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F-14 low speed prowess vs Other Aircraft


Hummingbird

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Question is: Why are these charts only available publicly for certain aircraft like the F-16, -18 & -15, aircraft which are still in active service and serve as vital instruments to western air supremacy, yet no similar charts are available for the retired F-14?

 

Seems rather odd if you ask me.

 

In regards to the F-16 9 G min radius 360 turn, a turn radius of 1400 ft was achieved and it took 19 sec to complete.

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What?

 

http://forums.eagle.ru/showpost.php?p=2340360&postcount=98

 

Both are available. The A's been available for a good fifteen years online. The B/D had a high price of admission, being the far fewer number copies of that book generated over the years. As it currently stands, you're talking to the only person distributing the latter short of finding your own hardcopy.

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What?

 

http://forums.eagle.ru/showpost.php?p=2340360&postcount=98

 

Both are available. The A's been available for a good fifteen years online. The B/D had a high price of admission, being the far fewer number copies of that book generated over the years. As it currently stands, you're talking to the only person distributing the latter short of finding your own hardcopy.

 

Many thanks for providing these lunaticfringe, I only wish I could open them :(

 

EDIT: Managed to open them, they just took a while to load that's all. Excellent stuff, will be useful to the devs for sure :)


Edited by Hummingbird
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It takes a bit for the jpgs to load. If it doesn't work, holler.

 

And note: those pages were provided as a challenge to someone (for them to present their own data on the MiG-23)- the B/D pages are with "Maneuvering Devices NOT Operating", ergo, no auto flaps/slats, which is to say a margin less than it'll really do.

 

Basically trying to show that you could gimp an F-14 and still not get a Flogger to take it.

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It takes a bit for the jpgs to load. If it doesn't work, holler.

 

And note: those pages were provided as a challenge to someone (for them to present their own data on the MiG-23)- the B/D pages are with "Maneuvering Devices NOT Operating", ergo, no auto flaps/slats, which is to say a margin less than it'll really do.

 

Basically trying to show that you could gimp an F-14 and still not get a Flogger to take it.

 

What about compared to the F-15C then? How do the two compare clean in sustained maneuvers ? (with the F-14 using its slats & auto flaps ofcourse)

 

Btw, regarding the 6.5 G load limit for the F-14, how far away was this from the actual ultimate load of the airframe in comparison to the F-15?

 

Apologies for the questions, but it's not everyday you meet an F-14 expert :)

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Messages 58-67 in this thread pretty much cover your first question.

 

With respects to the G limitation, the F-14's original sweep program was for CL max. The Navy didn't like the amount of flexing moment they witnessed in the wing, and had Grumman reprogram the system for Ps.

 

This gets into the G limitation for the reason that the test flight aircrews were told to treat it like a 13G airframe and fly it accordingly. Military aircraft are generally designed for stresses up to 1.5 times operational G limit (although there are exceptions: see F-16, having a substantially lower margin).

 

If 13G was the point Grumman was telling their pilots how to treat it- and you can be certain that the flight test aircraft were abused to make sure the state of the art construction/fabrication techniques used in the type, you're realistically looking at a design target of 8.5-9G.

 

As others have said elsewhere, it was the reality of the 70's economy that made the Navy begin worrying about long term purchases; some of this involved the nature of the flyaway price lockdown that Grumman offered to the Navy, which blew up in their face with the energy crisis. Had clearance not been given for the sale of the Tomcat to Iran, if memory serves, Grumman would have been forced to close its doors in 1977 because the prices were not permitted to change over the first few Blocks.

 

When you're up against that sort of situation, you're going to baby your favorite toys, because you may never get any more of them, and you're a long way away from being able to get a suitable replacement.

 

The flipside of this what was done to the machine in service. Hoser put 10+G on one avoiding Hawk Monroe, and did even worse at AIM/ACE. Muczynski put 10.2 on Fast Eagle 107, and there wasn't a single issue during the required inspection. A good pal of mine, former RIO, had his pilot put 9.5 on in a break turn during a FFARP setup, and nothing was found in the way of stress or damage- this was 1989 at this point, and was in an A from what would have been the 82/83 timeframe (if memory serves), and they'd all been pushed pretty good by this point during multiple excursions over the op limit.

 

Some of the electronics hated the stress that would be put on them, which caused many of the changes over the years in replacement versions of the boxes, but the machine itself was a beast. I know a lot of ex-crews, and I am hard pressed to find any of them who have recollection of overstress doing anything substantial.

 

Fun fact, while we're at it (that RIO pal with the 9G introduction of his face to his kneecap would be mad if I didn't tell somebody): part of the Tomcat went to the Moon.

 

Take a guess which.


Edited by lunaticfringe
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Excellent info Lunaticfringe :)

 

And apologies for speaking past you earlier (you too GG), but I think part of it could be that english isn't my first language, thus definitions sometimes get mixed up :)

 

As for the moon part, well if it wasn't the RIO himself then I can't guess it :D

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The detonation cord used to ignite the explosive bolts separating the ascent stage from the decent state of the LM was used for the same purpose on the F-14's canopy. Only difference was the length.

 

Pretty interesting, when you think about the fact that the LM was the only component not to fail during the program (and went far beyond its design specification during Apollo 13).

 

Too bad it didn't work for Goose. ;)

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Messages 58-67 in this thread pretty much cover your first question.

 

With respects to the G limitation, the F-14's original sweep program was for CL max. The Navy didn't like the amount of flexing moment they witnessed in the wing, and had Grumman reprogram the system for Ps.

 

This gets into the G limitation for the reason that the test flight aircrews were told to treat it like a 13G airframe and fly it accordingly. Military aircraft are generally designed for stresses up to 1.5 times operational G limit (although there are exceptions: see F-16, having a substantially lower margin).

 

If 13G was the point Grumman was telling their pilots how to treat it- and you can be certain that the flight test aircraft were abused to make sure the state of the art construction/fabrication techniques used in the type, you're realistically looking at a design target of 8.5-9G.

 

As others have said elsewhere, it was the reality of the 70's economy that made the Navy begin worrying about long term purchases; some of this involved the nature of the flyaway price lockdown that Grumman offered to the Navy, which blew up in their face with the energy crisis. Had clearance not been given for the sale of the Tomcat to Iran, if memory serves, Grumman would have been forced to close its doors in 1977 because the prices were not permitted to change over the first few Blocks.

 

When you're up against that sort of situation, you're going to baby your favorite toys, because you may never get any more of them, and you're a long way away from being able to get a suitable replacement.

 

The flipside of this what was done to the machine in service. Hoser put 10+G on one avoiding Hawk Monroe, and did even worse at AIM/ACE. Muczynski put 10.2 on Fast Eagle 107, and there wasn't a single issue during the required inspection. A good pal of mine, former RIO, had his pilot put 9.5 on in a break turn during a FFARP setup, and nothing was found in the way of stress or damage- this was 1989 at this point, and was in an A from what would have been the 82/83 timeframe (if memory serves), and they'd all been pushed pretty good by this point during multiple excursions over the op limit.

 

Some of the electronics hated the stress that would be put on them, which caused many of the changes over the years in replacement versions of the boxes, but the machine itself was a beast. I know a lot of ex-crews, and I am hard pressed to find any of them who have recollection of overstress doing anything substantial.

 

Fun fact, while we're at it (that RIO pal with the 9G introduction of his face to his kneecap would be mad if I didn't tell somebody): part of the Tomcat went to the Moon.

 

Take a guess which.

 

I've only got fleet stories-akin to fishing stories, but one story, only one I've heard came from an AE on a mid 90s cruise who said that an F-18 driver bet he could outurn an F-14, so they settled it in the air, behind the carrier.( no idea to the credibility, as the Skipper and CAG would have fried if anything happened) but they entered a turn aft of the carrier at co-speed with altitude separation. You can expect the F-18 used his pinky paddle to allow a tighter turn, and the F-14 driver pulled for all he could. The F-14 pulled a tighter turn to 180 degrees but, said AE witnessed several panels fly off the F-14. When the jets landed they were both inspected and the F-14 was craned off after the cruise finished. Other than that, after talking to many F-14 crews and maintainers, I've never heard a single instance of an overstress incurring more than the extra maintenance time to do a full inspection.

One particular note is an LM F-35 rep at Andrews AFB Open House in 2003, stated that the F-14s best turn in dogfighting really was 6.5g for rate, radius, and energy sustainment. Putting 8g on it didn't get you that many more degrees and nobody pulls a turn like that for 360 degrees in a dogfight. So, airshow degrees and seconds aside, instantaneous is what really matters, with sustained rate primarily being a indicator of energy management.

I missed a lot of this discussion, but it's becoming a pointless F-15 vs F-14 thread(internet trolls rejoice).

VF-2 Bounty Hunters

 

https://www.csg-1.com/

DCS F-14 Pilot/RIO Discord:

https://discord.gg/6bbthxk

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AE's gonna know the pilot's name for that kind of stunt, because it's going to make the rounds over the entire air wing, if not the carrier group. *Everybody* watching that and seeing panels come off is going to want the name of the guy(s) who just got promoted off ship. Did he mention one?

 

And the F-15/F-14 thing was just fine. Turned into an F-15 vs A6M fight for a bit. Now we're all just shootin' the breeze.

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Fun fact, while we're at it (that RIO pal with the 9G introduction of his face to his kneecap would be mad if I didn't tell somebody): part of the Tomcat went to the Moon.

 

 

Did this RIO happen to be looking for a switch when his pilot suddenly made a hard break (spotting an A-4 or something all of a sudden)? :smilewink: :music_whistling:

 

 

And the F-15/F-14 thing was just fine. Turned into an F-15 vs A6M fight for a bit. Now we're all just shootin' the breeze.

 

Ah, there is still that last chart to be uploaded, but it will have to wait until later today :)

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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Did this RIO happen to be looking for a switch when his pilot suddenly made a hard break (spotting an A-4 or something all of a sudden)? :smilewink: :music_whistling:

 

He put the tale in a blog post a number of years before I finally got to hoist a few beers with him in person. Good people, and it's always fun chatting with him privately.

 

He's got a connection to a famous F-14 incident that's worth buying a round if you can get him in the right circumstances- it's his story to tell, though, and I don't do it justice.

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He put the tale in a blog post a number of years before I finally got to hoist a few beers with him in person. Good people, and it's always fun chatting with him privately.

 

He's got a connection to a famous F-14 incident that's worth buying a round if you can get him in the right circumstances- it's his story to tell, though, and I don't do it justice.

 

Personally it's one of my favorite F-14 anecdotes of all time. The next time you meat the man, you can offer him my regards and respect :thumbup:

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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Here are those F-14B F-15C overlays finally. Altitude is 10000ft, the loads are as previous, 4 Sparrows, 4 Sidewinders. As expected they do seam to close in on each other, but the greatest change when compared to the F-14A is what you actually don't see from the chart. The excess energy and the climb rate being the most apparent.

 

This is the chart with the PW-100 powered Eagle:

 

wgHWbgm.jpg

And this is the chart with the PW-220 powered Eagle:

 

bfYWzAE.jpg

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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You absolutely have no idea what you're talking about to make such a patently false statement, and this is explicitly the reason why I've been stating that USAF manuals are deficient in providing the Ps compared to the doghouse. We're not discussing *sustained turns*: we're discussing a turn in which induced drag will pull the aircraft through CV- right at the top of the plot.

 

Fine, start at Mach .8/3000' radius. By the time you're complete at Mach .5 (or thereabouts), your actual radius will be below 2500'. And that's at 15k; bring it down to SL, and you're talking sub-2000' radii with a turn rate in excess of 20+ dps.

 

Nah, F-15 can't do that.

 

I used this 15k chart as a basis for my following iteration. Looking at the Ps=0 curve, i tried to find the closest match in the F-15 dash one's. Turns out it is fairly close to what would be 15000ft estimated sustained turn performance for a PW-100 powered F-15. Not an exact match really, especially not in the low mach region, but close enough to make it interesting and worthy for a rough comparison:

 

ku7CXfU.jpg

The red line is my estimation of the 15kft Ps=0 for the 4+4 F-15A/C, and the blue lines are taken from your post. If we overlay these with the F-14A at 15000ft, we should get something similar to this:

 

cTq5gBV.jpg

 

Note that the F-14A max lift curve goes only up to 7g, because it taken verbatim from the manual. We can compute it up to 9g if needed though.

 

EDIT: sorry for the double post, but i had to re upload the last two graphs, as my PC went down during a power outage.

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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Are those charts with the F-14 using its slats/flaps?

 

Yes.

Modules: FC3, Mirage 2000C, Harrier AV-8B NA, F-5, AJS-37 Viggen, F-14B, F-14A, Combined Arms, F/A-18C, F-16C, MiG-19P, F-86, MiG-15, FW-190A, Spitfire Mk IX, UH-1 Huey, Su-25, P-51PD, Caucasus map, Nevada map, Persian Gulf map, Marianas map, Syria Map, Super Carrier, Sinai map, Mosquito, P-51, AH-64 Apache

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Yes.

 

There's something I don't understand then, which is: According to your chart the F-15 features a higher STR below ~200 kts, which to me is odd considering the lower effective wing loading of the F-14.

 

According to Lunaticfringe the F-14 holds an average 1 G advantage below M 0.75 & 15k ft over the F-15 in STR.

 

i.e. the F-14 ought to be able to keep turning at a lower speed than the F-15, and thus the lower STR below 200 kts on your chart makes no sense to me.

 

Don't know how the chart would look with the F-14B/D with its extra thrust.

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There's something I don't understand then, which is: According to your chart the F-15 features a higher STR below ~200 kts, which to me is odd considering the lower effective wing loading of the F-14.

 

It isn't odd at all, nor is the cat's wing loading necessarily lower.

 

According to Lunaticfringe the F-14 holds an average 1 G advantage below M 0.75 & 15k ft over the F-15 in STR.
Except it very clearly does not. Reading charts is still better than quoting a number - I thought we had just gone over this :)

No one is immune to making a statement that isn't entirely correct. I was misreading charts all day long when the real comparisons had just started.

 

i.e. the F-14 ought to be able to keep turning at a lower speed than the F-15, and thus the lower STR below 200 kts on your chart makes no sense to me.
No, this is factual - so it makes all the sense in the world. It's just how things are. What doesn't make sense is what you did above - quote a number and use it to ignore a huge part of the flight envelope.

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I used to play flight sims like you, but then I took a slammer to the knee - Yoda

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It isn't odd at all, nor is the cat's wing loading necessarily lower.

 

According to everything I've read the F-14's effective wing loading is definitely lower (remember it features a substantially lower stall speed), and Dalan's instantanous turn chart seems to support this, with the F-14 holding an average advantage of 2 dps across the board.

 

His sustained turn chart just doesn't make much sense after though.

 

Except it very clearly does not. Reading charts is still better than quoting a number - I thought we had just gone over this :)

No one is immune to making a statement that isn't entirely correct. I was misreading charts all day long when the real comparisons had just started.

 

Lunaticfringe holds the relevant charts, so why am I not to trust him?

 

No, this is factual - so it makes all the sense in the world. It's just how things are. What doesn't make sense is what you did above - quote a number and use it to ignore a huge part of the flight envelope.

 

Not going to argue with you mate, I'm only interested in the facts and so far it seems rather clear to me that the F-14 hold the advantage in ITR & STR below mach 0.7, which makes perfect sense.

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According to everything I've read the F-14's effective wing loading is definitely lower (remember it features a substantially lower stall speed), and Dalan's instantanous turn chart seems to support this, with the F-14 holding an average advantage of 2 dps across the board.

 

... except it doesn't for STR. Chart reading 101, again. And I suggest doing your own math instead of 'everything I've read'. You might be surprised at how much sense 'everything I read' doesn't make :)

 

His sustained turn chart just doesn't make much sense after though.
It's not 'his' chart, it's the USN's and USAF's charts created by flying the aircraft.

 

Lunaticfringe holds the relevant charts, so why am I not to trust him?
Did you miss the part where we were comparing charts?

 

Not going to argue with you mate, I'm only interested in the facts and so far it seems rather clear to me that the F-14 hold the advantage in ITR & STR below mach 0.7, which makes perfect sense.
Until you drop below mach 0.35. The facts are on the chart. What's the problem?
Edited by GGTharos

[sIGPIC][/sIGPIC]

Reminder: SAM = Speed Bump :D

I used to play flight sims like you, but then I took a slammer to the knee - Yoda

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... except it doesn't for STR. Chart reading 101, again. And I suggest doing your own math instead of 'everything I've read'. You might be surprised at how much sense 'everything I read' doesn't make :)

 

Haha, I see this Tharos however it is exactly that part which doesn't make sense to me :D

 

Clearly the F-14 hold an advantage in lift to weight ratio, otherwise its' stall speed wouldn't be so much lower and its' ITR so much higher across the board. What SHOULD also then hold true would be that it's STR ought to be better all the way to Mach 0.75, after which point the F-15 takes over.

 

It's not 'his' chart, it's the USN's and USAF's charts created by flying the aircraft.

 

Did you miss the part where we were comparing charts?

 

Didn't Lunaticfringe note that you were reading the wrong charts?

 

Until you drop below mach 0.35. The facts are on the chart. What's the problem?

 

My problem is that I don't have the F-14 charts :D

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Haha, I see this Tharos however it is exactly that part which doesn't make sense to me :D

 

Clearly the F-14 hold an advantage in lift to weight ratio, otherwise its' stall speed wouldn't be so much lower and its' ITR so much higher across the board. What SHOULD also then hold true would be that it's STR ought to be better all the way to Mach 0.75, after which point the F-15 takes over.

 

Right, let's make sense of it.

First off, the wing loading is irrelevant. Why? Because all by itself it means nothing. Put it this way:

 

What's the wing loading of a glider?

What is its STR?

Why is it lower than that of an A6M? :D

Whos stalls first? Glider or A6M? Why?

 

In case it's still unlear: Thrust (more specifically TWR, but TWR is affected by thrust) is the other component that allows you to maintain an STR.

All engines and inlets are not created equal, and jet engines do not provide constant thrust throughout the airspeed envelope.

 

It looks like the cat's engines lose a lot of thrust below M0.35 compared to the eagle.

 

Arguably that might be a useless part of the envelope.

 

Didn't Lunaticfringe note that you were reading the wrong charts?

 

We noted that I was tired and going back and forth between charts. In the end I chose the wrong one, but the result remains that the two aircraft turn at similar STRs at their respective regimes.

 

My problem is that I don't have the F-14 charts :D

 

You have charts posted here in this thread.

[sIGPIC][/sIGPIC]

Reminder: SAM = Speed Bump :D

I used to play flight sims like you, but then I took a slammer to the knee - Yoda

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Right, let's make sense of it.

First off, the wing loading is irrelevant. Why? Because all by itself it means nothing. Put it this way:

 

What's the wing loading of a glider?

What is its STR?

Why is it lower than that of an A6M? :D

Whos stalls first? Glider or A6M? Why?

 

 

In case it's still unlear: Thrust (more specifically TWR, but TWR is affected by thrust) is the other component that allows you to maintain an STR.

 

All of this is clear to me, it is the change from higher to lower STR in comparison to the F-15 at mach ~0.35 that is confusing me (albeit the explanation could be what you mention in the quote below)

 

You disagreeing about the F-14's lower effective wing loading mystifies me though as it is clearly lower, proven via the F-14's higher ITR and substantially lower stall speed.

 

All engines and inlets are not created equal, and jet engines do not provide constant thrust throughout the airspeed envelope.

 

It looks like the cat's engines lose a lot of thrust below M0.35 compared to the eagle.

 

See now THAT's what I'm talking about! I can use this to make at least some sense of it now, seeing as I never really considered this :)

 

You see I was comparing the two considering a similar curve in available thrust.

 

Arguably that might be a useless part of the envelope.

 

Maybe, I'm not sure.

 

We noted that I was tired and going back and forth between charts. In the end I chose the wrong one, but the result remains that the two aircraft turn at similar STRs at their respective regimes.

 

The F-14B/D seems to hold a slight advantage in max STR, and significant one in ITR though. (According to Dalan's charts at least)

 

You have charts posted here in this thread.

 

I don't have the original STR charts for the F-14's, only a comparisons overlay which I cannot check the accuracy of :)


Edited by Hummingbird
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