Author Topic: P47  (Read 1809 times)

Offline Fishu

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P47
« Reply #15 on: July 13, 2000, 09:23:00 AM »
Low drag on P-47 for sure...
I tested few of the AH planes gliding ability, and P-47 was real good at that.

109 was dropping over 4000fpm when trying to
keep speed at 150.

P47 was dropping 2800fpm when trying to keep speed at 150.

Fw190A5 was dropping 3700fpm when trying to keep speed at 150.

P51 was dropping 3900fpm when trying to keep speed at 150.

I dont know how typhoon or yak would had done this, but from my earlier experiences, those two definetly are between 3500 - +4000fpm if you want to keep speed at 150. (IAS) (have ran out of gas couple times, both drops like rocks after that, almost like 109)

If you go compare distances that P47 can glide compared to others, you'll find very much change on that.
P47 does also ski through the skies like a champion.

Oh.. got to tell this, I did climb 3000fpm in P47 at 20 to 27k with 200 IAS   (partly using wep, but not all the time)

Offline Toad

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P47
« Reply #16 on: July 13, 2000, 09:43:00 AM »
I seriously doubt that 150 was the "best glide" speed for all types.

Compare apples to apples. Find the "best glide" for each aircraft in RL and then try your test in AH-L. Prop drag is now a factor too, so make sure the prop is out for the glide.

I don't know how it will come out, but without knowing best glide and using it for each respective plane, that was a totally meaningless test.

[This message has been edited by Toad (edited 07-13-2000).]
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Offline Fishu

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P47
« Reply #17 on: July 13, 2000, 10:57:00 AM »
 
Quote
Originally posted by Toad:
I seriously doubt that 150 was the "best glide" speed for all types.

Compare apples to apples. Find the "best glide" for each aircraft in RL and then try your test in AH-L. Prop drag is now a factor too, so make sure the prop is out for the glide.

I don't know how it will come out, but without knowing best glide and using it for each respective plane, that was a totally meaningless test.

It was fast test, but it does show how those planes are affected by prop drag and stuff.

To make 109 faster, you need to pitch more down.. to pray it to keep in the air for longer, well.. it eats all the speed if you take nose above -4000fpm (and then you'll go -4000fpm did you want or not)

While P47 can glide 130-180mph if you wish to.

So, I'd say there is truth based factor in my quick testings that tells how others drops like rocks and P47 keeps in air like feather.
I can say that I don't really know how you can then optimize your gliding better with optimizing gliding speeds.

And this is not about gliding from 20k.
Though, still 109 and Yak drops like rocks from there if they suffer engine failure without someone shooting their engines off.
(lol, in that case that someone shoots your engine, you can glide as far as you wish!!!)

About prop drag.. 109 has small propeller as well as yak and P47 has alot bigger one, still I find 109 and yak prop drag far worst than P47s. (maybe p47 just has some electric windmill powerplant that generates electricity for some battery operated engine, hah)

It is that prop drag is too bad for other planes or P47 does not take a count on prop drag.

Offline niklas

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P47
« Reply #18 on: July 13, 2000, 11:38:00 AM »
Fishu youīre right, sink rate is a indicator of lift compared to drag at a certain speed

Propeller drag makes it a little bit more difficult. But i predicted it already 2 month ago that the Typhoon is the worst AC in the category E-retention. Without propeller drag, a good plane has a sink rate of ~-1600ft/min @5k  . P38 for example, or macchi205. A bad plane (at least it is modelled to be bad) like the 109 has ~-2000ft/min. And the worst (Typhoon) ~-2400ft/min.

Something is strange with propeller drag: When i glide and cut off my engine, at some planes the propeller keeps rotating - 109, P47, fw190 for example. At other planes (P38, mc205) the propeller stops to rotate. When the propeller stops, suddenly the sink rate improves to the values i had in earlier versions without modelling of propeller drag. Where the propeller keeps rotating, sink rate is a lot worse.

But why produce a standing propeller no drag at all? Shouldnīt it be inverse? A standing propeller produce imo more drag than a rotating propeller which "evades" the air??

Back to the P47, with propeller drag i had in 6k @160mph a sinkrate of -2800ft/min 100%fuel . The FW190A5, a plane with good wings too (yes!), has -3600ft/min. That means the P47 has at the moment superduper low induced drag wings!!

That remembers me to the earliest P38 in AH. Do you remember, with a sinkrate of -1300ft/min and very good E-retention and zoom??  Pyro, pls check your calculations for the P47, i think you did here a smiliar mistake!!

niklas

Offline Karnak

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P47
« Reply #19 on: July 13, 2000, 12:05:00 PM »
I think that AH considers the prop to be feathered when it is not spinning.  Thus the ac that have a stopped prop have reduced drag.  The spinning, upowered, nonfeathered prop does not produce significantly less drag than a stopped nonfeathered prop.

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Offline mx22

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P47
« Reply #20 on: July 13, 2000, 12:23:00 PM »
Just a question guys. How the hell do you make jug fly at 130???!!! Is it only me, but P47 is real pig with anything around 180 and stalls before way before 130.
I'll get home and make tests on gliding speeds, though I'm pretty sure I'll never get to anything close to 130mph.

mx22

Offline Fishu

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P47
« Reply #21 on: July 13, 2000, 12:44:00 PM »
 
Quote
Originally posted by mx22:
Just a question guys. How the hell do you make jug fly at 130???!!! Is it only me, but P47 is real pig with anything around 180 and stalls before way before 130.
I'll get home and make tests on gliding speeds, though I'm pretty sure I'll never get to anything close to 130mph.

mx22

I have no problem flying P47 with 130mph.. not at all. (I find more problem flying Fw190 with 130mph than P47)

Offline niklas

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P47
« Reply #22 on: July 14, 2000, 07:18:00 AM »
I did some tests, and all i can say now is that you canīt compare glide rates with the modelling of propeller drag.

But when the engine is out, propeller stands, prop drag disappears, so i found out a funny method to compare the P47 to the other AC: I started at A1 and just before i overshoot the mountain i pushed my stick forward and rammed my prop into the ground. Engine was out now, RPM gauge at zero, no prop drag  

The result: in 3k @ 160mph 100%fuel ~-1550ft/min (only a little bit better than a P38)
This is not uber or a mistake. But it is on of the best if not the best between all ac of AH and i didnīt expected that from a fighter with such a wing and so much surface area of the fuselage and such a huge frontal area.

btw, is there a ground effect modelled? ~30ft over the ground the glide rate improved suddenly.
 
niklas

[This message has been edited by niklas (edited 07-14-2000).]

Offline leonid

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P47
« Reply #23 on: July 14, 2000, 08:18:00 AM »
I am serious when I say the Yak has no trouble fighting P-47s.  I've engaged Jugs many times, a few times two at the same time, and at least one time against three.  The only time I was shot down by a Jug was when I was on the deck, slow, and shooting at somebody else.  While the Jug seems to scissors well at first, if you get it real slow, it cannot handle it, whereas the Yak handles low speed much better.

Hm, it's amazing how many people have trouble flying the Yak.  Maybe I should start filming my sorties ...
ingame: Raz

Offline mx22

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P47
« Reply #24 on: July 14, 2000, 08:40:00 AM »
Yak is a great plane, no doubts about it. Would have flown it myself, but I don't like its armament, plus it's very unstable.
Now I fly Jugs and I know that the only way for me to win a fight against Yak is to come from above on him, or do some fancy evasive manuever which will make Yak overshoot and give me a shot opportunity.

Offline niklas

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« Reply #25 on: July 14, 2000, 09:40:00 AM »
leonid, i only compared sustained turn rates, you know, brain out and pull pull pull  . I think you didnīt win your fights this way

niklas

Offline Ripsnort

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P47
« Reply #26 on: July 14, 2000, 09:53:00 AM »
Okay, I did some P47 and F4U tests, tell me why the P47 with the same engine as the F4u, can outclimb the F4U but the P47 has a heavier airframe?

[This message has been edited by Ripsnort (edited 07-14-2000).]

Offline F4UDOA

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P47
« Reply #27 on: July 14, 2000, 10:12:00 AM »
Ripsnort,

I have been asking that same question for a long time. The only thing I can tell you is that in head to head test with the
P-38, P-51B, F6F-5 and A6M-2/5 the F4U out climbed them all. But in AH it climbs like a dog. Take a look at this for your amusement.
 http://members.home.net/markw4/index2.html
Sound like the AH F4U-1D?
Take my advise, forget about the -1D. Fly the -1C, it is based on the -1A model and climbs better in AH than the -1D. Also turns and handles better at low speed. I have no trouble with P-47's in AH except when they have alt. Just look at the F4U-4 compared to the -1D. It had 200Hp more and climbed at
4000fpm. Over 1K better than the -1D and it weighed more. No A/C I have ever heard of has been able to do that with such a small change in power rating. I had a bet on that with HT going back to the Beta day's. I think he chose to forget. I have some physics calcs on the subject I can share with you that would also seems to disagree with the current FM. Sorry to rant, I have given up my pursuit of this issue for a while since Pyro said he would check a couple of things.

<S> Ripsnort, let me know when your squad is ready. I may come visit.

Later
F4UDOA

Offline Dinger

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P47
« Reply #28 on: July 14, 2000, 10:27:00 AM »
Hmm... Would people have trouble with the yak because it only has one cannon and limited ammo?

Offline Westy

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P47
« Reply #29 on: July 14, 2000, 12:09:00 PM »

They're vastly different aircraft? The propellor too?

-Westy