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XyZspineZyX
08-08-2003, 04:31 PM
How do I get the values for corner velocity for varoius airplanes? Is it possible to find a kind of table somewhere or should I use the max speed and calculate somehow?

XyZspineZyX
08-08-2003, 04:31 PM
How do I get the values for corner velocity for varoius airplanes? Is it possible to find a kind of table somewhere or should I use the max speed and calculate somehow?

XyZspineZyX
08-08-2003, 05:04 PM
Bump, I too would like to know if there is a way to determine best corner velocity-

I'm going by feel/experience at the moment but that involves a lot of flying on one type only; if there's a way to (fairly) easily determine this, please share /i/smilies/16x16_smiley-happy.gif

Cheers,
Cold_gambler

XyZspineZyX
08-08-2003, 08:42 PM
Bump... noone knows?

XyZspineZyX
08-08-2003, 09:11 PM
bump. any kind people willing to share here or is it just full of folks looking for an advantage over others......

http://perso.wanadoo.fr/yak11/autresyaks/df002.jpg

"Anytime you have an opportunity to make things better and you don't, then you are wasting your time on this earth." -Roberto Clemente

XyZspineZyX
08-08-2003, 10:30 PM
If you are refering to the speed at which an aircraft will turn the best there is a formula for it but I cant remember it off the top of my head and I lost the notes it was in, sorry. But it is to do with the relationship between the angle of bank, the lift produced by the wing, the forward speed and the number of 'G's pulled in the turn, and the turn radius. If this is what you are after I can find out so let me know.

"They Gave All Their Tommorrows So That We Can Have Our Todays"

XyZspineZyX
08-08-2003, 10:50 PM
Corner velocity is interesting only for instantaneous turns, it cannot be sustained. Much more relevant is speed in best sustained turns. If you're interested about a particular aircraft I can answer, just give me the name. Otherways there is a simple rule of thumb, early war aircraft around 260kmh, mid and late war aircraft with less than 1800hp around 300kmh, those having more than 1800hp around 340-350kmh.

XyZspineZyX
08-08-2003, 11:08 PM
hey VonShloganoff
yep, that's it. If you could dig up that info for us it'd be great! /i/smilies/16x16_smiley-happy.gif

in the meantime, here's a little something I found in a google search:

"Take me at my word when I tell you that turn radius is proportional to the square of the airspeed and inversely proportional to the number of Gs pulled [R V2/n]. When the airspeed goes up, the turn radius increases very quickly if we hold Gs constant. Hold the airspeed constant and the turn radius decreases when the load factor goes up. Contrast this to the relationships for turn rate. Turn rate (*) is inversely proportional to airspeed [* n/V] and proportional to Gs. As you go faster, turn rate decreases. Conversely, the turn rate increases as you pull more on the pole.

To maximize turn performance, we need to minimize our turn radius and maximize our turn rate. Doing both of these things will also minimize the altitude loss. Optimal turn performance will occur when we pull lots of Gs at a slow airspeed. Let's look at the V-n diagram again. Ignoring gravity for now, the turn radius stays pretty fairly constant along the stall line since we increase available G much faster than we increase airspeed. In other words, turn radius is proportional to the square of the airspeed and inversely proportional to the G pulled. G available is also just about proportional to the square of the airspeed, so the airspeed increase cancels out and turn radius stays relatively constant as long as you're pulling to the aerodynamic limit. Once we reach the +6 G structural limit, the turn radius begins to rapidly increase since we're holding allowable G constant while continuing to increase the airspeed. It would seem, then, that our minimum turn radius could be obtained by flying anywhere along the stall line. Figure 2 is a plot of turn radius vs. airspeed, given that the G for the airspeed is the maximum allowed by aerodynamics or structure. Once the T-3's 6 G structural limit is reached at 156 knots, the radius begins to increase."

Which was excerpted from here: http://safety.kirtland.af.mil/magazine/htdocs/junmag98/pullout.htm

An interesting (and as far as I can tell, accurate) article.

I guess Skychimp et al are on vacation... where are those guys when you need 'em? /i/smilies/16x16_smiley-tongue.gif

Cheers,
Cold_gambler

XyZspineZyX
08-08-2003, 11:14 PM
Huck has a good point. You can find corner velocity several places on the web, do a google search in advanced..

Here is on pic from combatsim.com:

http://www.combatsim.com/archive/images/img_arc-15/bbcc-em1.gif


or:

http://www.combatsim.com/htm/nov98/tactic/energy2-109.jpg



Corner Velocity is the minimum speed for the highest G turn (typically 9 g's, but in WW2 planes, limited at lower G's, and/or pilot blackout). It is not the "sustained" turn rate which also important in ACM.

To determine it for a plane, you generate the above E-M charts. You need to time turns to establish degrees/second and find the speeds where you have either low speed stall or high speed stall.

or here at simhq.com:

http://www.simhq.com/_air/air_039a.html



" The first time I ever saw a jet, I shot it down ": General Chuck Yeager, USAF, describing his first confrontation with a Me262 - - -
" Aggressiveness was a fundamental to success in air-to-air combat and if you ever caught a fighter pilot in a defensive mood you had him licked before you started shooting ": Captain David McCampbell, USN, leading U.S. Navy ace in W.W.II.

XyZspineZyX
08-08-2003, 11:19 PM
Websites/history channel/object file are ok if you are writing a book, but if you are looking for the characteristics of the planes in the sim you have to find out for yourself (test the planes as they are in the sim)

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"The Force is strong with this one." -What an ace said of RayBanJockey during a fight when he was still a newbie.
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XyZspineZyX
08-08-2003, 11:31 PM
Twigtoto,

I bow down to your googling abilities! lol
Thanks for posting that.

Thanks Huckebein- thanks for the rule of thumb /i/smilies/16x16_smiley-happy.gif

RBJ, point taken; but are you not sharing the details on each ac 'cause your saving that kind of info for your book?

Cheers all /i/smilies/16x16_smiley-happy.gif
Cold_gambler

XyZspineZyX
08-08-2003, 11:32 PM
Cold_Gambler wrote:
-
- I guess Skychimp et al are on vacation... where are
- those guys when you need 'em?


Don't expect from Skychimp any answer, he consistently proved that he can't answer anything regarding aircraft aerodynamics.
Calculating corner velocity is incredibly simple, but as I said before it's not very useful. Corner velocity is telling only the speed at which you should begin the hard turn (this is a luxury you don't have usualy) and it does not tell anything about the speed plane can sustain (see the rule of thumb above).

in short:

corner velocity = stall_speed * 2.66

Yeah that's all.

For example
Bf-109G early: 100 * 2.66 = 266 mph
P-47D early: 115 *2.66 = 306 mph

and so on.

Message Edited on 08/08/0305:59PM by Huckebein_FW

XyZspineZyX
08-09-2003, 12:01 AM
Skychimp is good at digging up obscure technical information, and he has a cute monkey sig /i/smilies/16x16_smiley-happy.gif


I won't say anything more /i/smilies/16x16_smiley-wink.gif

XyZspineZyX
08-09-2003, 12:09 AM
Cold_Gambler wrote:
-
- Skychimp is good at digging up obscure technical
- information, and he has a cute monkey sig


We can agree about that (except the monkey sig part, which I find distasteful, but hey, what do I know about monkeys?)

XyZspineZyX
08-09-2003, 12:14 AM
sig test


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XyZspineZyX
08-09-2003, 12:30 AM
Hucks right about corner velocity in prop planes being kinda useless, If i am allowed to paraphrase.

Corner velocity is really only usefull in jets. Dobbs, my F-15 pilot friend, says corner velocity in props doesn't hold up and doesn't apply anywhere as well as it does for jets.

Sure was good to see that WB 1.11 chart for the 109F! That was a great ride in that sim at that time, so much other pilots called you names if you flew it. Loved that time in WB, would have to call it the golden time for me.


BTW, remember Janes ATF? It had a carret in the HUD to show corner velocity for every plane in it's inventory. Was a nice "cheat".

XyZspineZyX
08-09-2003, 01:05 AM
1st I'd like to compliment you nice people volunteering so much help! (last time i asked a question like this the nicest answer i got was like RBJs )

OK, now Huck, how do you figure out best sustained turn rate ? Oh and your guidelines are most helpfull especially as i can never seem to settle on any one particular plane.
I'm just curious what the formula looks like & is there a
V* designation that repreesnts this ?

ps havent had time to read all the nice links provided etc but looking forward to it.
S!

http://perso.wanadoo.fr/yak11/autresyaks/df002.jpg

"Anytime you have an opportunity to make things better and you don't, then you are wasting your time on this earth." -Roberto Clemente

XyZspineZyX
08-09-2003, 01:19 AM
The most important speed you can know for turning is the sustained speed if you were near the ground ... what would make you do a complete circle the fastest.

This is often what turning fights come down to, because as long as you have altitude you can use it to evade. But eventually you both may wind up near the ground, and then whoever knows their numbers best will usually win

Like in CFS1, for the Hurricane, it was about 160-165mph. You could turn tighter and get it down to 120-130mph, but the person who did 160mph would win. So there is a speed you don't want to go below (don't turn too hard) that is different for each plane.

You can learn from experience but the best way would be to record tracks and do different speeds and then watch them later and record the values.

<img src=http://lafayettefederation.com/screenshots/repository/turo/tn-Numbaone.jpg>
"The Force is strong with this one." -What an ace said of RayBanJockey during a fight when he was still a newbie.
<a href=http://www.theinformationminister.com/press.php?ID=612109283>news update</a>

XyZspineZyX
08-09-2003, 08:59 AM
For those intrested in Formulas and Technical Howtos check this side.

http://web.ew.usna.edu/~dfr/technical_flying.html

The main problem in FB is to get usefull data from it.
A simple x,y,speed, aoa , alt , bank angle ,engine torque , position of all rudders , fuelstate , current airpressure ,loadout etc printout is not possible so its all about best guess.

(And hope the FM is correct)






Message Edited on 08/09/0308:01AM by BBB_Hyperion

Tully__
08-09-2003, 09:09 AM
Far more important than corner velocity is relative turn perfomance. Can I turn better than the other guy at this speed? If not, will going faster or slower improve my turn? If slower, will the increased turn performance be sufficient to finish my opponent before the loss of energy leaves me helpless before his guns?



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Salut
Tully

XyZspineZyX
08-09-2003, 09:35 AM
A good trick if you are in a 109 vs a Yak is to turn with him (just to see if he is a noob not using trim) and if you feel you are starting too loose the loops then pull up into a zoom climb, riding the prop pitch up to 100. He can't follow, then you drop down on him and he will have no choice but to run/evade and call you a cheat.

<img src=http://lafayettefederation.com/screenshots/repository/turo/tn-Numbaone.jpg>
"The Force is strong with this one." -What an ace said of RayBanJockey during a fight when he was still a newbie.
<a href=http://www.theinformationminister.com/press.php?ID=612109283>news update</a>

XyZspineZyX
08-09-2003, 09:56 AM
Tully__ wrote:
- Far more important than corner velocity is relative
- turn perfomance. Can I turn better than the other
- guy at this speed? If not, will going faster or
- slower improve my turn? If slower, will the
- increased turn performance be sufficient to finish
- my opponent before the loss of energy leaves me
- helpless before his guns?
-

Well never the less important is the other guy in the mood to turn or to slow down ? Does the sustained turn bleed more E than a high/low yoyo ? Is turning in this planetype advisable at all ? Is the current E State high enough to play hang on the prop with him ? etc .. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

XyZspineZyX
08-09-2003, 09:59 AM
I will try to find it but I am not promising anything. It is in a book called: Theory of Flight By A.C.Kermode, or somthing like that.

"They Gave All Their Tommorrows So That We Can Have Our Todays"