the human factor…
How many hours did the pilots had on their birds (I’m sure the tomcat pilots had way much more time in their birds meaning they new by heart how to react).
LOL 1978… and when eagles and f-16 joined the arena?Tomcats joined 1974 that is 4 years of experience
F-15 joined mid 1978 same year as the F-16… So yes comparing bricks with oranges is the same thing…
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well guys those all are subjective… why??? cause they all depend mostly on the human factor…
How many hours did the pilots had on their birds (I’m sure the tomcat pilots had way much more time in their birds meaning they new by heart how to react).
LOL 1978… and when eagles and f-16 joined the arena?Tomcats joined 1974 that is 4 years of experience
F-15 joined mid 1978 same year as the F-16… So yes comparing bricks with oranges is the same thing…
The largest operator of the F-15 is the United States Air Force. The first Eagle (F-15B) was delivered 13 November 1974.[38] In January 1976, the first Eagle destined for a combat squadron, the 555th TFS, was delivered.[38] These initial aircraft carried the Hughes Aircraft (now Raytheon) APG-63 radar.
http://en.wikipedia.org/wiki/McDonnell_Douglas_F-15_Eagle
I’m not arguing that the given example isn’t subjective, but I feel that saying two years gave the Navy time to make Super aces is an equally subjective excuse, at least imho.
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The slighty better low speed turn rate IMHO is useless because using better med-hi speed perfomance of F-15/F-16, they can climb above F-14 while they are turning. Because of the flight path projection, the turn radius on the horizontal plane is smaler than F-14’s at low speed. Higher alt + same turn radius during climbing –-> Definite advantage for F-15/16. The only advantage what F-14 have in an acting dogfight the two-man crew. Only problem that F-15 have dual seat version, which is fully capable only its EW (ECM) capabilit is different from single seat variant.
BTW haven’t you ever noticed that the most succesful jet from teenager series is the double seater F-15 if you count the specific kill ratio? During wars since 1982 only an F-15B was able to achive tripe kill during one mission in 1982, and it had more than one double kill in IAF. During Peace for Galilea and just after a months 33 air victory was gained by IAF’s F-15s by weapon usage. From 33 kill 9 was gained by F-15B. From the 24 available F-15s, only two was F-15B. This means that 8% of fleet gained the 27% or kills. (25 F-15s was bought, one was lost before 1982 and another one single seater heavily damaged which was flown by the younger Shapira.)
The sample is not huge but IMHO is very interesting. IT suggests that the king of fighters in '80s was not F-15A but F-15B. (If you do not need ECM.)
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well guys those all are subjective… why??? cause they all depend mostly on the human factor…
How many hours did the pilots had on their birds (I’m sure the tomcat pilots had way much more time in their birds meaning they new by heart how to react).
LOL 1978… and when eagles and f-16 joined the arena?Tomcats joined 1974 that is 4 years of experience
F-15 joined mid 1978 same year as the F-16… So yes comparing bricks with oranges is the same thing…
That’s the thing, isn’t it? The human factor is the single biggest factor in deciding who wins in a dogfight, not airframe (which is why these arguments to me are silly to begin with). But, they aren’t entirely subjective, nor is this comparing “bricks to oranges”; the pilots involved in example 1 had similar amounts of experience. Though not active until 1976, the F-15 had already begun participating in the ACEVAL/AIMVAL trials, for which workups began late 1975, and was involved totally from 1976-1977, through ENDEX 1978 when the pilots involved got into their forbidden fight. Of the two Tomcat crews, one pilot and one RIO had been part of the Tomcat inaugural cruse in mid 1974, pulled from F-4 Phantoms (both in the jet at 34k at the time of their “kill”), the other pilot had been selected after 2 combat cruises in the F-8 and one in the RA-5 (he was actually still part of the RA-5 community at the time). All of his Tomcat experience was ACEVAL/AIMVAL, same as the Eagle drivers. So, not all that different.
In terms of kill ratios, hell yeah the Eagle holds the best overall! I’m not trying to argue that, and I think it’s awesome that such a machine continues to fight in our arsenal. What I am saying is that the Turkey could and did more than hold its own in a dogfight when it had to. Any well flown aircraft can do amazing things, and the F-14 was no exception.
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I can vouch for only 2 things on that chart, it’s a clean configuration with 100% fuel load and it’s a TF-30 powered F-14A.
As for the analysis, i partly agree with it and the ultimate conclusion is the same, the energy advantage and sustained turn rate goes to the F-15C, while the turn radius advantage and nose authority at low speed go to the F-14A. However i don’t think we can equate the sustained turn rate based on specific excess power alone. Not in the lower part of the envelope. The higher the mach number, the more important factors are the total thrust and the ultimate G-load capability. However the lower the mach number, drag and aerodynamic efficiency become more prevalent. And….we also have comparable analysis available that can serve to adjust our data. Namely the slated F-4E diagrams. Officially, the F-14A has 20% better STR (between mach 0.4 and mach 1.1) the F-4E, which makes it similar to the “light” F-4s (17% increase of STR over the F-4E).This is what i got BTW…
(the blue line should be STR at sea level)I do not understand your line. Sustainable turn rate means, Ps = 0 at a certain turn rate. On your lines the values for F-14 are much higher as Ps = 0 line as in the first F-14 speed-turn rate (Ps) diagram. For ex at M0.8 turn rate of F-14 while Ps = 0 is about 14 deg/sec and not 18 as in your diagram.
Did I misunderstand something?
I’m still not sure about the flight level in the first and second diagram. F-15/F-16 can reach M1.4 on about 10k feet, but F-14’s variable wing maybe allows a slighty bigger top speed at low.
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To sum up, not a soul will argue that the F-15 isa masterwork of design that resulted in a proven dog fighter and interceptor. The F-16 also speaks for itself. The only issue arises when yet another person has decided Internet info means that the F-14 isn’t a comparable dog fighter. You will always guess at charts until the performance data is declassified, if ever. The most accurate thing you can say at this point is they the F-15 rules the transonic region of the fight while the F-14 owns the lower speed arena but the differences aren’t that huge. The wing of the F-14 stalls before the tunnel does. A clean or aim-9 and aim-7 armed tomcat has an insane actual wing loading.
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I do not understand your line. Sustainable turn rate means, Ps = 0 at a certain turn rate. On your lines the values for F-14 are much higher as Ps = 0 line as in the first F-14 speed-turn rate (Ps) diagram. For ex at M0.8 turn rate of F-14 while Ps = 0 is about 14 deg/sec and not 18 as in your diagram.
Did I misunderstand something?
I’m still not sure about the flight level in the first and second diagram. F-15/F-16 can reach M1.4 on about 10k feet, but F-14’s variable wing maybe allows a slighty bigger top speed at low.
The line is adjusted to account for the higher lift to drag ratio and to match the know performance when matched with an AC we do have the STR available (F-4E). We can’t guess at the performance through specific excess power only. At lower mach numbers induced drag plays ever greater role. Still i do not claim my curve to be correct. In fact it is only one of several possible curves, extrapolated through the sustained G-loads as provided and the known envelope of the slated F-4E.
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I do not understand the base of adjustment. The first F-14 diagrams shows what it shows.
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And doesn’t account for the pancake (565sqft wing model), and is inaccurate in terms of -Ps as you move behind the hump in the Ps=0 line. The chart can give you an idea of performance, but it isn’t the whole story, like I said before.
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And doesn’t account for the pancake (565sqft wing model), and is inaccurate in terms of -Ps as you move behind the hump in the Ps=0 line. The chart can give you an idea of performance, but it isn’t the whole story, like I said before.
No. Ps tells you the whole story. This is why so amazing the E-M Theory by John Boyd and Tom Chrsite. It was used illustrating AC dogfight capabilites. In the same case where an AC have bigger Ps that is the better AC in that case. End of the story.
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i love it when someone sez end of story…
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The slighty better low speed turn rate IMHO is useless because using better med-hi speed perfomance of F-15/F-16, they can climb above F-14 while they are turning. Because of the flight path projection, the turn radius on the horizontal plane is smaler than F-14’s at low speed. Higher alt + same turn radius during climbing –-> Definite advantage for F-15/16. The only advantage what F-14 have in an acting dogfight the two-man crew.
Exploiting the vertical is definitely what you should do when facing virtually any opponent in an F-15. But and this is a big BUT, it by no means assures a victory. Every displacement turn or high Yo-Yo bares the risk of losing visual contact with the enemy and when facing a pilot with an equal (presumably high) skill, actually forcing this loss of contact. Not to mention that to actually use this tactic you need to be on the opponent’s six to begin with. Try to force a vertical pass from a neutral merge and you invite a tail shot up those warm pipes when facing a plane that pitches its nose better then you.
No. Ps tells you the whole story. This is why so amazing the E-M Theory by John Boyd and Tom Chrsite. It was used illustrating AC dogfight capabilites. In the same case where an AC have bigger Ps that is the better AC in that case. End of the story.
LOL
Dude, Boyd theory is just one way of looking at things. It’s by no means the only one or the best at that. It has it’s advantages for sure, but to quote another authority on ACM (one with more aerial kills then Boyd ever had), “the energy advantage determines when will the engagement start, the angles advantage determines how it will end”.Now, as to why specific excess power isn’t the whole story and with a concrete example of the F-14A. It is documented in video materials and photography that during air shows the F-14A was constantly being able to do a full 360 at minimum turning radius of about 1000ft without losing air speed in about 20 second. That is a circle the length of about 6300ft. The sustained turning rate in these examples is about 18deg/s. Doing a 6300ft circle in 20 seconds translates to about 315ft per second or about 185-190 nautical miles per hour (knots) air speed. Performing this at airshow means this is practically at sea level wish would mean a mach number of about 0.28. Now take a look at he Ps values around mach 0.3. Based on Ps alone, the F-14A should be able to pull no more then 10 or 11deg/s at best. Let’s presume that the aircraft performing this aerobatics at airshows are probably running an extremely light configuration with only 10% internal fuel. The empty weight of an F-14 is 43,735 lbs. Maximum internal fuel capacity is 16,200 lb. If our chart describes a clean AC with a 100% fuel tank that would account for a 59935lbs Tomcat. The airshow Tomcat would be 45355lbs in comparison. 75-76% the total mass. Are you trying to tell me that a 25% decrease in mass results in 44% increase in sustained turning performance??? There is something not accounted for here mate, something that Ps alone can not quantify. That’s where the lift coefficients and induced drag come to play. At the lower edge of the envelope. For the F-14 that’s between mach 0.2 and mach 0.7.
You already know the higher wing aspect gives the F-14 decrease in induced drag twice as large compared to the F-15. The NACA 64A209.65 mod 64A208.91 mod airfoil has a similar lift coefficient at the tip to the NACA 64A006.6 NACA 64A203 (used on the F-15), but unlike the F-15 which provides no effective lift at the root, the F-14’s has lift coefficient of 0.2. Add the 40% increase in lift experienced when going from 16 to 25 deg AoA a as a result of the body-glove vortex flow lift…… Do you need more evidence?As for what did i modify on my test chart, well it was an F-4E STR chart which i tweaked with the F-14A Ps curve and added the 20% increase in STR (of the F-14 VS F-4E) as documented by NASA. It still doesn’t tell the whole picture as the F-14 and the F-4 have very different aerodynamic properties especially on the left side of the diagram.
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The sample is not huge but IMHO is very interesting. IT suggests that the king of fighters in '80s was not F-15A but F-15B. (If you do not need ECM.)
It is interesting in one more aspect. In the entire history of the F-15, more then half its aerial victories were achieved by the Israeli Air Force. AND they are the only guys i know that have actually made gun kills in A-A since the mass introduction of guided missiles. I actually admire those people. They are probably among (if not THE) most skilled pilots in the world. Which kind of backs up the theory that in the end it is the pilot skill that is the most decisive factor in most ACMs.
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Ps does not tell the whole story, but it looks like Mike Metcalf beat me to it. You’re also putting a lot of faith in a chart that tells you outright that the back portion in the negative Ps is wrong, the rest is “satisfactory” and still fails to account for higher sustained turns than the listed max 15.3 deg/sec at the listed weights and altitude, which you also don’t have…Yea, verily, this chart is 100% accurate! I must disagree.
Mike, I think your empty weight is a little high for an A model; think its gross weight (assuming trapped fuel, oil, pilot, RIO etc.) is in the vicinity of 42,000-42,500; the B and D are higher in the 43k range gross. Also, the Tomcat would be even more brilliant at such a low weight, as was demonstrated back in 1973 during the flyoff against a pre-production F-15. The Tomcat loaded a sustained 8.5g turn, entering at 350 KIAS (26.5 deg/sec at about 1300ft circle) and exiting at 400 KIAS (23 deg/sec expanding to to about a 1700 ft circle - methinks Dennis Romano was pulling for all he had but still managed to build speed). He took off with about 2k fuel in the jet, so assuming about a 41k empty weight for the a/c at that time, it would have weighed in at around 43-44k when it did that maneuver. So, that should give you a point of reference for a “light” Tomcat - this of course is only worth examination for airshows, since with only 2k fuel over a combat zone, you’d find yourself pretty screwed pretty fast.
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Now, as to why specific excess power isn’t the whole story and with a concrete example of the F-14A. It is documented in video materials and photography that during air shows the F-14A was constantly being able to do a full 360 at minimum turning radius of about 1000ft without losing air speed in about 20 second.
Yes, with minimal fuel. Can you guess how can look F-15’s or F-14 Ps values if you subtract ~10’000 lbs from their weight…? This means Ps values are 100% good for justificaltion you just need the diagram with different config… Why? Explanation comes below.
That is a circle the length of about 6300ft. The sustained turning rate in these examples is about 18deg/s. Doing a 6300ft circle in 20 seconds translates to about 315ft per second or about 185-190 nautical miles per hour (knots) air speed. Performing this at airshow means this is practically at sea level wish would mean a mach number of about 0.28. Now take a look at he Ps values around mach 0.3. Based on Ps alone, the F-14A should be able to pull no more then 10 or 11deg/s at best.
Let’s presume that the aircraft performing this aerobatics at airshows are probably running an extremely light configuration with only 10% internal fuel. The empty weight of an F-14 is 43,735 lbs. Maximum internal fuel capacity is 16,200 lb. If our chart describes a clean AC with a 100% fuel tank that would account for a 59935lbs Tomcat. The airshow Tomcat would be 45355lbs in comparison. 75-76% the total mass. Are you trying to tell me that a 25% decrease in mass results in 44% increase in sustained turning performance???
You forgot about the 10k feet alt difference… Check F-15 Ps diagram. In 5G turn the Ps difference for F-15C between 10k and SL is about 450 ft/sec. (450 vs 900). Just the alt difference provides such a big Ps, because of bigger thrust and more dense air. The -25% weight & -10k feet alt can supply likely what you state for F-14A. Only problem that provdies for F-15 too…
You linked about a speed-turn rate (altitude) diagram about F-15C with clean config, 37’000 lbs weight. If you load only about 3’000 lbs fuel, F-15 weight is about 31’500 lbs.
We have diagram only about 35’000 lbs weight but at M0.3 check the sustained turn rate. 17 deg. –-> With 4’000 lbs less, I bet F-15 is able to reach 18 deg/sec. Why? Check the turn rate improvment between 39’000 lbs and 35’000 lbs. (If you do not have the diagram, the STR value increase 14.5 to 17 deg to sec because of -4’000 lbs weight.) So, in short, F-14 is not superior. In some area of flight envelope can be almost the same, but these areas of envelope are not useful in many vs. many combat even in 1:1. At low speed your missile defeat capability is 0… Because of max. G of F-15/F-16 is 9G - during ODS 11G was put at least one of the Eagle - the ITR is also better for F-15 at high speed.
Any pilot should have a very strange logic, if tries follow and beat F-14 where they are close to each other. F-15& F-16 smiply outclimb the F-14 while can keep better or the same turn ratio at bigger speed… I have explained about the “path projection” of turn during climbing. Can you guess why both F-16 and F-15 was optimized close to M0.7-M0.9 and not for M0.3…?
Here is the diagram with 35’000 lbs weight.
There is something not accounted for here mate, something that Ps alone can not quantify. That’s where the lift coefficients and induced drag come to play.
Your long theory is pontless beause of the pure nature of Ps, it includes all the factors what you mentioned. This is why required 10k+ hour wind tunnel tests for F-15 during the FX because CL and CD values are required for supply Ps-envelope diagrams and testify the available Ps and capabilites of the conception, as the Development Concept Paper demanded.
F-15 was ordered from paper, was no flyoff, so only wind tunnel data was available and projected weight. Should I link some documents about EM-Ps theory? Because as I see, you never checked. This is why so wonderful any envelope diagram which is supplied with Ps values. And this is why so found so few, because they are mostly classified…
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Should I link some documents about EM-Ps theory? - -
Yes please. This is getting interesting.
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http://www.aviation.org.uk/docs/flighttest.navair.navy.milunrestricted-FTM108/c5.pdf
http://www.aviation.org.uk/docs/flighttest.navair.navy.milunrestricted-FTM108/c6.pdf
http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA320211
You can see lift and drag forces in equations, but without measured CL & CD data you cannot solve them… The method can be used vica versa, you can count the necessary CL and CD and thrust for certain goals and you can compare easily different AC in the same situation. Because thrust curves and many other characteristics curve which contains data you can compare even “virtual aircraft” with existing AC.
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EDITED
Bah you know what? Lets take the F-14 dogfighting disscussion off of here and over to general discussion. Too heated and off topic. Lets not distract from this awesome pit!