F-14 low speed prowess vs Other Aircraft

[captain_dalan]

Probably a lack of engine thrust at that altitude. Do you have it's sustained G performance for 10,000 ft?

Yeah, the data i have is some of the more detailed i have acquired so far, it goes from SL to 45000ft in 5000ft increments, but it would take some time to scan them all. The thing that puzzles me the most how the AC performance seams to "skip a bit" at some altitudes. If not an error, then engine and aerodynamic performance must be much more subtle variables then i originally though.

 

I am also trying to do an overlay of the Su-27 (i found an online version of the export flight manual) and there are some neat max Inst and Sust G available graphs there for a 2+2 AAMs 50% fuel load.

[Hummingbird]

Yeah, the data i have is some of the more detailed i have acquired so far, it goes from SL to 45000ft in 5000ft increments, but it would take some time to scan them all. The thing that puzzles me the most how the AC performance seams to "skip a bit" at some altitudes. If not an error, then engine and aerodynamic performance must be much more subtle variables then i originally though.

 

I am also trying to do an overlay of the Su-27 (i found an online version of the export flight manual) and there are some neat max Inst and Sust G available graphs there for a 2+2 AAMs 50% fuel load.

 

It's probably a combination of engine performance characteristics and the high amount of parasitic drag experienced by the F-18 in certain situations.

 

That having been said the charts point toward the F-18 enjoying a lift to weight advantage over the F-15, which isn't surprising considering the extensive use of strakes and high lift devices, however the parasitic drag is obviously hurting it though as we can see when looking at its' limited performance in sustained maneuvering - not to mention it's problems crossing Mach 2 at higher alts.

 

Low alt is where the F-18 naturally wants to be, up high it seems to suffer a lot.

[Hummingbird]

I wonder how accurate this is:

 

If so the F-18C comes pretty damn close to the F-18E even with wing tanks, which is quite impressive.

Edited May 1, 2015 by Hummingbird

[Hummingbird]

The pitch rate of the F-18 is certainly impressive, not sure any other fighter can match it here:

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[SilentGun]

 

Has anyone else noticed that the model tomcat is an A in this vid? Wonder what an B or a D could do. (don't know if it was said already but I don't want to search through several pages tot find out.)

[Hummingbird]

Has anyone else noticed that the model tomcat is an A in this vid? Wonder what an B or a D could do. (don't know if it was said already but I don't want to search through several pages tot find out.)

 

Well the A+/B or D would do even better due to the significant increase in thrust provided by the more powerful F110-GE-400 engines. The sustained G performance was improved by about 0.1-0.2 G's at most speeds, as you can see below:

 

Sustained G performance of the F-14A & D, F-16C & F-15C in comparison at 10,000 ft

 

F-14D @ 55,620 lbs (50% fuel) w/ 4x AIM-7's + 4x AIM-9's @ 10,000 ft:

Mach = G-load

0.2 = 1.2

0.3 = 1.95

0.4 = 2.95

0.5 = 4.0

0.6 = 5.0

0.7 = 5.3

0.75 = 5.6

 

F-14A @ 53,873 lbs (50% fuel) w/ 4x AIM-7's + 4x AIM-9's @ 10,000 ft:

Mach = G-load

0.2 = 1.1

0.3 = 1.8

0.4 = 2.8

0.5 = 3.9

0.6 = 4.9

0.7 = 5.2

0.75 = 5.5

 

F-16C @ 26,000 lbs w/ 2x AIM-9 + 4x AIM-120's + 2x FT pylons @ 10,000 ft:

Mach = G-load

0.2 = CAT limited

0.3 = 1.8

0.4 = 2.7

0.5 = 3.55

0.6 = 4.5

0.7 = 5.5

0.75 = 6.0

 

F-15C @ 41,000 lbs (50% fuel), w/ 4x AIM-7's + 4x AIM-9s @ 10,000 ft:

Mach = G-load

0.2 = 1.0

0.3 = 1.8

0.4 = 2.6

0.5 = 3.4

0.6 = 4.3

0.7 = 5.25

0.75 = 5.7

 

Once again all the figures are from the aircraft's respective manuals.

[BlackLion213]

Has anyone else noticed that the model tomcat is an A in this vid? Wonder what an B or a D could do. (don't know if it was said already but I don't want to search through several pages tot find out.)

 

I remember speaking to a VF-213 pilot in 1997 at the Dayton Airshow. They had just finished transitioning from the F-14A to the F-14D (donated by VF-11 :)). I asked him if he noticed a big difference in maneuverability and surprisingly, he said no. He thought the F-14D was a huge upgrade and loved the new F110s, they allowed much better sustained vertical maneuvers and better acceleration. Sustained turns seemed the same, except that the F-14A needed to trade altitude to sustain cornering speed above 10,000 ft (it maintained airspeed at min radius pretty well below ~5-7K feet). In the F-14D, you could climb a tiny bit and still maintain corner speeds at half internal fuel or less.

 

I bet that maneuver would look pretty similar between the two given the TF30s solid low altitude performance, except the ground would shake a lot more with the F-14D. The F110 powered Tomcats were hugely impressive at Airshow performances, the loudest/most visceral performer I have ever seen...well the B-1B is louder, but just a little ;)

 

-Nick

[Hummingbird]

Looking at the airshow video above (which is the hottest F-18 demo I've seen I must say) it seems that the F-18 takes about 2 sec longer to complete a 360 turn than the F-14 & F-16, but the first 150-160 deg are completed very fast, faster than most other fighters I've seen infact. The instantanuous pitch rate and high alpha capability of the F-18 truly is amazing! It pays a high prize in drag though, with the turn rate slowing down greatly past the first ~160 deg as a result.

 

The F-18 is still faster round a 360 than any F-15 demo I've seen though, but then again the F-15 first begins to shine at speeds above what we usually see at airshows.

Edited May 2, 2015 by Hummingbird

[GGTharos]

 

2:30

[BlackLion213]

 

2:30

 

Hmm...still not clear to me, but I think you're an F-15 fan. ;)

 

-Nick

[GGTharos]

It's pretty clear. Wings roll in at 2:33, roll out at 2:53. If you include the roll speed and the fact that F-15 pilots (or most real pilots, really), tend to make single-axis inputs, that F-15 is displaying a turn rate of more than 18deg/s. But now that's spitting hairs.

 

Or was it that you actually wanted more hair splitting? ;)

Edited May 2, 2015 by GGTharos

[BlackLion213]

Or was it that you actually wanted more hair splitting? ;)

 

I think that is all that these threads are about. The numbers are interesting, but how the pilot stitches these performance traits together is still more important than the numbers themselves, IMHO.

 

To me that was always the real training power of the F-5E - it reminds the pilots of 4th+ generation aircraft that they can still be shot down by something that doesn't measure up on any of these charts.

 

Still, interesting to see the differences and it emphasizes the strengths/weaknesses of each airframe.

 

-Nick

[Hummingbird]

 

2:30

 

A clean F-15 should be capable of it, but the F-14 & F-16 will be able to do it sooner & quicker, and I'd imagine the F-18C can come close, but we'll need the data that Dalan has available to see wether that's the case.

 

In airshow like configuration (2x AIM-9's) the F-16C is capable of a sustained 21.8 deg/sec @ SL, which is mighty impressive. The F-14B/D clean should be capable of a sustained 21.3 deg/sec @ SL, where'as the F-15C clean should be capable of a sustained 20.5 deg/sec @ SL.

 

In other words the F-16 is the king of sustained maneuvers in the clean or near clean configuration.

 

As for the F-18, I'm suspecting around 18.5-19 deg/sec sustained at SL, however it will undoubtedly trumpf the rest in instantanuous pitch rate though, which is a rather crucial advantage in a dogfight.

[Exorcet]

I think that is all that these threads are about. The numbers are interesting, but how the pilot stitches these performance traits together is still more important than the numbers themselves, IMHO.

 

Personally I'd like to know exactly why each plane is capable of what it is. While I can see why one could argue that the F-14 is aerodynamically superior to the F-15 and F-16, what surprises me is that it apparently overcomes the drastic weight difference. I really wish I had surface pressure plots for each aircraft.

[BlackLion213]

A clean F-15 should be capable of it, but the F-14 & F-16 will be able to do it sooner & quicker, and I'd imagine the F-18C can come close, but we'll need the data that Dalan has available to see wether that's the case.

 

In airshow like configuration (2x AIM-9's) the F-16C is capable of a sustained 21.8 deg/sec @ SL, which is mighty impressive. The F-14B/D clean should be capable of a sustained 21.3 deg/sec @ SL, where'as the F-15C clean should be capable of a sustained 20.5 deg/sec @ SL.

 

In other words the F-16 is the king of sustained maneuvers in the clean or near clean configuration.

 

As for the F-18, I'm suspecting around 18.5-19 deg/sec sustained at SL, however it will undoubtedly trumpf the rest in instantanuous pitch rate though, which is a rather crucial advantage in a dogfight.

 

The striking part about those numbers is how similar they are despite the big differences in weight and wing configuration. The Tomcat, Flanker, and Raptor, which are all 40-45K lbs empty, have certainly established that mass does not preclude an impressive STR.

 

-Nick

[GGTharos]

You said you've never seen an F-15 doing that in a show, and that was a direct answer to that.

 

I didn't realize you just wanted to read more charts. :)

Since you did though ... a combat-loaded F-15 will do that particular turn, too.

 

A clean F-15 should be capable of it, but the F-14 & F-16 will be able to do it sooner & quicker, and I'd imagine the F-18C can come close, but we'll need the data that Dalan has available to see wether that's the case.

 

In airshow like configuration (2x AIM-9's) the F-16C is capable of a sustained 21.8 deg/sec @ SL, which is mighty impressive. The F-14B/D clean should be capable of a sustained 21.3 deg/sec @ SL, where'as the F-15C clean should be capable of a sustained 20.5 deg/sec @ SL.

 

In other words the F-16 is the king of sustained maneuvers in the clean or near clean configuration.

 

As for the F-18, I'm suspecting around 18.5-19 deg/sec sustained at SL, however it will undoubtedly trumpf the rest in instantanuous pitch rate though, which is a rather crucial advantage in a dogfight.

Edited May 3, 2015 by GGTharos

[SDsc0rch]

kickass vid!

[Hummingbird]

You said you've never seen an F-15 doing that in a show, and that was a direct answer to that.

 

I indeed hadn't. At all the airshows I've seen the F-15 has always taken about 23 seconds or more to complete its min radius turns. But the most likely explanation for this is also rather simple in that the pilot in the video you just posted probably was going quite abit faster than usual to gain those extra deg/sec, at the expense of having to endure more G's pr. deg/sec obviously.

 

That's the thing with the F-15, it's best turn rates are at a rather high airspeed, around Mach 0.8-0.9 (depending on alt), and as such the pilot has to endure more G's to achieve the same rates than in for example the F-14 or F-16. Also as you probably know the speeds at most airshow demos rarely exceed Mach 0.7 (with an absolute max limit of 0.9 strictly for straight and level flight) and usually hover around Mach 0.5, and at such speeds the F-15 simply isn't as quick to complete it's maneuvers in comparison to the F-14 & F-16.

 

I didn't realize you just wanted to read more charts. :)

Since you did though ...

 

I don't quite follow? I asked Dalan for a chart on the F-18 before you came in :huh:

 

a combat-loaded F-15 will do that particular turn, too.

 

If the entry speed is high enough, sure. It won't be able to keep it up though.

[Hummingbird]

The striking part about those numbers is how similar they are despite the big differences in weight and wing configuration. The Tomcat, Flanker, and Raptor, which are all 40-45K lbs empty, have certainly established that mass does not preclude an impressive STR.

 

-Nick

 

Indeed, proper aerodynamics can make up for a lot of weight :)

 

Also now that you mentioned the Flanker, what's interesting is that the Russians not only copied the F-14's lifting body design with the wide funnel and airfoil shaped fuselage for their MiG-29 & Su-27 designs, but they've stuck with it ever since, even incorperating it into their new PAK FA. They simply couldn't ignore that huge amount of extra lift generated for a relative small penalty in drag.

[GGTharos]

I indeed hadn't. At all the airshows I've seen the F-15 has always taken about 23 seconds or more to complete its min radius turns. But the most likely explanation for this is also rather simple in that the pilot in the video you just posted probably was going quite abit faster than usual to gain those extra deg/sec, at the expense of having to endure more G's pr. deg/sec obviously.

 

18dps is achieved consistently under 400kts in just about any airshow configuration.

 

That's the thing with the F-15, it's best turn rates are at a rather high airspeed, around Mach 0.8-0.9 (depending on alt), and as such the pilot has to endure more G's to achieve the same rates than in for example the F-14 or F-16. Also as you probably know the speeds at most airshow demos rarely exceed Mach 0.7 (with an absolute max limit of 0.9 strictly for straight and level flight) and usually hover around Mach 0.5, and at such speeds the F-15 simply isn't as quick to complete it's maneuvers in comparison to the F-14 & F-16.

 

18DPS is achieved at ~0.6M in the heavy (38000lbs) airshow configuration.

A 20 second turn is 18DPS, and it would be performed at around 7g or less at that speed.

[BlackLion213]

Also now that you mentioned the Flanker, what's interesting is that the Russians not only copied the F-14's lifting body design with the wide funnel and airfoil shaped fuselage for their MiG-29 & Su-27 designs, but they've stuck with it ever since, even incorperating it into their new PAK FA. They simply couldn't ignore that huge amount of extra lift generated for a relative small penalty in drag.

 

Seems like solid reasoning to me. :)

 

-Nick

[Hummingbird]

18dps is achieved consistently under 400kts in just about any airshow configuration.

 

Yet again I've very rarely seen the F-15 do it, even in videos. But once more the speed at airshows is usually pretty low, hovering around mach 0.5 a lot, and the F-15 needs to go faster than that, so that probably partially explains it.

 

18DPS is achieved at ~0.6M in the heavy (38000lbs) airshow configuration.

A 20 second turn is 18DPS, and it would be performed at around 7g or less at that speed.

 

7 G's yes, which makes you understand why it probably isn't carried out all the time.

[Basher54321]

I think that is all that these threads are about. The numbers are interesting, but how the pilot stitches these performance traits together is still more important than the numbers themselves, IMHO.

 

To me that was always the real training power of the F-5E - it reminds the pilots of 4th+ generation aircraft that they can still be shot down by something that doesn't measure up on any of these charts.

 

 

-Nick

 

Spot on - it's the whole package that is important!

[GGTharos]

Yet again I've very rarely seen the F-15 do it, even in videos. But once more the speed at airshows is usually pretty low, hovering around mach 0.5 a lot, and the F-15 needs to go faster than that, so that probably partially explains it.

 

That's just making stuff up. Maneuver speeds are set in writing in the demo AFIs, and I believe the most recent one is AFI11-246:

 

Airspeed and G Limits.

Demonstration pilots will not exceed 0.94 Mach. The maximum

target G for this demonstration is 7.5 Gs. This does not preclude a momentary increase in G for

safety considerations.

 

 

You fly the maneuver speed, and they're pretty much all over the place, as required so long as they are subsonic.

 

7 G's yes, which makes you understand why it probably isn't carried out all the time.

No, it doesn't. 7G is pretty much par for the course for eagle pilots. They're not the only ones who sustain high g-loads in demos either.
Edited May 4, 2015 by GGTharos

[Hummingbird]

That's just making stuff up. Maneuver speeds are set in writing in the demo AFIs, and I believe the most recent one is AFI11-246:

 

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You fly the maneuver speed, and they're pretty much all over the place, as required so long as they are subsonic.

 

No, it doesn't. 7G is pretty much par for the course for eagle pilots. They're not the only ones who sustain high g-loads in demos either.

 

Oh would you quit it already GGTharos! You really are the most passive aggressive person I've ever met, and you're a moderator too!

 

No'one is making anything up, but it's obvious you get butthurt over any little phrase that doesn't praise the F-15 to the sun.

 

Fact is that I've rarely seen F-15's do such turns, and that's most likely because they've been going slower than Mach 0.6. That's it, deal with it.