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Best turning rate fighter

Unread postPosted: 16 Jan 2012, 18:30
by calel
Is the F-16 the fighter with the best turn rate??? I mean, no one turns better than the Viper?

RE: Best turning rate fighter

Unread postPosted: 16 Jan 2012, 20:43
by hcobb
Not at 60k feet.

Re: RE: Best turning rate fighter

Unread postPosted: 16 Jan 2012, 21:12
by southernphantom
hcobb wrote:Not at 60k feet.


The Raptor is going to out-turn anything at that altitude, in all likelihood.

Funny thing: At high altitude, a B-52 can turn inside an F-15 :lol: :lol:

Re: RE: Best turning rate fighter

Unread postPosted: 16 Jan 2012, 22:29
by expedite
southernphantom wrote:
hcobb wrote:Not at 60k feet.


The Raptor is going to out-turn anything at that altitude, in all likelihood.

Funny thing: At high altitude, a B-52 can turn inside an F-15 :lol: :lol:


Whaaa? :shrug:

Re: RE: Best turning rate fighter

Unread postPosted: 16 Jan 2012, 22:51
by southernphantom
expedite wrote:
southernphantom wrote:
hcobb wrote:Not at 60k feet.


The Raptor is going to out-turn anything at that altitude, in all likelihood.

Funny thing: At high altitude, a B-52 can turn inside an F-15 :lol: :lol:


Whaaa? :shrug:


Just something I've heard. I don't remember where, so that either means it's totally off-base, or absolutely spot-on (I'm good friends with a few retired BUFF crewdogs).

RE: Re: RE: Best turning rate fighter

Unread postPosted: 16 Jan 2012, 22:53
by hcobb
That was the entire reason to build the B-36, which was carefully kept far far away from any MiGs so as to not test this and expose the USAF as a paper tiger.

Unread postPosted: 17 Jan 2012, 00:44
by Obi_Offiah
The Dassault Rafale has a better turn rate.

Unread postPosted: 17 Jan 2012, 19:41
by wrightwing
At what speed, altitude, weight, etc....? Sustained/Instantaneous? The Raptor, Typhoon, Rafale, and Gripen would all likely have better sustained and instantaneous turn rates, at most areas of the flight envelope. The Flanker and Fulcrum would also meet or exceed the Viper in certain areas of the envlope(especially at low speeds).

Unread postPosted: 17 Jan 2012, 22:39
by tacf-x
The F-16 has an outstanding roll rate but the the Raptor has it beat in instantaneous (due to TVC) and sustained turn rates especially at high altitudes where control surfaces aren't that effective in the low density atmosphere.

Unread postPosted: 18 Jan 2012, 07:16
by Obi_Offiah
tacf-x wrote:The F-16 has an outstanding roll rate but the the Raptor has it beat in instantaneous (due to TVC) and sustained turn rates especially at high altitudes where control surfaces aren't that effective in the low density atmosphere.


Hi tacf-x

I don't think its the Vipers roll rate that is outstanding, but its roll acceleration. Its maximum roll rate is around 220 degrees per second which is similar to that of the Hornet and Super Hornet (225 dps).

Unread postPosted: 18 Jan 2012, 15:23
by tacf-x
Sounds reasonable. The F-16 does look like it has a low moment of inertia about that axis so the differential deflection of ailerons will give quite a net angular acceleration.

Unread postPosted: 18 Jan 2012, 16:44
by johnwill
The standard in measuring roll performance is "time to bank". Time to bank means how long it takes an airplane to go from wings level to a specified bank angle, such as 180 deg or 360 deg. So both roll acceleration and roll rate are involved. In banking 180 deg, roll acceleration is more important, while roll rate is more important for the 360 roll.

As far as F-16 goes, the highest roll rate I observed in flight test was 240 deg/sec, but that was an unusual case. Obi is right that about 220 dps is the normal max rate. Max rate and max acceleration also varies greatly according to several factors, including mach number, altitude, and external store loading. For low altitude supersonic, max rate is about 180 dps. With fly by wire, roll performance can be tailored to whatever is desired, within the max capability of the airplane. One thing you may have noticed in F-16 airshows is how quickly the airplane stops a roll. Roll initiation acceleration is about 8 rad/sec2, but at termination it is about 12 rad/sec2. That is an example of how fly by wire can tailor the performance. The airplane could easily accelerate into a roll at 12 rad/sec2, but it would feel too "twitchy".

Unread postPosted: 18 Jan 2012, 17:39
by Meteor
As wrightwing stated, "it depends". You need to define the conditions; for example; 50% internal fuel load, 5000' MSL, standard temp day, clean configuration, instantaneous or sustained rate, etc. If you had the EM diagrams for each aircraft it would be an easy exercise. Since the information is classified, you can only make anecdotal comparisons on an open forum such as this one. For example, watching a few youtube videos should make it obvious that the SU-30 and F-22 have far superior turn rates than the F-16 during post stall maneuvering.

Unread postPosted: 18 Jan 2012, 23:19
by fatcap
So what's the difference between the max commanded roll rate of 324°/s and the actual 240°/s?
Cheers!

Unread postPosted: 19 Jan 2012, 05:12
by johnwill
I assume you are talking about the F-16 flight control laws which use the difference between a roll rate command and the actual roll rate feedback to command an aileron deflection to the flaperons and horizontal tail. If so, the 324 d/s max command results in a flaperon and tail deflection which can generate a 220 or 240 d/s roll rate. There are other ways to compute a deflection, but that is the way GD flight control engineers chose to do it. Remember, roll performance specs are "time to bank", so actual roll rate is irrelevant to spec compliance.