Acft Turn Rate

[Felix58]

Plucked the following from an old flight sim website re turn rate in kmh.

Vc = Velocity Climb, Vt= Velocity Turn 

 

    Vc Vt Bf-109F:   250 290 Bf-109G-2/6:   260 280 Fw-190A-4:   270 340 Yak-1:   240 300 La-5:   255 330 LaGG-3 (29): 250 300

 

[SR-F_Winger]

OK - and?

[ShamrockOneFive]

Good reference for folks who are looking for best sustained turn times and speeds. If you've been flying for a while then you've probably already got these figured out but newer pilots I'm sure would appreciate the data.

[361fundahl]

So these are best climb speeds and best turn.speeds (as in max g??)

And by turn we mean pulling full back on elevator with plane sideways compared to horizon? Or pull back till you start to hear the heavy air pressure noise?

[SR-F_Winger]

Ah ok. Thanks OP!

[Finkeren]

Those numbers seem low tbh. Especially regarding climbing.

 

Doesn't fit my own experience in BoS (or any other sim for that matter) for most WW2 era fighters I've flown in IL2-1946, ClOD, BoS etc. the ideal climb is achieved somewhere between 300-375 km/h.

 

What is the source for these numbers?

[Willy__]

And by turn we mean pulling full back on elevator with plane sideways compared to horizon? Or pull back till you start to hear the heavy air pressure noise?

 

 

On velocity turn he means that you get the tighter turn radius if you make a turn at that speed. Is that what you were asking ? 

 

Finkeren, for the 109 I find it to be pretty much close, sometimes a little bit faster, but for the 190 I would say 300-310 is the best climb speed. But for the russian planes it seems low, imho. But I'm not an experten on the russian machines...

 

-edit-

 

Yep, confused the turn velocity with the climb one. They do seem rather low. For the 109s I would keep at 270-290 for climbing.

Edited January 14, 2015 by istruba

[361fundahl]

Yes much thanks!

I've been climbing my f4 at 240kph all along!

[Matt]

I would be very surprised if those climb speeds give the best climbrate. I would add at least 20 km/h for every one of those planes (and then they would also agree with historical flight tests in most cases).

[Felix58]

My feeling is that the numbers are on the low side.    

Does anyone else have any data on these factors?

[Finkeren]

I just did a little private testing (nothing too rigerous, so I won't post numbers for fear of confusing people) on the Yak and the 109F. While the turn speeds produced fairly good results (definately close enough to the best I could get at other speeds), for the climb speed it's not even close: Too slow by a rather large margin, and at 240 km/h the Yak is pretty much useless if you get into a fight right after levelling out effectively negating any advantage the higher climb rate might have given you (not that it did so) because you have to dive right away to regain your edge in maneuverability.

Edited January 15, 2015 by Finkeren

[II/JG17_HerrMurf]

Anecdotally, I've found the sweet spot to extend from both Yaks and La-5s is to pitch for 325 kph. In either the 109 or 190. If I pitch for 290-300 I am occasionally caught from behind but that could just be my poor flying.

[-TBC-AeroAce]

I climb around 270 for all fighters apart from 190 which seems happier around 300. This works well for me. For a more ballenced speed I cruse climb at around 350-400

[JohnHardtack]

Just an aside here. In RL flying, Vc=Design cruise speed, used to show compliance with gust intensity loading. It is known as a Regulatory V speed and is usually memorized by the pilot for the particular a/c that he/ she is flying. Vt has no definition in RL flying.

 

Vx=Speed that will allow for best angle of climb.

Vy=Speed that will allow for the best rate of climb.

 

I just bring this to your attention for the benefit of those concerned with reality.

Edited January 15, 2015 by JohnHardtack

[361fundahl]

Good info, thanks!

[Felix58]

Re Vc

This term is used as Velocity Corner Speed in Robert L. Shaw's excellent book - Fighter Combat - Tactics and Maneuvering.

Highly recommended for those interested in the technical aspects of Air Combat.  Not an easy read but comprehensive.

If you have a general flight sim interest "In Pursuit" by Johan Kylander is recommended.

[GP*]

Just an aside here. In RL flying, Vc=Design cruise speed, used to show compliance with gust intensity loading. It is known as a Regulatory V speed and is usually memorized by the pilot for the particular a/c that he/ she is flying. Vt has no definition in RL flying.

 

Vx=Speed that will allow for best angle of climb.

Vy=Speed that will allow for the best rate of climb.

 

I just bring this to your attention for the benefit of those concerned with reality.

Good explanations, but "Vt" does have a very real definition IRL. It just isn't called that.

 

There are numerous terms associated with various speeds for turn rates and radii. Most frequently referenced speeds are min sustain airspeed, max sustain airspeed, and corner velocity. Realize that these speeds vary based on altitude; if we could read Mach in this game, that would be a much more constant reference with varying altitude.

 

Max and min sustain are typically a tradeoff between turn rate and radii, and can even vary slightly from pilot to pilot based on technique and experience. Corner is more precise, and is the point where the awrodynamic lift limit meets the aircrafts G limit (ie below this speed full aft stick deflection will result in an accelerated stall, whereas above this will result in an over-G).

 

Disclaimer: everything above is offered as a friendly addition to this conversation. Some folks are under the impression that my posts are meant to be purely critical rather than constructive in nature.

[andyw248]

Most frequently referenced speeds are min sustain airspeed, max sustain airspeed, and corner velocity. (...)

Max and min sustain are typically a tradeoff between turn rate and radii, and can even vary slightly from pilot to pilot based on technique and experience. Corner is more precise, and is the point where the awrodynamic lift limit meets the aircrafts G limit (ie below this speed full aft stick deflection will result in an accelerated stall, whereas above this will result in an over-G). 

 

Interesting... But I have no clue how these speeds would be flown... My guess:

• Min sustain: Gear and flaps down, slow turn just above stalling (ie. ~135 in a 109)
• Max sustain: Gear and flaps down, high power, shallow bank to maintain high speed
• Corner velocity: Gear and flaps up, 60 - 70 degrees of bank, high power (ie. ~230 in a 109)

[=CFC=Conky]

Hello all,

 

If you want to use the WAG method (wild assed guess), the best rate of climb speed means your kite is producing close to it's maximum lift, therefore this speed will also give you good turn performance without having to overthink it too much, as useful thing when in combat.

[GP*]

<p>

 

Interesting... But I have no clue how these speeds would be flown... My guess:

• Min sustain: Gear and flaps down, slow turn just above stalling (ie. ~135 in a 109)
• Max sustain: Gear and flaps down, high power, shallow bank to maintain high speed
• Corner velocity: Gear and flaps up, 60 - 70 degrees of bank, high power (ie. ~230 in a 109)

Good additions, I didn't think about adding in any further explanation.

 

All of these speeds are fight-type airspeeds, so gear is up. Flaps may be used as a technique during min sustained. Power is typically at mil (or AB in modern fighters).

 

Just like the name states min and max sustained speeds are speeds that will generate acceptable/desirable turn performance when flown. They rely on the pilot performing a turn in an energy sustaining manner (which is the same as airspeed sustaining if the turn has no vertical component) in order to be effective. Min sustained airspeed is as slow as you want to get before your turn rate drops off dramatically (due to all lift being used nearly exclusively in the vertical component of lift if you get much slower), and before your turn radius opens up because you're no longer turning, you're just "flat plating" as they say. Max sustained typically generates a high number of degrees per second in turn rate, while giving an acceptable turn radius. Any faster and your turn circle opens up too much, and the G required to continue turning at the same degrees/sec will either over-G the pilot or cause the pilot to GLOC.

 

Corner is typically associated with instantaneous turn performance, where you simple want to turn as quickly and tightly as possible, and are willing to accept a significant energy bleed to achieve this. Corner is where you'll hit your max deg/sec, but it will be very short lived, because your speed will quickly drop off.

 

Energy sustaining maneuvers (referenced as airspeed sustaining above, because the conversation started with airspeeds) are typically associated with 2-circle fights, but are appropriate any time instantaneous turn performance isn't needed. Energy depleting type maneuvers are typically used to achieve a gunshot, deny a gunshot, or preserve 3/9 line advantage. Put another way: anytime you aren't doing one of those three things, you should either be sustaining or attempting to gain energy (but never at the cost of getting yourself into an enemy's gun WEZ).