Author Topic: Yak3 Drag modelling  (Read 24416 times)

Offline bustr

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Re: Yak3 Drag modelling
« Reply #90 on: May 30, 2019, 03:14:28 PM »
I was curious, Yak-3, spit16 and P47M.

The test started at 50ft on WEP if possible at the fastest speed. Flat turn left, record speed just before turn right, flat turn right record speed at end, barrel role, record speed at end into a vertical popup. Hang on prop and record alt and speed plane stalls off to aside.

100% fuel, full ammo load, WEP where possible 50ft level alt.


Yak-3
Max speed - 350
Left turn end speed - 332
Right turn end speed - 328
Barrel role end speed - 276
Popup stall alt - 2700ft
Stall speed - 90


Spit16 WEP
Max speed - 340
Left turn end speed - 320
Right turn end speed - 290
Barrel role end speed - 206
Popup stall alt - 2600ft
Stall speed - 90


P47M WEP
Max speed - 362
Left turn end speed - 332
Right turn end speed - 285
Barrel role end speed - 205
Popup stall alt - 2700
Stall speed - 85


Lazy comes to mind covering so many human aspects of this farce. I experience Fugi's whine all the time chasing spit16 and P47M and chances are by the time I run into them, they are a lot lighter from burning off fuel and ammo. I don't need to test the Yak-3 on half fuel, it's obvious what the outcome will be. Our Yak-3 is the monster the Russians say it was while our spit16 and P47M are the monsters the RAF and AAF said they were. Bunch of laziness going around.........
bustr - POTW 1st Wing


This is like the old joke that voters are harsher to their beer brewer if he has an outage, than their politicians after raising their taxes. Death and taxes are certain but, fun and sex is only now.

Offline Wiley

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Re: Yak3 Drag modelling
« Reply #91 on: May 30, 2019, 03:42:07 PM »
Just curious, looking at those numbers, is the Yak's end of barrel roll speed a typo?  Off the cuff if it was doing 70mph more than the others entering the zoom I would expect it to go a lot higher.

Wiley.
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Offline bustr

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Re: Yak3 Drag modelling
« Reply #92 on: May 30, 2019, 03:55:53 PM »
Are your hands broken??
bustr - POTW 1st Wing


This is like the old joke that voters are harsher to their beer brewer if he has an outage, than their politicians after raising their taxes. Death and taxes are certain but, fun and sex is only now.

Offline Shuffler

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Re: Yak3 Drag modelling
« Reply #93 on: May 30, 2019, 04:14:00 PM »
I was curious, Yak-3, spit16 and P47M.

The test started at 50ft on WEP if possible at the fastest speed. Flat turn left, record speed just before turn right, flat turn right record speed at end, barrel role, record speed at end into a vertical popup. Hang on prop and record alt and speed plane stalls off to aside.

100% fuel, full ammo load, WEP where possible 50ft level alt.


Yak-3
Max speed - 350
Left turn end speed - 332
Right turn end speed - 328
Barrel role end speed - 276
Popup stall alt - 2700ft
Stall speed - 90


Spit16 WEP
Max speed - 340
Left turn end speed - 320
Right turn end speed - 290
Barrel role end speed - 206
Popup stall alt - 2600ft
Stall speed - 90


P47M WEP
Max speed - 362
Left turn end speed - 332
Right turn end speed - 285
Barrel role end speed - 205
Popup stall alt - 2700
Stall speed - 85


Lazy comes to mind covering so many human aspects of this farce. I experience Fugi's whine all the time chasing spit16 and P47M and chances are by the time I run into them, they are a lot lighter from burning off fuel and ammo. I don't need to test the Yak-3 on half fuel, it's obvious what the outcome will be. Our Yak-3 is the monster the Russians say it was while our spit16 and P47M are the monsters the RAF and AAF said they were. Bunch of laziness going around.........

I agree... your chart was lazy in the fact you did not mention Time... stall speed to max speed.   You should be slapped with a dead trout.
80th FS "Headhunters"

S.A.P.P.- Secret Association Of P-38 Pilots (Lightning In A Bottle)

Offline Wiley

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Re: Yak3 Drag modelling
« Reply #94 on: May 30, 2019, 04:29:05 PM »
Are your hands broken??

Christ, dude.  I was just asking if it was a typo, as it seems out of whack.

If that's accurate, doesn't that mean it loses it's E in that zoom climb faster than the other two?

Wiley.
If you think you are having a 1v1 in the Main Arena, your SA has failed you.

JG11

Offline Devil 505

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Re: Yak3 Drag modelling
« Reply #95 on: May 30, 2019, 04:50:42 PM »
Are your hands broken??

Really? There's no need to be a dick over being asked a legitimate question. Not cool.


Also, it's "roll" not "role".  :aok
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Offline ACE

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Re: Yak3 Drag modelling
« Reply #96 on: May 30, 2019, 05:47:10 PM »
Christ, dude.  I was just asking if it was a typo, as it seems out of whack.

If that's accurate, doesn't that mean it loses it's E in that zoom climb faster than the other two?

Wiley.

He’s been a little uptight here lately Wiley. You’ll have to forgive him.
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Offline bustr

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Re: Yak3 Drag modelling
« Reply #97 on: May 30, 2019, 06:55:03 PM »
You gents are being lazy allowing others to do the work while you only use your keyboards, then being offended when you are asked for your work. Wiley is more than able to do the same test from A1 on NDilses if he has questions. This is like a government road crew where 11 guys sip coffee and one guy fills the potholes. Lord forbid they spot something they decide they need to tell the one guy working. Becasue he just has to address it while there is a pile of shovels next to the work area and get offended when he points to the shovels and asks "are your hands broken".

Well are your hands broken?
bustr - POTW 1st Wing


This is like the old joke that voters are harsher to their beer brewer if he has an outage, than their politicians after raising their taxes. Death and taxes are certain but, fun and sex is only now.

Offline atlau

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Re: Yak3 Drag modelling
« Reply #98 on: May 30, 2019, 07:36:25 PM »
Did someone kick your puppy?

Offline pembquist

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Re: Yak3 Drag modelling
« Reply #99 on: May 30, 2019, 08:57:05 PM »
Asking if it is a typo seems completely reasonable to me. It isn't questioning the results it is just clarifying whether there is a transcription error. There isn't much point in somebody repeating your experiment if they are comparing their results to mis-typed data. A simple "no" would be appreciated.
Pies not kicks.

Offline bangsbox

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Re: Yak3 Drag modelling
« Reply #100 on: June 05, 2019, 11:14:40 AM »
I think we are forgetting most of the sticks that fly the yak3 are nasty to begin with and very accurate. 


Offline atlau

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Re: Yak3 Drag modelling
« Reply #101 on: June 05, 2019, 11:53:04 AM »
I think we are forgetting most of the sticks that fly the yak3 are nasty to begin with and very accurate.

I find most of them very floppy and slippery :) like a pack of hyenas.

Offline drgondog

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Re: Yak3 Drag modelling
« Reply #102 on: June 11, 2019, 08:27:30 PM »
Curiosity compels me to ask: What is the source of validated wind tunnel data? Is there a CD vs RN plot and or algorithm to relate CD at computed speeds and ratios of RN at calculated speed to RNbase at Wind tunnel baseline? ie CD= CDo(RN/RNbase)^.x?
Do we have CD vs CL plots to assess pressure drag influence to baseline parasite drag? Are THP then calculated for each speed, altitude and GW as a function CD/CL for the new flight conditions?

Are the prop efficiencies built in, the carb intake pressure losses, the pressure drag of the airframe and wing immersed in the prop vortex, the exhaust thrust of in-line engines factored into THP available?

Probably not.
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Offline FLS

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Re: Yak3 Drag modelling
« Reply #103 on: June 12, 2019, 06:53:14 AM »
Assuming that all aero forces are handled the same way for all aircraft by the flight model seems like reasonable speculation.

Is there any reason to think the model efficiencies and limitations result in the Yak 3 getting an unfair advantage?

Is there any significant flight performance where the yak 3 does not match available data?

Those would be better starting points for discussion than the OP complaining about a plane he's not flying.

Offline icepac

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Re: Yak3 Drag modelling
« Reply #104 on: June 12, 2019, 07:55:10 AM »
A good yak9 pilot can can handle many yak3 pilots and then chase them down when they run.