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XyZspineZyX
11-09-2003, 03:56 PM
Hi, pilots,

There are planes that hold in a dive much more than I think they should and planes that hold much less...are there any data known that Oleg uses to model speeds where planes break up?

Or is this rather crutial and important part of the sim left to somebody‚¬īs imagination?

XyZspineZyX
11-09-2003, 03:56 PM
Hi, pilots,

There are planes that hold in a dive much more than I think they should and planes that hold much less...are there any data known that Oleg uses to model speeds where planes break up?

Or is this rather crutial and important part of the sim left to somebody‚¬īs imagination?

XyZspineZyX
11-09-2003, 04:00 PM
Different for each plane surely?

S! Simon.
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XyZspineZyX
11-09-2003, 04:18 PM
It differs from patch to patch. Now the D-9 comes apart at 940km/h IAS, although I don't think it should break up at all. Never read any stories about 190's being teared up in high speed dives.

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XyZspineZyX
11-09-2003, 05:16 PM
robban75 wrote:
- It differs from patch to patch. Now the D-9 comes
- apart at 940km/h IAS, although I don't think it
- should break up at all. Never read any stories about
- 190's being teared up in high speed dives.


How many RL pilots would have dared dive one to 940km/h IAS?

S! Simon.
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Download the USAAF campaign folder here (http://mudmovers.com/Sims/FB/fb_essential_files.htm).

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XyZspineZyX
11-09-2003, 06:02 PM
P-51's lost their wings in highspeed dives, and it was a great diver. Bully Lang dived his Fw 190A-4 close to the speed of sound, and there was no damage to the airframe whatsoever. i don't know how Oleg models when planes come apart. I'm just curios why the P-51 should hold together for longer than an Fw 190. /i/smilies/16x16_smiley-happy.gif

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XyZspineZyX
11-09-2003, 06:04 PM
In real life most of the planes on the western front (including axis planes) didn't break up at all in dives. They simply entered the mach effect and lost control. The mach effect is when the air seperates from the trailing edge of the wing and control surfaces. It is basically a stall induced by too much speed that you really can't control. End result was diving straight into the dirt at 1000km/h or more. Some planes such as the Spitfire (I think, maybe it was Tempests) were used to explore the mach effect and could recover from transonic dives because the increased air resistance at lower altitudes would slow them down enough to recover. But even then some of the test planes were lost in the experiments.

So to answer your question, nearly all planes in FB are undermodeled in terms of break apart speeds. This is done intentionally to compensate for the lack of mach effect in FB. Maybe the upcoming BoB sim will feature this in its physics engine. But in FB I think we will just have to get along without mach effect.

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XyZspineZyX
11-09-2003, 06:09 PM
Extreme_One wrote:

- How many RL pilots would have dared dive one to
- 940km/h IAS?


Kurt Tank, Bully Lang, and Peter Crump for starters...


And no, I've never read anything about a FW190 coming apart in a dive, unlike *ahem* *cough* other aircraft I have read about...


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<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

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XyZspineZyX
11-09-2003, 07:43 PM
I'll just re-copy this here.

"The FW-190 (A-3) has a high rate of dive, the initial acceleration being excellent. The maximum speed so far obtained in a dive is 580 mph (934 km/h). True at 16,000 feet and at this speed the controls, although slightly heavier, are still remarkably light."


By my testing I had the 190A breaking apart at about 860 km/h true airspeed in FB 1.2beta, which is too low IMO.


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Message Edited on 11/09/0309:37PM by kyrule2

XyZspineZyX
11-09-2003, 09:06 PM
robban75 wrote:
- P-51's lost their wings in highspeed dives, and it
- was a great diver. Bully Lang dived his Fw 190A-4
- close to the speed of sound, and there was no damage
- to the airframe whatsoever. i don't know how Oleg
- models when planes come apart. I'm just curios why
- the P-51 should hold together for longer than an Fw
- 190. /i/smilies/16x16_smiley-happy.gif


Mustangs did not lose their wings in high speed dives. They sometimes experienced structural failure in high G pullouts.

The problem with the P-51 was that extremely high G pullouts from very high speed could be made with very little stick force.

That's one of the problems of having light stick forces at high speed.


And BTW, no FW-190 EVER got close to the speed of sound.

Regards,

SkyChimp

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XyZspineZyX
11-09-2003, 09:22 PM
Early P-51's had 6.0 lbs/g stick force, but by 42 this was 1.5lbs/g.. so 8g's took 12 lbs force.. not very much..



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XyZspineZyX
11-09-2003, 09:27 PM
SkyChimp wrote:
- Mustangs did not lose their wings in high speed
- dives. They sometimes experienced structural
- failure in high G pullouts.
-
- The problem with the P-51 was that extremely high G
- pullouts from very high speed could be made with
- very little stick force.

Ok, thanks for clearing that up!/i/smilies/16x16_smiley-happy.gif

- And BTW, no FW-190 EVER got close to the speed of
- sound.

Depending on what is considered close I guess. It was a phenomenal diver no doubt.

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XyZspineZyX
11-09-2003, 10:36 PM
The 190 was indeed a great diver with excellent construction. In 1.2beta the 190A breaks up too early IMHO. It starts shaking at around 750km/h and breaks up at around 860km/h. I just think this is too soon, especially when an RAF test pilot dove the 190A to 934km/h with no problems and with light controls.

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XyZspineZyX
11-09-2003, 10:58 PM
SkyChimp wrote:

- And BTW, no FW-190 EVER got close to the speed of
- sound.


Nothing with a prop in front of it did, although some of our more zealous US plane fans will claim the P-47 could do it/i/smilies/16x16_smiley-very-happy.gif

As far as the Mustang is concerned, it certainly never got close to the sound barrier either, in a dive or any other flight attitude.

Also, in a high-speed dive the Mustang certainly was NOT easy to execute a pull out and this is well documented in British tests, American experiences, and German fighter pilot observations.


<center><img src= "http://perso.wanadoo.fr/christophe.arribat/stoffwjabo.jpg" height=205 width=385>

<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

British Air Marshall, Sholto Douglas, 17 July 1942

XyZspineZyX
11-09-2003, 11:28 PM
Yea in FB P-51 could dive 1040 km/h and can pull up with easy. Have you any data about dive speed and controls any plane from FB?

XyZspineZyX
11-09-2003, 11:36 PM
FW190fan wrote:
-
-
- SkyChimp wrote:
-
-- And BTW, no FW-190 EVER got close to the speed of
-- sound.
-
-
- Nothing with a prop in front of it did, although
- some of our more zealous US plane fans will claim
- the P-47 could do it/i/smilies/16x16_smiley-very-happy.gif
-
- As far as the Mustang is concerned, it certainly
- never got close to the sound barrier either, in a
- dive or any other flight attitude.
-
- Also, in a high-speed dive the Mustang certainly was
- NOT easy to execute a pull out and this is well
- documented in British tests, American experiences,
- and German fighter pilot observations.


Any claims that planes reached or exceed the sound barrier were made before the effects of compressibility were fully known.



And as far as it being "not" being easy to pull a Mustang out of dive, it actually was. Too easy. That's why it was easy to exceed the ultimate-break G load placed on the P-51D of 9.6 Gs.

I doubt any plane, American or German, could sustain 9.6 Gs. But most were incapable of reaching it due to heavy stick forces, which the Mustang did not have.

See the stick forces someone posted above. Those numbers are correct.

Regards,

SkyChimp

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XyZspineZyX
11-09-2003, 11:58 PM
Kwiatos wrote:
- Yea in FB P-51 could dive 1040 km/h and can pull up
- with easy. Have you any data about dive speed and
- controls any plane from FB?


Here is what AHT says about the Mustang:

"A series of dive tests were made starting from 35,000 feet in a test airplane equipped with a mach meter. The idea was to explore the effects of compressibility such as buffeting, vibration, control force changes. Initial dives showed the onset of the problem occurred just under mach .75. Additional dives were made, using three test pilots, which carried the aircraft successively to mach .77, the .79 and on up to .81, and finally mach .83 (605 mph). As the dive Mach number increased the compressibility became more violent, but the aircraft was still controllable, and it was possible to fly out of the proble, when desired."

I don't think any plane in FB should be able to dive much beyond 900 km/h or so without experiencing buffetting, prorpising or instability. Dives to 1,000 km/h should be very rough. Much beyond that, planes should start loosing pieces.


Regards,

SkyChimp

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XyZspineZyX
11-10-2003, 12:06 AM
SkyChimp wrote:


- And as far as it being "not" being easy to pull a
- Mustang out of dive, it actually was. Too easy.
- That's why it was easy to exceed the ultimate-break
- G load placed on the P-51D of 9.6 Gs.


Of course not "normal" dives, I was refering to high mach number dives exceeding .71 mach. and above.

British tested Mustangs and Thunderbolts ran into some real problems above these speeds.



- I doubt any plane, American or German, could sustain
- 9.6 Gs.


Agreed.


<center><img src= "http://perso.wanadoo.fr/christophe.arribat/stoffwjabo.jpg" height=205 width=385>

<center>"We are now in a position of inferiority...There is no doubt in my mind, nor in the minds of my fighter pilots, that the FW190 is the best all-round fighter in the world today."

British Air Marshall, Sholto Douglas, 17 July 1942

XyZspineZyX
11-10-2003, 01:31 AM
Ok, if there was no breaking apart we could simulate this loss of controll by breaking apart, and the breaking point would be buffeting speed + 50km/h for every plane..

Now are there any tables awailable saying which plane buffeted at which speed?

So that we would be able to say:

Fw190A series is 100km/h slower for example

P51D 100km/h faster etc.

Does anyone have any tables or data for buffeting speeds of planes in WWII please?

XyZspineZyX
11-10-2003, 02:43 AM
AFAIK, there is no such chart. You just have to gleen whatever information you can from various sources.

Regards,

SkyChimp

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XyZspineZyX
11-10-2003, 05:48 PM
AFAIK Russian planes follow pilot's manuals:
LaGG-3 600km/h
La-5 620km/h
La-5FN 650km/h
Yak-3 650km/h
Here we are talking about IAS as stated in the manuals. Kozhedub said that he routinely dived La-7 and achieved speeds over 700km/h.

For german planes:
Bf-109G2 750km/h
Bf-109G6 750 km/h
Most probably IAS too but not stated in the manual.

I don't have manuals for other fighter planes. :-(

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XyZspineZyX
11-11-2003, 01:54 AM
Donthave any official data, try researching the Never Exceed Speed limitations of the plane your wondering about. If you go over the never exceed speed, in real life your wings fall off, making for a very bad day indeed.

XyZspineZyX
11-11-2003, 02:16 AM
robban75 wrote:
- It differs from patch to patch. Now the D-9 comes
- apart at 940km/h IAS, although I don't think it
- should break up at all. Never read any stories about
- 190's being teared up in high speed dives.
-

Surely sound barrier would be the limit for 190 as to any other prop plane. But there were tests of dives over 950kmh. (with 7G pull-up in german tests). Same results were obtained with 190A-7 and 190D-9. In US they test dived 190A-5 and in britain 190A-3 IIRC. Also 190A-4s were dived over 900kmh just after first delivery to JG 54.



Here's caption from The Best of the Breed
Airpower, July, 1976 Vol. 6 No. 4
by Col. "Kit" Carson

"FW-190A

A superb airplane, every inch a fighter. It could do a half roll at cruising speed in one second. Taking this in conjunction with the airplane's high top speed and rate of climb one expected its pilots to exploit its high speed qualities to the fullest without staying in there to "mix it up" in a low speed, flaps down full throttle, gut wrenching dog fight.

They did. The 190 pilots had a good airplane and some good advice. Nearly all of my encounters with the 190 were at high speeds. On at least two occasions when I met them, in my Mustang started porposing, which means I was into compressibility, probably around 550 mph. I don't know what my air speed indicator was reading, I wasn't watching it."

P-51 had lower critical mach number than 190 so it started to compress earlier.




Message Edited on 11/11/0301:31AM by ladoga

XyZspineZyX
11-11-2003, 02:23 AM
http://www.saunalahti.fi/meheko/190dive.jpg

XyZspineZyX
11-11-2003, 09:43 AM
yak3 breaks up at a little above 800kmph and the zero is wayyyyyy up there too,

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XyZspineZyX
11-11-2003, 09:57 AM
For the P-51, from my Pilot's Training Manual:


Maximum Allowable Indicated Airspeed at various alts

40,000 feet (12,192 meters)=
270MPH IAS 485 True(434.5 IAS KMH/ 780.5 KMH True)

35,000 feet (10,668 meters)=
305 MPH IAS 520 True (490.9 KMH IAS/ 836.9 True)

30,000 feet (9,144 meters)=
340 MPH IAS 545 True (547.2 KMH IAS/ 877.1 True)

25,000 feet (7,620 meters)=
385 MPH IAS 575 True (619.6 KMH IAS/ 925.4 True)

20,000 feet (6,096 meters)=
420 MPH IAS 590 True (679.9 KMH IAS/ 949.51 true)

15,000 feet (4,572 meters)=
465 MPH IAS 605 True (748.3 KMH IAS/ 973.7 True)

10,000 feet (3,048 meters)=
505 MPH IAS 605 True (812.7 KMH IAS/ 973.7 True)

These were lisited as the speeds at which onset of compressibility effects may occur and above which flight should not be attempted, but they are themselves "safe speeds". It also lists that the P-51 can exceed .75 Mach (75% the speed of sound) before encountering compressibility. Flutter effect is what could lead to loss of parts, and even wing failure, though once this happened in these aircraft you had already entered compressibility effects sufficiently that the flutter was not your only problem. The Control surfaces on the P-51 were sealed internally and as such stick forces were very light. With a very clean aerodynamic design, speed would build very quickly, and dive recovery could overstress any airframe of the time if G loads were allowed to exceed limitations by pilot over controlling(not hard to do at the speeds we are talking about, in an aircraft with relatively light stick forces at speed)


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Message Edited on 11/11/0301:09AM by TX-EcoDragon

XyZspineZyX
11-11-2003, 10:10 AM
robban75 wrote:
- It differs from patch to patch. Now the D-9 comes
- apart at 940km/h IAS, although I don't think it
- should break up at all. Never read any stories about
- 190's being teared up in high speed dives.


That's because most... if not all FW's could dive at their terminal velocity. Terminal velocity for the A-9 was somewhere in the mid 800's. You are right, the fact that they lose their wings is completely wrong.

If you want more information on this, talk to WUAF_Carbonfreeze. He has many many many books, links, and sources about FWs.

XyZspineZyX
11-11-2003, 03:04 PM
Well dont know how much in reality but in FBRC01 Mustang reaches 1030km/h IAS before braking up.

Tested it in offline mode, and I thoght P47 was the best diver in ww2http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

XyZspineZyX
11-11-2003, 04:18 PM
Extreme_One wrote:
speed dives.
-
-
- How many RL pilots would have dared dive one to
- 940km/h IAS?
-
- S! Simon.
- <center>

K.Tank f.i.

MfG Frank


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XyZspineZyX
11-12-2003, 09:03 PM
Take a look here gents, please:

http://forums.ubi.com/messages/message_view-topic.asp?name=Olegmaddoxreadyroom&id=ztwna

We did some research and found some interesting things.

XyZspineZyX
11-12-2003, 10:14 PM
Thank You for a US Campaign. I'm sure I'll enjoy it.

XyZspineZyX
11-12-2003, 11:02 PM
The zero dive speed can't be right. KI84 gets some insane dive speed too.