Author Topic: P-38 dive flaps produce no drag  (Read 13807 times)

Offline Sunka

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Re: P-38 dive flaps produce no drag
« Reply #75 on: March 19, 2014, 07:03:19 AM »
Seems like if it was anything but a bug someone at HTC would have been along by now.
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Offline nrshida

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Re: P-38 dive flaps produce no drag
« Reply #76 on: March 19, 2014, 07:24:34 AM »
You and hlbly have both made the same contribution to this thread. You both made personal attacks for no reason other than spite. Now I'm thinking you don't know what irony is.  :lol

Not personal it's a criticism of your methods. Why would we need to be spiteful? You were the one who was wrong.

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Offline Hoplite

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Re: P-38 dive flaps produce no drag
« Reply #77 on: March 19, 2014, 07:44:49 AM »
Nah. Real men fly the one-ten...  :aok

I knew there was a reason I liked you.  :D  :aok

FYI - I like you too, Triton.  I simply choose to overlook your love for the B-38.   ;)

Offline Randy1

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Re: P-38 dive flaps produce no drag
« Reply #78 on: March 19, 2014, 08:14:36 AM »
I think Cactus's post in the other P-38 thread made it clear that there is some drag even at low speeds and it limits your top speed. Is it a bug or a wishlist item? I expect there's a good reason it's not already modeled, along with a trim change, even if it turns out it should be.

Sure some drag but small below transonic speed.  How small?  We don't know.  And the OP assumes you deploy the flap and continue on without diving which would be pilot error.  What the OP should ask is Mach drag in the model?  A much larger issue.

Again keep in mind the dive flap will only produce appreciable lift if the top wing breaks continuous laminar flow.  Then the flap is deployed breaks breaks laminar flow on the bottom of the wing to counter.  Another way to put it is, without the dive flap, the bottom of the wing has more negative lift than the top wing has positive lift in transonic flow.

Offline hlbly

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Re: P-38 dive flaps produce no drag
« Reply #79 on: March 19, 2014, 08:53:13 AM »
Not personal it's a criticism of your methods. Why would we need to be spiteful? You were the one who was wrong.


In a world constantly changing wouldn't it be nice for just once . The bad things change and the good stay the same? I never could state it as eloquent as you my friend.

Offline colmbo

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Re: P-38 dive flaps produce no drag
« Reply #80 on: March 19, 2014, 09:32:58 AM »
And the OP assumes you deploy the flap and continue on without diving which would be pilot error. 

No he didn't.  He pointed out that the dive recovery flap doesn't seem to have any drag modeled and he is certainly correct that there should be some degree of speed decrease if the flap is extended.

I don't feel that having the drag modeled will make a huge increase in game, the only folks who will notice it will be the ones who forget to retract it and lose some speed when level.
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Offline GScholz

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Re: P-38 dive flaps produce no drag
« Reply #81 on: March 19, 2014, 10:32:16 AM »
As it is now you can just extend the flap before rolling and leave it out, never bother with it. If that was HTC's intention when adding the dive flaps then why did they make it a manually operated item in the game? Seems to me they intended for it to be used only when needed like it was in real life, but for some reason the drag and other consequences for having them deployed below Mach .68 was not modeled.
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Offline Randy1

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Re: P-38 dive flaps produce no drag
« Reply #82 on: March 19, 2014, 10:56:55 AM »
As it is now you can just extend the flap before rolling and leave it out, never bother with it. If that was HTC's intention when adding the dive flaps then why did they make it a manually operated item in the game? Seems to me they intended for it to be used only when needed like it was in real life, but for some reason the drag and other consequences for having them deployed below Mach .68 was not modeled.

I do see your and Columbo's point.  But, maybe it is modeled but not enough measurable difference in the game as GScholz points out in his reply that the dive flap is left on all of the time(The pilot error I was referring to). 

Again actuation in the subsonic region is a mute point as there is no document that shows the change in drag coefficient with the flaps down that I have seen.  We can only guess it will change but the antidote information out there suggest sub transonic region there is no notable lift.  Also note that if a notable speed reduction occurred, then i think we would have found antidote type evidence at least in place of hard numbers.

My WAG again is the P-38L is modeled with the best hard-fact information available to the coder.  If someone has additional hard facts then let them come forward.

What this thread did do was advance our knowledge of why the dive flap was designed the way it is.  My  :salute to GScholz for that.

Offline nrshida

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Re: P-38 dive flaps produce no drag
« Reply #83 on: March 19, 2014, 11:41:01 AM »
My WAG again is the P-38L is modeled with the best hard-fact information available to the coder.

I think it is more likely an oversight as an unfortunate side effect of flight modeling and graphical modeling being separate.



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Offline danny76

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Re: P-38 dive flaps produce no drag
« Reply #84 on: March 19, 2014, 11:43:14 AM »
I think someone who finds a bug no one has found before deserves a compliment. I think someone who does nothing but look for opportunities to demonstrate how correct they are about nothing particularly special as a platform to talk down to people without making a genuine contribution and even derail technical threads to do this should be criticized.   :aok



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Offline FLS

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Re: P-38 dive flaps produce no drag
« Reply #85 on: March 19, 2014, 05:32:55 PM »
Not personal it's a criticism of your methods. Why would we need to be spiteful? You were the one who was wrong.



You didn't post anything showing I was wrong. You just keep saying it.  You're not criticizing my methods you're criticizing my opinions. You don't agree, you obviously can't argue subjects you don't begin to understand, and you can't handle that gracefully.
« Last Edit: March 19, 2014, 07:54:42 PM by FLS »

Offline nrshida

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Re: P-38 dive flaps produce no drag
« Reply #86 on: March 20, 2014, 02:29:55 AM »
You didn't post anything showing I was wrong. You just keep saying it.  You're not criticizing my methods you're criticizing my opinions. You don't agree, you obviously can't argue subjects you don't begin to understand, and you can't handle that gracefully.

Ah good, an opportunity to demonstrate I do understand irony: you're still butt-hurt from being shown to be wrong about a year ago and you're implying it's the other parties that can't handle things gracefully. Now that's irony!  :lol

I don't agree with your opinion that the drag was not overlooked because I suspect intuitively it will be more than the trivial amount you're implying it is, but actually in this case I'm more criticising your argumentative and irrelevantly pedantic approach (which incidentally derails threads) just to try and make yourself look superior.

For instance this is now something like the fifth opportunity you've taken to imply I am unable to understand the subject because I'm not as intelligent as you. Despite your continual implication that you think you've made only positive contributions to this topic I've still seen no original effort on your part to actually quantify the drag.


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Offline FLS

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Re: P-38 dive flaps produce no drag
« Reply #87 on: March 20, 2014, 04:16:40 AM »
Ah good, an opportunity to demonstrate I do understand irony: you're still butt-hurt from being shown to be wrong about a year ago and you're implying it's the other parties that can't handle things gracefully. Now that's irony!  :lol

I don't agree with your opinion that the drag was not overlooked because I suspect intuitively it will be more than the trivial amount you're implying it is, but actually in this case I'm more criticising your argumentative and irrelevantly pedantic approach (which incidentally derails threads) just to try and make yourself look superior.

For instance this is now something like the fifth opportunity you've taken to imply I am unable to understand the subject because I'm not as intelligent as you. Despite your continual implication that you think you've made only positive contributions to this topic I've still seen no original effort on your part to actually quantify the drag.




You are referring to the haptic thread where hlbly admitted that the tests he did, on the AH version prior to the FFB update, did in fact prove that everything I claimed about it was correct. Then, not having gotten the results he expected, he claimed that the version he had tested was some other version and not the one he meant to test. This after he had posted pics showing that it was in fact the version in question. Then you both stopped posting in the thread. I wasn't hurt by that. I still laugh about it. It's an epic fail.

Let us see anyone quantify the drag from the dive flaps. Since we lack the required test information it should be interesting. I'm sure tests were done and HTC may have a copy but we don't. The UK Air Ministry in 1953, after reviewing all the data on dive flaps available to them, concluded that it was impossible to predict the effect of dive flaps throughout the flight regime because there were too many variables interacting, only flight testing can give conclusive results. So far we have information that there was drag and there was a pitch up when deployed after compression. The first time I saw this discussed here was Feb 2002. I think HTC is aware of all the issues, including drag.









Offline GScholz

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Re: P-38 dive flaps produce no drag
« Reply #88 on: March 20, 2014, 05:17:06 AM »
"With the first link, the chain is forged. The first speech censored, the first thought forbidden, the first freedom denied, chains us all irrevocably."

Offline Randy1

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Re: P-38 dive flaps produce no drag
« Reply #89 on: March 20, 2014, 06:19:19 AM »
I smell a dead horse.