On Soviet turning time tests. Comments Please

[VG-33]

Hello,

06-20-2009, 11:09 PM
#74

Soren
Posts: 5,763 Sorry but you're the one using ridiculous Clmax figures VG-33, not me.

Or are you to suggest that you know more than the guys at the National Advisory Committee for Aeronautics??

Also I suggest you leave this argument until you start accepting the reality of things

Well, obviously you disagree -dislike in fact- with my real trials based flight model. I admit, may i made some mistakes...

06-15-2009, 04:55 AM #13

Soren
Senior Member

Like I've said before I'd take the Soviet data above with a large handful salt. But that's just my advice to you guys, you are free to believe in what you want ofcourse. I will however note that the Hurricance was in general considered a better turnfighter than both the Spitfire Bf-109.

If you want to know the true turn performance of these fighter aircraft then I suggest you take a look at the physics, in my experience it never lies, ever.
__________________

If you 're such a scientist, will you show your own models of mecanics of flight, instead of pollute us with idiomatic assessments and hollow sentences.
But you aren't to good on physics aren't you? You speak a lot obout it and surprisingly never use it...

So I suggest you, to show us how fluent you are in physics in order to support your arguments. Or leave definitly all reference to that science, since you don't know what you're talking about, as for soviet, finish or british ToT trials.

Regards

VG-33

 

[Soren]

You're the one who doesn't know what you're talking about VG-33, not me.

I can show you the physics no problem, which part are you looking for ? The interesting thing though is that it's very simple really, cause the a/c with the highest amount of lift power pr. amount of weight, and an acceptable amount of drag, will turn the best. That's simple physics for you, now are you gonna try and deny it ? Good luck!

Here's some of the formulas you'll need.

L = Lift = Cl * A * .5 * r * V^2
D = Drag = Cd * A * .5 * r * V^2
Cl = Lift Coefficient = L / (A * .5 * r * V^2)
Cdi = Induced drag = (Cl^2) / (pi * AR * e)
Cd0 = Zero lift drag coefficient (Determined experimentally)
Cd = drag coefficient = Cd = Cdo + Cdi = D / (A * .5 * r * V^2)


Use them and you can determine the amount G forces an a/c can pull at specific speeds, the stall speed, the L/D ratio etc etc...

 

[VG-33]

You're the one who doesn't know what you're talking about VG-33, not me.

I can show you the physics no problem, which part are you looking for ? The interesting thing though is that it's very simple really, cause the a/c with the highest amount of lift power pr. amount of weight, and an acceptable amount of drag, will turn the best.

Oh! no...You see that! Did you find it alone by yourself, or daddy helped?
No seriously, stop taking the others for idiots and get going in more advanced calculations.

That's simple physics for you, now are you gonna try and deny it ? Good luck!

Here's some of the formulas you'll need.

Thank you, but i have already used them previously as you can see in my posts.

06-19-2009, 09:09 PM #71
VG-33
Member


Quote:
BTW - Thanks for the turn test data -....
No problem. For 73,8%, n(y) = 3.6g; n(z) = 1; n(t) = 3.736


n(t).m.g = 1/2 .(rhô) .V².S.Cz

Cz*= 2mg/(rhô) V²S

Cz = 2 x 3.73 x 1700 x 9.81 / ( 0.971x 1.225) ** x 70² x 22.15

Cz = 124 410,4 / 131 139,5

Cz = 0.95***

Ok? more?

06-20-2009, 11:06 PM #73
VG-33
Member


Join Date: Jun 2009
Posts: 45 Quote:
Originally Posted by Soren

Now regarding the Clmax of the P-51, I would agree on ~1.5, eventhough I remember NACA saying 1.35 (Report 829). By comparison the Spitfire's was 1.36, Bf-109F/G/K was 1.7 and FW-190's was 1.61. All three a/c also have lower landing stall speeds, the Spitfire Bf-109 considerably so, and the Fw-190 being very close and pretty much the same as the P-51.

So my assessment has largely derived from the standpoint of lift generated vs the weight of the aircraft plus the amount of power available.

.

Your assessments will be less ridiculous the day you would use realistic Cl values.

So on ToT(mini):

P-51's Cl = 1.095

Spit's Cl = 1.08- 1.14

Me 109 G2 Cl = 1.1-1.15

FW 190 Cl = 1.44

Is it enough, or do you want more?

L = Lift = Cl * A * .5 * r * V^2
D = Drag = Cd * A * .5 * r * V^2
Cl = Lift Coefficient = L / (A * .5 * r * V^2)
Cdi = Induced drag = (Cl^2) / (pi * AR * e)
Cd0 = Zero lift drag coefficient (Determined experimentally)
Cd = drag coefficient = Cd = Cdo + Cdi = D / (A * .5 * r * V^2)

Use them and you can determine the amount G forces an a/c can pull at specific speeds, the stall speed, the L/D ratio etc etc...

IT's your turn to use them as you just said now, so apply your famous forulas in order to establish the best climb , the best sustainted turn and radius of a Me-109, a Spit, or a La-5...at 1000m or SL for instance.

I'm waiting 8)

Regards, VG-33

 

[Soren]

Oh! no...You see that! Did you find it alone by yourself, or daddy helped?
No seriously, stop taking the others for idiots and get going in more advanced calculations.

No, but considering your inability to acknowledge the simple importance of weight, lift power you might wanna contact someone of your own to help you out. But don't expect any help if you behave as obnoxiously towards them as you have towards me, then their willingness to help will no doubt be limited.

IT's your turn to use them as you just said now, so apply your famous forulas in order to establish the best climb , the best sustainted turn and radius of a Me-109, a Spit, or a La-5...at 1000m or SL for instance.

I'm waiting

My turn ? Ok, no problem. But when is it gonna be yours then cause I'd certainly like to see some worthwhile stuff from you as-well, esp. since so far you've only posted complete bollocks.

Anyway on with the physics!

Lets take the Bf-109F-4 for a spin:

Bf-109 F-4 specifications:

Weight: 2,890 kg
Wing area: 16.15 m^2
Wing span: 9.92 m
Wing AR: 6.09
Wing Clmax: 1.70
Cd0: 0.023

Engine power: 1,325 HP at 1.42 ata

And the methods for calculating drag lift, all of which can be used to determine G loads, L/D ratios stalling speeds etc etc:

Lift (L) = Cl * A * .5 * r * V^2

Coefficient of lift (Cl) = Established in windtunnel tests

Drag (D) = Cd * A * .5 * r * V^2

Drag Coefficient (Cd) = Cd0 + Cdi

Induced drag coefficient (Cdi) = (Cl^2) / (pi * AR * e)

Coefficient of drag at zero lift (Cd0) = Established in windtunnel tests

Note: End results are in Newtons (N), so you'll have to convert into Kilogram force (Kgf).

1 Newton = 0.1019716213 Kgf

Methods for calculating turn radius:

Radius = (V^2) / (g * √[n^2 - 1])

Radius(min) = (Vstall^2 / g) * (n / √[n^2 - 1])

Vstall = Aerodynamic stall speed for the aircraft in question.
g = gravitational constant (i.e. 9.82 m/sec^2)
n = steady-state maneuver load factor (i.e. maximum amount of g's you can pull)

Methods for calculating 360 degree turning time and the turn rate

360 deg turn time = 2 * pi * r / V

360 deg turn time = 2 * pi * radius / velocity

The turn rate in degrees per second is then found by dividing 360 by the time:

Rate of Turn = 360 / time
_____________________________________________

So now we atleast know the basics. Now do you want me to demonstrate why the Bf-109 F-4 turns better than the P-40 VG-33, or can you do the math yourself ? I'm very curious to see you demonstrate how the P-40 is ever gonna turn better knowing that it's Clmax is 1.45 and the Cd0 is around 0.028 to 0.03.

 

[VG-33]

to acknowledge the simple importance of weight, lift power


Anyway on with the physics!

Lets take the Bf-109F-4 for a spin:

Bf-109 F-4 specifications:

Weight: 2,890 kg
Wing area: 16.15 m^2
Wing span: 9.92 m
Wing AR: 6.09
Wing Clmax: 1.70
Cd0: 0.023

Engine power: 1,325 HP at 1.42 ata

OK. Apply this data in order to build a flight model, for climb, turn rate, radius...A have already done mine, so make your realistic proposal!

And the methods for calculating drag lift, all of which can be used to determine G loads, L/D ratios stalling speeds etc etc: and Methods for calculating turn radius etc:...

I never asked you for that, obviously you don't pay the bandpass to fullfil it with your flood that way...
So come on, spit it on now!

VG-33

 

[Soren]

VG-33 I'm sorry but you haven't provided anything, so until you do please stop claiming you have.

 

[VG-33]

VG-33 I'm sorry but you haven't provided anything, so until you do please stop claiming you have.

You are a kind of idiot or what? The deal is clear:

I provide you [/B ]my assesments of rates of turn , rate of climb, radiuses from soviet ( you also have british, finish) trials.

You desagree with them. OK, why not... So give us the real numbers, from your "german"documents or your own calculations.

 

[Soren]

VG-33, you're digging own grave at this point.

You seem determined to ignore the fact that the Finnish never tested the 109 F-4, and the fact that neither the Soviets or the Finnish ever flew their a/c at 1.42 ata.

Furthermore you have clearly demonstrated that you're completely unaware of the fact that the smallest radius of turn and highest turn rate is achieved when flying at Clmax. And the ability then to hold the speed in the highest performance turn is determined by the amount of drag the airframe creates as-well as the power available.

Now I've already given you the tools to calculate the turn radius turn rate of both a/c, you on the other hand have provided nothing, you haven't even yourself attempted to calculate turn radius or rate for crying out loud! So how about you do the math so you can see for yourself that the Bf-109 featured both a better turn radius and rate.

In short all you have done so far VG-33 is ridiculing yourself and demonstrated your lack of knowledge on the subject, nothing else. Your ridicously simple little calculation based on Finnish trials is worthless.

 

[Juha]

Hello Soren
in fact Finns flew 109Gs with 1,42 ata, and if you look Soviet tables on G-2, they gave its engine power as 1475 hp, and you should know what that means.

Juha

 

[Strawn]

I would love to run the math on this, but there seems to be some missing information. Like G-loading maximums.

I've 'danced' with these equations, and a few more, for months now to meet a performance modeling requirement for gaming. I've reviewed this forum for insite toward the task, and have 'amused' myself at the constant 'tone' of some of the 'players', with the following (albeit unsolicited) observations/questions:

Soren, can you submit information, advice, or the like without implying that all who disagree with you are idiots, or ignorant savages? Are you able to comment constructively?

There is an obvious difference between the presentations of taking the Soviet information 'with a grain of salt' versus 'the Soviet information is at variance with my sources'.

Failing that, at least, thanks for the 'amusement'.

 

[VG-33]

Furthermore you have clearly demonstrated that you're completely unaware of the fact that the smallest radius of turn and highest turn rate is achieved when flying at Clmax.

Ok, i might have done some mistakes, nobody's perfect. I will try to do the calculations for Me-109F with your values, by my side.
And for best climb rate? Should i take your Clmax = 1.7 too?

Now I've already given you the tools to calculate the turn radius turn rate of both a/c,

For this time, and the other ones, don't give me things i don't need and/or already have...So about your tools, why don't you use them, instead of giving them to the others?

you on the other hand have provided nothing, you haven't even yourself attempted to calculate turn radius or rate for crying out loud!

But i need some more elements, should i take a NACA 2R1, 2312 or 2412 wing profile?

So how about you do the math so you can see for yourself that the Bf-109 featured both a better turn radius and rate.

Listen, you shout loud first that soviet, british, finish test were false or erroneous. So prove it!

In short all you have done so far VG-33 is ridiculing yourself and demonstrated your lack of knowledge on the subject, nothing else. Your ridicously simple little calculation based on Finnish trials is worthless.

A least, i did some simple calculations on I-15, 109G2, SpitIX... You, did nothing, except flooding and breeding as hell. I suppose even simple calculations are far above your geat intellectual abilities?
So even if you're not able to caclulate anything, ask to daddy Ho Hun for real german ToT trials or propose your own assesments, and we will work on it, ok?

VG

 

[Soren]

This is getting out of hand, I've tried being polite towards you VG-33 but you've refused to have an adult conversation on the matter at hand. You're a very childish and abusive person, and sadly you haven't got a clue what you're talking about.

You want the figures to work with? I can give them to you, I can even give you the formulas in which you need to apply them. It will however not matter since you seem unable to grasp even the very simplest of rules within aerodynamics.

Bf-109 F-4:
Weight: 2,890 kg
Wing area: 16.15 m^2
Wing AR: 6.09
Clmax = 1.70
Cd0 = 0.023
Power = 1,325 hp

P-40E:
Weight: 3,760 kg
Wing area: 21.92 m^2
Wing AR: 5.9
Clmax = 1.45
Cd0 = ~0.028
Power= 1,150 hp

That's all the data you'll need. Now work with it. It doesn't take a genius to figure out that the Bf-109 is the better turner.

If you haven't posted anything worthwile in your next post then I'll do the calculations for everybody to see.

 

[claidemore]

Soren: Clean fighter weight of a P40E is actually 3847 kgs.
The 109F4 dattenblat from 1942 shows 2900kgs, would that not be the weight of the 109F4s cleared for 1.42 ata? That report also lists the wing area as 16.10 sq/m.

If you are using 1325 hp for the 109,(Start u. Notl.) then shouldn't you use WEP of 1470hp for the P40E? We are talking about pouring on the coal for max turn in a fight. I'm sure the Soviets didn't 'baby' the engine when they were testing it.

 

[VG-33]

This is getting out of hand, I've tried being polite towards you VG-33

It's very impolite to do not answer to the questions

I will try to do the calculations for Me-109F with your values, by my side.
And for best climb rate? Should i take your Clmax = 1.7 too?

But i need some more elements, should i take a NACA 2R1, 2312 or 2412 wing profile?

but you've refused to have ...

... in your next post then I'll do the calculations for everybody to see.

Yes thak you...let's everybody see.

VG-33

 

[Soren]

The wing area is 16.15 m^2 according to most documents Claidemore, not that it's going to make any difference however. The weight is exactly 2,890 kg, so it was probably rounded up to 2,900 in some documents, though I can't understand why you'd care about 10 kg ?

As for the P-40;

We can put in the 1,470 hp, cause yes, in a max performance turn you're gonna wanna squeeze every bit of jiuce outta that engine of yours!

So the power loadings of both a/c is:
Bf-109F-4 = 2.18 kg/hp
P-40E = 2.63 kg/hp

As you can see, it's not looking good for the P-40, esp. not considering the much lower drag of the Bf-109.

Knowing the max lift coefficient of both a/c we can here also see the exact amount of G's both a/c can pull at specific speeds at SL:

Lift equation (Bf-109):

CL * A * .5 * r * V^2 = X Newtons

1.7 * 16.15 * .5 * 1.225 * 112^2 = 210942.256 N

Convert result in Newtons into kgf:

210942.256 Newtons = 21510.123845 kgf

Divide result with a/c weight to get Max G:

21510.123845 / 2890 = 7.44

Max G at 112 m/s (400 km/h):

7.44 G
_______________________________________

Lift equation (P-40E):

CL * A * .5 * r * V^2 = X Newtons

1.45 * 21.92 * .5 * 1.225 * 112^2 = 244202.829 N

Convert result in Newtons into kgf:

244202.829 Newtons = 24901.758399 kgf

Divide result with a/c weight to get Max G:

24901.758399 / 3870 = 6.43

Max G at 112 m/s (400 km/h):

6.43 G
______________________________________

Combine the above with the fact that Bf-109 featured a lot less drag than the P-40 and it becomes quite clear that the Bf-109 was a more capable a/c in the horizontal than the P-40.

 

[Soren]

VG-33 let me remind you that you have NOT provided the following:
1.) Formula for or Calculations of turn radius
2.) Formula for or Calculations of turn rate
3.) Formula for or Calculations of stall speed
4.) Formula for or Calculations of accessable G forces at specific speeds

I on the other hand have already provided all of the above, so how about you provide just ONE, esp. before you start claiming you have provided them all? So far you've done exactly squat VG-33, and your childish behavior hasn't helped you one bit either except for making you look completely ignorant and foolish.

It's time to cut your losses and leave the matter now VG-33..

 

[VG-33]

VG-33 let me remind you that you have NOT provided the following:
1.) Formula for or Calculations of turn radius
2.) Formula for or Calculations of turn rate
3.) Formula for or Calculations of stall speed
4.) Formula for or Calculations of accessable G forces at specific speeds

I on the other hand have already provided all of the above, so how about you provide just ONE, esp. before you start claiming you have provided them all? So far you've done exactly squat VG-33, and your childish behavior hasn't helped you one bit either except for making you look completely ignorant and foolish.

It's time to cut your losses and leave the matter now VG-33..

1) We don't need your opinion
2) Provide formulas, what for? I can give you all formulas you want but you won't be able to use them, as an ignorant you are...

And remember : It's very impolite to do not answer to the questions

I will try to do the calculations for Me-109F with your values, by my side.
And for best climb rate? Should i take your Clmax = 1.7 too?

But i need some more elements, should i take a NACA 2R1, 2312 or 2412 wing profile?

Will you answer to my questions someday or not?

 

[Soren]

Where do these people come from..

 

[Juha]

Hello
I updated my list again according to the new info provided by VG-33 and Kurfürst and from Gordon's and Komissarov's book on US a/c in the SU.
Many thanks to Claidemore, Kurfürst and specially to VG-33
Juha

Soviet tests were flown at 1000m. When time of turn is given xx – yy sec, they are different times for turning in left or right.

Polikarpov I 15 serial: 8 - 8.5

Polikarpov I-15bis: 10,5

I-153 (1939) "Gukll"
- 11,4 - 12,4 sec (Finnish tests 12 sec, radius 110m, maybe the most feared opponent to Fokker D. XXI pilots during Winter War, FAF used war booty I-153s as a frontline a/c to autumn 44, during later part of the Continuation War (25 Jun 41 – 4 Sept 44) as recon fighter, last kill on 29 July 44, a P-39 from 773 IAP)

I-16 type 29 (1940)
- 16-19

Yak-1M
- 17

Yak-9 (1943)
- 17 or 17 - 18 sec (Finns thought that Yak-9 was very manoeuvrable, there are many comments like that in the FAF 109G pilots' combat reports)

Hurricane IIA
- 17-18 (original armament)

Spitfire F Mk IX
- 17,5 sec

P-40C
- 18,0s mid. at 3290 kg in 10/1941

Yak-1 (1943)
- 18

P-39D-2 (with wing armament)
- 17,7-18,7 sec

Spitfire LF Mk IX (Merlin 66)
- 18,5sec

Spitfire Mk VB
- 18,8 sec

LaGG-3 series 28 (1942)
- 19 (Finnish tests for war booty LaGG-3 series 4 (LG-1) with wings mod with slots: 23s with 40km/h speed loss, the same plane shot down a Soviet LaGG-3 from 415 IAP on 16 Feb 44 after fairly long turning fight, the fight began as an head on meeting with 2 escorting LaGG-3s against the LG-1. After a while after an head on pass one of the Soviet LaGGs disengaged but the second continued the turning fight until it was hit after which it tried disengage but the FAF pilot followed and shot it down. So Finns were not altogether hopeless in flying early LaGG-3s, there were some other contacts with FAF and Soviet LaGG-3s which ended without losses on either side. IMHO in early 44 Soviet LaGG-3s should have been at least series 28 or later. Finns concluded that LaGG-3 turned more or less as well as 109G. When Finns tested LaGG-3 against Hawk 75A, LeLv 32 (Fighter Squadron/Jagd Gruppe) used both in combat, conclusion was that if at the beginning LaGG-3 was behind Hawk 75A after only 1½ turns situation was reversed.)

LaGG-3 series 66 (1943)
- 19 (this lightened version was IMHO better than series 28, a LW top ace, IIRC Barkhorn, told later that hardest fight he ever fought was a long duel against a LaGG-3 from a GIAP in 1943/44, which ended when both disengaged simultaneously, so late over the Southern sector IMHO the LaGG must have been the lightened series 66 a/c.)


La-5FN (1943)
- 18 – 19 or 19 (Finns thought that La-5F/FN was a bit better turner than 109G at low level. It was also the most dangerous opponent of FAF 109Gs during the heavy fighting in summer 44, even if one cannot find so many glowing appraisal of La-5 than of Yak-9 in FAF 109G pilots' combat reports )

P-40E
- 19,2s mid. at 3840 kg in 07/1942

Hurricane IIA
- 19-20 sec (Soviet 91 oct fuel 4x20mm ShVAK)

La-5F (1943)
- 19-20 (Finns thought that La-5F/FN was a bit better turner than 109G at low level, high back La-5, which Finns called LaGG-5, was more or less equal to 109G-2 in low-speed turning fight at low level)

Yak-7B
- 19-20 (Finns misidentified some Yak-7Bs as Spitfires, they were told that they might met Spitfires, and thought that they didn't live up their high reputation)

Yak-7B (1943)
- 19-23

Yak-9D
- 19-20

Yak-9M
- 19-20

Yak 1 (1942 Winter variant)
- 19.5 sec (heavier due to insulation, heating ducts etc)

Me 109F-4
- 19,6 ( sometimes 19,8 ) -20.5 NII (Soviet max speed for the ac on slow side, so probably the plane had some problems)

P-39Q-15, without gunpods.
- 20-21sec (From 3./HLeLv 34 report on actions during the hectic summer 44. "AC (P-39) is more or less as good as La-5 (at this stage means La-5Fs and FNs) but maybe less manoeuvrable.")


Me 109G-2
- >20-21,5 middle 21 NII (Finnish tests, also at 1000m, 1,3 ata, sustained 22 sec, speed 360 km/h 3G)

Yak-1 (1942)
- 21

LaGG-3-37
- 22 sec (Armed with a 37mm NS-37 cannon and 1x12,7mm UB hmg. Also had LE slats. Finns met these a/c in summer 44, one regiment equipped with these and Yak-9s was transferred from VVS Black Sea Fleet to VVS Baltic Fleet to reinforce Soviet attack forces, but I recall only comments on their good tactics and unusual camo from combat reports.)

FW 190A-4
- 22 - 23 sec

Me 109G-2/R6
-22,6 sec

Mustang Mk I (Soviet tested one of these (AG348 ) and speed at 4600m (587km/h), the designation used in some Soviet docus, NA-73, and V1710-F3R engine. So not P-51A but XP-51 in USAAF parlance)
- 23 sec, weight 3884kg

FW-190 A4 turn rate is
- 23-24s LII-NKAP
- 22-23s NII-VVS


109E-3
- 23-26sec with 1.33 ata, max 5 min power setting

MiG-3 (1942)
- 23 (Finns: at lower level not very manoeuvrable in horizontal plane)

P-47D-10-RE, engine R-2800-63
- 26 sec 30 sec depending on source.

P-47 in 1945
27-28sec

109E-3
- 26,5-29sec at 1.26 ata (The supercharger seemed to have malfunctioned at low level, which was very important for these tests made at 1000m. German specs give 18.92 sec for a sustained turn at SL for the Emil, at 5 min rating, w/o using the 1-min special low-alt augmented rating.)

 

[Juha]

Hello Soren
How your calculations take into account the observation made by the Finnish test pilot:" One cannot pull 109G-2 into too tight turn before speed drops under 350km/h when not using full power." That because the heaviness of the elevators. Of course higher one went less effect the heaviness had to turn time but we are now talking on Soviet tests which were made at 1000m.

Juha