Aces High Bulletin Board
Help and Support Forums => Help and Training => Topic started by: Demetrious on January 26, 2009, 11:07:43 PM
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Hello all,
Recently I've taken quite a shine to the P-40 in all it's iterations- the speed is somewhat lacking but it's roll rate is excellent and it seems capable of handling pretty much anything well (as long as you can sucker that FW-190 into a turn fight, that is.) There's just one little thing that has been driving me absolutely nuts.
The P-40 has an alarming tenancy to flip over and faceplant right into terra firma for no reason at all. This happens generally as I'm making a rather smooth (and not hard) turn, at around 150 MPH, or as I'm pulling out of a loop, at speeds of up to 200 MPH. She seems to want to roll left and stall, making me think it's an effect of torque, but sometimes she's okay with jerking around to the right, too. For reference, the P-40's stall speed is 90 MPH, and this phenomena is constantly observed at modest angles of attack- or no angle at all.
Naturally, this likes to strike just as I've won the rolling scissors or the like, and will unceremoniously flip my bird over and SLAM it into the earth just as I try to gently and smoothly take up a leisurely lag pursuit. As you may imagine, this makes me so mad I can barely breathe sometimes. Now, I've noticed this behavior consistently in both Aces High and IL-2 Sturmovik, so clearly I'm doing something wrong. I just can't imagine what. Do I need to give her some rudder opposite the direction of torque when undertaking maneuvers? Is torque in this bird worse then normal?
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I was practicing in the P-40 last week for FSO, and I can confirm that it will snap roll if your angle of attack is too great. The best thing you can do is simply not pull back so hard on the stick.
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I was practicing in the P-40 last week for FSO, and I can confirm that it will snap roll if your angle of attack is too great. The best thing you can do is simply not pull back so hard on the stick.
It's snap rolling with very low, gentle control input and very modest angle of attack- sometimes with no angle of attack. This starts around 150 MPH, which doesn't make much sense to me, because the P-40 stalls out near 90 and has always been described (in Real Life and in AH) as a good handler at low speeds.
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It's snap rolling with very low, gentle control input and very modest angle of attack- sometimes with no angle of attack.
You're grossly exaggerating here.
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You're grossly exaggerating here.
Not at all. This exact situation strikes, usually, when I'm coming out at the bottom of a short dive (having gone perfectly straight,) and the instant she feels control input, she snap-rolls. The other common scenario is just after I've won the rolling scissors, and my foe is trying to turn away. At about 130-50 MPH, just hanging there in the sky, having held her steady for at least two seconds with no AoA at all, as soon as I try to roll left/right and pull into a gentle lag pursuit (and I do mean gentle,) she rolls. Not a snap roll in that situation, but a nasty little lurch to the left (it's almost always the left, no matter which way I turn,) that requires heavy rudder and time to address, which lets my enemy slip away. The constant leftwards tendency is what makes me think it's some kind of torque effect.
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Film?
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Film?
I'll see what I can do, though it might not tell you much. Obviously the ship shouldn't be quite so prone to rolling, so I was expecting somebody to tell me that my joystick scaling is out of whack or the like. Or perhaps I need a bit of rudder in my turns.
As I said, this phenomena also appears in IL-2 Sturmikov, which has a flight model reasonably close to AH, so the fault clearly lies with something I'm doing.
Nobody minds mediafire for the hosting, I hope?
EDIT: Nevermind, I think I've solved it. I went to play with my joystick scaling and lo and behold, the X-axis didn't have scaling enabled for some funny reason. :huh Just an idiot, nothing to see here, move along...
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If it dipped one wing then flipped to the other, it sounds like maybe an accelerated stall (because you mention pulling out of a dive)
Keep in mind the P-40 will spin out pretty easily (not as bad as the P-39), so you have to watch her in rolling scissors, loops, and I don't recomment hammerhead manuvers at all. By the time you recover your enemy has killed you.
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EDIT: Nevermind, I think I've solved it. I went to play with my joystick scaling and lo and behold, the X-axis didn't have scaling enabled for some funny reason. :huh Just an idiot, nothing to see here, move along...
You must mean the Y-axis.
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Hello all,
Recently I've taken quite a shine to the P-40 in all it's iterations- the speed is somewhat lacking but it's roll rate is excellent and it seems capable of handling pretty much anything well (as long as you can sucker that FW-190 into a turn fight, that is.) There's just one little thing that has been driving me absolutely nuts.
The P-40 has an alarming tenancy to flip over and faceplant right into terra firma for no reason at all. This happens generally as I'm making a rather smooth (and not hard) turn, at around 150 MPH,as the angle of bank increases, so does your stall speed. almost sounds like you're getting a departure stall. or as I'm pulling out of a loop, at speeds of up to 200 MPH.this one, you may be exceeding the critical angle of attack, and stalling the wing. She seems to want to roll left and stall, making me think it's an effect of torque, but sometimes she's okay with jerking around to the right, too. For reference, the P-40's stall speed is 90 MPH, and this phenomena is constantly observed at modest angles of attack- or no angle at all. don't forget.....the angle of attack as far as your airplane is concerned is to the oncomming wind. thus, if you're in a 40 degree dive, and yank the plane to a 20 degree dive suddenly, you've just exceeded the wings angle of attack.
Naturally, this likes to strike just as I've won the rolling scissors or the like, and will unceremoniously flip my bird over and SLAM it into the earth just as I try to gently and smoothly take up a leisurely lag pursuit. As you may imagine, this makes me so mad I can barely breathe sometimes. Now, I've noticed this behavior consistently in both Aces High and IL-2 Sturmovik, so clearly I'm doing something wrong. I just can't imagine what. Do I need to give her some rudder opposite the direction of torque when undertaking maneuvers? Is torque in this bird worse then normal?
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It's snap rolling with very low, gentle control input and very modest angle of attack- sometimes with no angle of attack. This starts around 150 MPH, which doesn't make much sense to me, because the P-40 stalls out near 90 and has always been described (in Real Life and in AH) as a good handler at low speeds.
also.....is that 90 mph stall speed clean, or dirty?
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IL-2 Sturmikov, which has a flight model reasonably close to AH
:huh
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What flight controller are you using?
Wings level, if you pull back on the stick hard enough, it'll snaproll neat as you please. But only if you pull back hard- or have a spike.....
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What flight controller are you using?
Wings level, if you pull back on the stick hard enough, it'll snaproll neat as you please. But only if you pull back hard- or have a spike.....
yes...that is creating the departure stall. the wing is at that point exceeding the critical angle of attack.
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The P-40 has an alarming tenancy to flip over and faceplant right into terra firma for no reason at all. This happens generally as I'm making a rather smooth (and not hard) turn, at around 150 MPH, or as I'm pulling out of a loop, at speeds of up to 200 MPH. She seems to want to roll left and stall, making me think it's an effect of torque, but sometimes she's okay with jerking around to the right, too. For reference, the P-40's stall speed is 90 MPH, and this phenomena is constantly observed at modest angles of attack- or no angle at all.
As everyone so far has eluded to, but not yet stated in the clear, It’s not the airspeed, a stall is totally dependent on the Angle of Attack (AOA) of the Relative Wind (RA) and not the speed of the aircraft.
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As everyone so far has eluded to, but not yet stated in the clear, It’s not the airspeed, a stall is totally dependent on the Angle of Attack (AOA) of the Relative Wind (RA) and not the speed of the aircraft.
I WAS FIGHTing against humble.....him in an sbd, me in a p38g.........got into a rolling scissors with him. it was stupid of me to fall into his fight.......but i digress. i was juuuuuuussssst getting him to go out front ever so slightly. then, i got a quick shudder, and the ole 38 o deth snapped in the opposite direction i was rolling in. it took me 3k to recover the ensueing spin, and when i did, he was waiting for me....and smoked the poopoo outta me.
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You're grossly exaggerating here.
Hyperbole is the word your looking for ;)
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I WAS FIGHTing against humble.....him in an sbd, me in a p38g.........got into a rolling scissors with him. it was stupid of me to fall into his fight.......but i digress. i was juuuuuuussssst getting him to go out front ever so slightly. then, i got a quick shudder, and the ole 38 o deth snapped in the opposite direction i was rolling in. it took me 3k to recover the ensueing spin, and when i did, he was waiting for me....and smoked the poopoo outta me.
Snap is great in that SBD. I'm always amazed at how well he fights in that ol' bird. Kinda scary too.
Back on topic:
As far as fighting in the P-40. Find/PM FiLtH. He frequents these boards and flys the E model quite often. If you ask him nicely, he might help you out. Also, try a search of the BBS. I think this was discussed some time last year too. And FiLtH did jump in and give some P-40 tips.
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You must mean the Y-axis.
No, I do mean the x-axis, my roll axis. Mind you, my y-axis DID have scaling enabled, so I think that was giving some funky inputs. Brief testing seems to show that it's somewhat improved.
:huh
They're in the same ballpark waving at each other. Kind of. Cept where AA will spank you, IL-2 will slay you while laughing wickedly.
s everyone so far has eluded to, but not yet stated in the clear, It’s not the airspeed, a stall is totally dependent on the Angle of Attack (AOA) of the Relative Wind (RA) and not the speed of the aircraft.
Relative airflow over the airfoil, yeah. But in these situations, it should have been sufficient...
also.....is that 90 mph stall speed clean, or dirty?
Clean, but come to think of it, in at least some of those situations I had two notches of combat flaps dropped. Some. It's quite possible that the P-40 just doesn't play nice with flaps when you're low on E.
As far as fighting in the P-40. Find/PM FiLtH. He frequents these boards and flys the E model quite often. If you ask him nicely, he might help you out. Also, try a search of the BBS. I think this was discussed some time last year too. And FiLtH did jump in and give some P-40 tips.
Excellent. I'll go track down the thread now.
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Snap is great in that SBD. I'm always amazed at how well he fights in that ol' bird. Kinda scary too.
Back on topic:
As far as fighting in the P-40. Find/PM FiLtH. He frequents these boards and flys the E model quite often. If you ask him nicely, he might help you out. Also, try a search of the BBS. I think this was discussed some time last year too. And FiLtH did jump in and give some P-40 tips.
1duke1 is anohter kickarse p40 driver.....
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No, I do mean the x-axis, my roll axis. Mind you, my y-axis DID have scaling enabled, so I think that was giving some funky inputs. Brief testing seems to show that it's somewhat improved.
They're in the same ballpark waving at each other. Kind of. Cept where AA will spank you, IL-2 will slay you while laughing wickedly.
Relative airflow over the airfoil, yeah. But in these situations, it should have been sufficient...it's not dude.....i think even on fighters, the critical angle of attack is only about 17 degrees. exceed that, and you get what you got.
Clean, but come to think of it, in at least some of those situations I had two notches of combat flaps dropped. Some. It's quite possible that the P-40 just doesn't play nice with flaps when you're low on E.
Excellent. I'll go track down the thread now.
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.it's not dude.....i think even on fighters, the critical angle of attack is only about 17 degrees. exceed that, and you get what you got.
I was barely pulling ten in most of those cases, but being slow and dirty might have cinched it. I micromanage flaps a lot, and perhaps I'm not giving them enough time to return to neutral position before pushing my luck? I think that has to be it. The critical AoA is lower at low speeds (less airflow over the airfoil, natch,) and with flaps thrown in...
Besides this little issue though, the P-40E is a wonderful bird. Anything it can't out-turn it can generally out-roll, or vice versa. The psychological factor can't be dismissed, either.
Per Obie's suggestion I searched around a bit with Filth's name in the filter and his old posts seemed to confirm that the P-40 is a right touchy bird at low speeds, so my theory is simply that I haven't been keeping track of my combat flaps enough and the P-40 is very unforgiving of being dirty at low E.
EDIT: Well, Widewing, in this post (http://bbs.hitechcreations.com/smf/index.php/topic,200358.msg2349569.html#msg2349569) says the P-40 has the "worst stall departure of any AHII fighter," and that it "wallows like a drunk below 150 MPH" (which is percisely where my problems tend to hit) so I guess that's all there is to it.
And you're all lovely for not pointing out that I'm just a moron who forgot to use search. Thanks, that was lovely of y'all :o
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Per Obie's suggestion I searched around a bit with Filth's name in the filter and his old posts seemed to confirm that the P-40 is a right touchy bird at low speeds, so my theory is simply that I haven't been keeping track of my combat flaps enough and the P-40 is very unforgiving of being dirty at low E.
I'm pretty sure the P-40 has split flaps. They tend to be next-to-worthless for combat in aircraft with such a poor thrust:drag ratio. In the tests I've done the P-40's turn rate decreases with the use of flaps.
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I'm pretty sure the P-40 has split flaps. They tend to be next-to-worthless for combat in aircraft with such a poor thrust:drag ratio. In the tests I've done the P-40's turn rate decreases with the use of flaps.
Interesting. They seem to help me, but then again I'm usually making either slow wide turns to keep my E high or hard break turns into somebody that I don't intend to sustain, so I've never really put them to the test in a proper turnfight. (The P-40s can dump speed nicely in the scissors, but that Allison sure as heck isn't going to get it back for you in a hurry. :uhoh)
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And you're all lovely for not pointing out that I'm just a moron who forgot to use search. Thanks, that was lovely of y'all :o
no reason to do that to ya...you asked a good question, and there were a lot of good answers for us all to read, and learn from.
these are the kinds of posts that are good and fun to read.
<<S>>
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You may think you are turning gently, but it will flick over at the drop of a hat. Lock your wrist so you dont create any little tweak of motion that will cause it to auger. At slow speed be at full flaps, always ready to raise them at any nose down to gather more speed. Let the flaps do your turning for you.
Say you are chasing guys tail and he goes slightly nose up. Lets say you are 1 notch of flap. Gently follow and lead him a bit, and walk the flaps up. This will raise the nose to give you the shot you need without pressing the plane and stalling.
Give the p40e a month of constant play and you'll rarely use another plane. Ive been flying the 110g alot lately for a change and fly it the same way. To me most of the US stuff acts similar to eachother in use of flaps except maybe the F6. The P47s,F4u,P40,51s all seem to behave the way I prefer as far as flaps go.
Remember with the P40E, flaps are what make it what it is. Probably why its almost always the thing you lose first from damage. Each plane seems to have its favorite damage loss..flaps is the P40E's. Dont add them to soon..1 notch at outset of fight, and only more if it gets slow. If it does get slow use full flap to end the fight as soon as possible so you can set up to evade the next guy that sure to be on you. Also when in a fight...the time before its a committed slow fight, and the enemy is trying to sucker your E, flap up and down often as needed. Its all timing and gauging when you can commit.
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Wow, that's a very different impression. I only flew the P-40 intensively for about a week so I'm going to take Filth's word on this one and re-check the flaps on the P-40. On the other hand, I agree that it loses flaps to damage before anything else.
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FiLtH, you never disappoint us! :aok :salute
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Here are the stats for a complete 360 in seconds, P-40E with 75% fuel:
No flaps: 19.7
1 notch: 18.7
2 notches: 18.6
3 notches: 18.6
4 notches: 20.3
These numbers are approximate, of course, so its best turn-rate is somewhere in the range of 1-3 notches of flaps. I would guess that 2 notches is optimal, but if you need to decrease your radius go with 3. 4 notches of flaps yields the worst sustained turn-rate, and so I would only go that far if I were trying to force an overshoot.
For comparison's sake, here are the sustained 360 times of typical main arena aircraft:
Spit XVI 15.8
N1K2 16.8
P51D 20.0
F4U-1A 17.6
109 K-4 18.6
Hurri IIC 15.7
P38L 18.1
The trick is to figure out how much decreasing your radius can offset increasing your turn-rate. For instance, the F4U-1A is known for giving the SpitXVI fits even though the SpitXVI turns faster simply because the Corsair makes a smaller circle.
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The fourth I use for the lift not so much the turn. Fighting Spit9s with that better climb it comes in handy thru the turn.
Another handy practice technique would be to take the 40 nose up to stall, and practice snapping opposite rudder when it falls off and starts to spin. You can do some real slow crazy stuff in it. If you find yourself at risk of scraping yer belly on the ground, train yourself not to yank the stick. It tends to just make it worse, like most planes in here. Try adding flap instead, and just a steady hold on the stick.
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The P-40 certainly has some interesting flight characteristics that present themselves in the low speed/high AOA area of the flight envelope. From my experience the onset of the stall is relatively predictable with a moderate break. It does snap/spin quickly though if you're ham fisting it, especially if uncoordinated - but seems to be easily recoverable in most situations. It seems that it often wants to fall flat or tail first if you let it, seems as if it has a very aft center of gravity. All that is usually coupled with considerable yawing moment as well, depending on how you enter the stall/spin and the rudder becomes very sluggish to stop the slow/lazy lateral oscillations of the nose. The nose certainly wallers around at slow speed and demands a lot of rudder input to keep it coordinated and keep the stall departures under control. I usually use full flaps when stall fighting.
Overall I think it's a relatively easy airplane to fly on the edge/stall fight, just have to keep it coordinated. It has a lot of adverse yaw at slow speeds if not coordinated and that really aggravates the departure/stall. Yawing moment is the major ingredient in the stall/spin equation, and when not flown properly the P-40 certainly produces a lot of it.
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I'm pretty sure the P-40 has split flaps. They tend to be next-to-worthless for combat in aircraft with such a poor thrust:drag ratio. In the tests I've done the P-40's turn rate decreases with the use of flaps.
Every fighter's turn rate decreases with flap use....
My regards,
Widewing
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Every fighter's turn rate decreases with flap use....
My regards,
Widewing
Have you tested that assumption? I have. ;)
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Have you tested that assumption? I have. ;)
Does the Pope know Latin? :huh
Any time you reduce speed below corner velocity, your turn rate suffers. With the exception of the P-47s, P-51s and P-40s, every aircraft that deploys even one notch of flaps will be below corner velocity, or below corner velocity an instant later. The above mentioned will be below corner in about two seconds if pulling more than 3g. The vast majority of fighters can't begin to lower flaps until below corner velocity. So, their turn rate is already below optimum.
To determine corner velocity and the effect flaps have on turn rate and radius, you need Badboy's Bootstrap Calculator found here: http://www.badz.pwp.blueyonder.co.uk/Academy/AH_BootStrap.zip (http://www.badz.pwp.blueyonder.co.uk/Academy/AH_BootStrap.zip)
Then, you need to record speed and time when turning the tightest circles you can manage. I recommend doing no less than 3 circles, taking the average of time and speed. Plug this data into Badboy's calculator and you'll have the data you require. Do it for clean and for each flap position. You will notice that sustained turn rate is much, much less than that at corner velocity. Adding flaps further reduces speed, and turn rate follows it down.
Once you grasp what Badboy's calculator is telling you, you'll see that flap usage is something you'll want to manage very carefully.
My regards,
Widewing
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I'm pretty sure the P-40 has split flaps. They tend to be next-to-worthless for combat in aircraft with such a poor thrust:drag ratio. In the tests I've done the P-40's turn rate decreases with the use of flaps.
The turn rate **DECREASES** with flaps??? I want to make sure I read that... DECREASES? Then what I have known to be true with the P40E for over a year is bogus. Why oh Why!? ;) I've been lowering 1 notch for quite some time while turn fighting, seems to help.
The one thing I ask is.. how many turn OFF the combat trim while dogfighting in the P40E? If I am able to get it 250mph+, I turn it off. It seems to stall out quicker when on and menouvering at low speed,... or is it just me?
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The turn rate **DECREASES** with flaps??? I want to make sure I read that... DECREASES? Then what I have known to be true with the P40E for over a year is bogus. Why oh Why!? ;) I've been lowering 1 notch for quite some time while turn fighting, seems to help.
The one thing I ask is.. how many turn OFF the combat trim while dogfighting in the P40E? If I am able to get it 250mph+, I turn it off. It seems to stall out quicker when on and menouvering at low speed,... or is it just me?
Read the thread. One notch or two does seem to help the P-40, but for many other aircraft that have split flaps they do not help.
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The turn rate **DECREASES** with flaps??? I want to make sure I read that... DECREASES? Then what I have known to be true with the P40E for over a year is bogus. Why oh Why!? ;) I've been lowering 1 notch for quite some time while turn fighting, seems to help.
The one thing I ask is.. how many turn OFF the combat trim while dogfighting in the P40E? If I am able to get it 250mph+, I turn it off. It seems to stall out quicker when on and menouvering at low speed,... or is it just me?
As Widewing said, best turn rate is a corner velocity (which can't be sustained without altitude loss, and is typically above flap deployment speed). If we're talking sustained rate of turn, the effect of flaps varies from plane to plane, but for the p40E, the best sustained rate is at one notch.
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As Widewing said, best turn rate is a corner velocity (which can't be sustained without altitude loss, and is typically above flap deployment speed). If we're talking sustained rate of turn, the effect of flaps varies from plane to plane, but for the p40E, the best sustained rate is at one notch.
I've been using one notch only in tight turns and it seems to make the difference, at least for me, in lasting a bit longer in a dog fight. ;)
I need to learn some of the other lesser known tricks, because as soon as I lose the advantage I lose the fight since receovering is up to the other guy making a mistake.
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Hello all,
Recently I've taken quite a shine to the P-40 in all it's iterations- the speed is somewhat lacking but it's roll rate is excellent and it seems capable of handling pretty much anything well (as long as you can sucker that FW-190 into a turn fight, that is.) There's just one little thing that has been driving me absolutely nuts.
The P-40 has an alarming tenancy to flip over and faceplant right into terra firma for no reason at all. This happens generally as I'm making a rather smooth (and not hard) turn, at around 150 MPH, or as I'm pulling out of a loop, at speeds of up to 200 MPH. She seems to want to roll left and stall, making me think it's an effect of torque, but sometimes she's okay with jerking around to the right, too. For reference, the P-40's stall speed is 90 MPH, and this phenomena is constantly observed at modest angles of attack- or no angle at all.
Naturally, this likes to strike just as I've won the rolling scissors or the like, and will unceremoniously flip my bird over and SLAM it into the earth just as I try to gently and smoothly take up a leisurely lag pursuit. As you may imagine, this makes me so mad I can barely breathe sometimes. Now, I've noticed this behavior consistently in both Aces High and IL-2 Sturmovik, so clearly I'm doing something wrong. I just can't imagine what. Do I need to give her some rudder opposite the direction of torque when undertaking maneuvers? Is torque in this bird worse then normal?
I can agree with it having an addiction to rolling when you make a tight turn at around 120 - 200mph, its mostly cause you might be pulling your stick back toward yourself to hard; otherwise, im not sure.
-FYB