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Kurfurst__
05-22-2004, 08:33 AM
I did a couple of dive tests recently, and it appears both the Mk V and Mk IX dive far too well compared to their real life reputation as being poor divers in combat, which is supported by every single real life account and comparison test I have seen .

Ie. the Mk V dives just as well as the 109F, and the MkIX have no problems outdiving the 109G... kinda strange.

Have not tested vs. US planes, well known for their outstanding dive capabilities, but wouldn`t be surprised if those couldn`t shake Spits off in a dive as they should and did when occasionally attacked by friendlies.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

Kurfurst__
05-22-2004, 08:33 AM
I did a couple of dive tests recently, and it appears both the Mk V and Mk IX dive far too well compared to their real life reputation as being poor divers in combat, which is supported by every single real life account and comparison test I have seen .

Ie. the Mk V dives just as well as the 109F, and the MkIX have no problems outdiving the 109G... kinda strange.

Have not tested vs. US planes, well known for their outstanding dive capabilities, but wouldn`t be surprised if those couldn`t shake Spits off in a dive as they should and did when occasionally attacked by friendlies.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

Tvrdi
05-22-2004, 09:00 AM
its not only with spits..it seams that almost all planes dives like bf109...thats why someone can catch u in a dive (in plane who were poor diver in WW2) when ur in Me109...

VW-IceFire
05-22-2004, 09:13 AM
All planes dive about the same in this game as many have found...

So lets point some fingers at all of the planes instead of just the Spitfires.

In addition to that, I've read that the Spitfire IX's dive ability was better than that of the Mark V and that it negated some (not all) of the FW190's advantage in diving out of combat. But thats a moot point considering virtually all dive about the same. You can still hold energy better in some planes over others on the flipside...so diving still has advantages.

http://home.cogeco.ca/~cczerneda/sigs/tmv-sig1.jpg
RCAF 412 Falcon Squadron - "Swift to Avenge"

Takata_
05-22-2004, 09:15 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kurfurst__:
I did a couple of dive tests recently, and it appears both the Mk V and Mk IX dive far too well compared to their real life reputation as being poor divers in combat, which is supported by every single real life account and comparison test I have seen .

Ie. the Mk V dives just as well as the 109F, and the MkIX have no problems outdiving the 109G... kinda strange.

Have not tested vs. US planes, well known for their outstanding dive capabilities, but wouldn`t be surprised if those couldn`t shake Spits off in a dive as they should and did when occasionally attacked by friendlies.
<HR></BLOCKQUOTE>

Just some questions about this dive problem.

- are you talking about :
Acceleration in dive ?
Maximum dive speed ?
Aircraft structural limit in dive speed ?
Controls and manoeuvrability in overspeed ?
etc.

Some points are simulated better than others, just tell us what you are thinking about, please.

Nub_322Sqn
05-22-2004, 09:39 AM
All planes dive too good Kurfwurst, known fact around here for some time now, for most people that is.

http://www.xs4all.nl/~rcma/banners/Nubarusbanner.jpg

VMF-214_HaVoK
05-22-2004, 10:01 AM
All planes seem to dive at same speed it is the speed limit that is different. It has also been mentioned that all planes have about the same zoom climb.

=S=

http://www.flightjournal.com/fj/images/hellcat_head_short.jpg

www.vmf-214.net (http://www.vmf-214.net)
(The Original BlackSheep Squadron of IL-2/FB/AEP/PF)

Kurfurst__
05-22-2004, 10:30 AM
The 'all planes dive the same' story is simply not true. Have no idea who invented it, but it can simply be checked, if you take a P-47 and a say, 109F up , and go in a full power 45 degree dive it WILL pick up speed faster than others. Simpliest way to check this is to lauch a QM at a given height, point the nose to same point so the dive angle is the same. You will notice that at the same altitudes, 3000m, 2500m, 2000m, the airspeed is rather different for the planes, by a margin of 30-40 km/h.

No, planes don`t dive the same. There aren`t lightspeed sized differences, but they differ quite a bit. Trouble is, the Spit, and maybe others, dive far too well.

Same goes to zoom climb.. if anybody says all zoom is the same, he probably never tested it. I did, and there`s MARKED difference of many hundred meters..


And of course I was talking about dive acceleration, the Spits pick up speed too quickly compared to others which are said to be faster accelerators in dive. There should be no reason for that.



http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

BigganD
05-22-2004, 11:26 AM
I think the CW spit turns to well at 7000+ with so small wings

"Get close .. when he fills the entire windscreen ... then you can't possibly miss." Erich Hartmann

k5054
05-22-2004, 11:35 AM
Kurfurst, if you have any real life dive data with comparisins, please post it. I'm under the impression that dive accelerations don't vary too much between a/c in real life at the beginning of a dive, say by 10-20% of the acceleration figure. How this builds up into a range extension/closure is not so clear. Certainly in the beginning, excess thrust/weight has a big part, later just gravity, the same for all, and later still gravity vs drag alone, allowing aircraft to be compared by the coefficient weight/flat plate area, the higher the better. On the diving thread I've listed this figure for 120 WW2 fighters. (The list has some errors because accurate input data is hard to find).
I've found some dive info on the NACA site, which I'm working on to refine my methods, but if anybody has dive comparisons in RL with entry conditions and time/distance data, please post it.

tazzers01
05-23-2004, 08:54 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BigganD:
I think the CW spit turns to well at 7000+ with so small wings

"Get close .. when he fills the entire windscreen ... then you can't possibly miss." Erich Hartmann
<HR></BLOCKQUOTE>

No mate. The clipped wing on the Spit increases speed (slightly), increases roll rate (significantly), increases the turn radius (fractionally) and increases stall speed (fractionally) otherwise it a plain old Spit.

Phil

Snuffy_Hadden
05-23-2004, 10:19 AM
I say make all the planes exactly alike each other. That way no one will have cause for whining about something.

Make all the guns all equal to each other too, no cause for complaint.

Then what will truely determine the quality of a dog fight will be the actual pilot.

http://ubbxforums.ubi.com/infopop/emoticons/icon_biggrin.gif

609IAP_Recon
05-23-2004, 10:38 AM
dive speed is close.

but above post on zoom - that is false - they are different.

this really hinders the p47 imo - not quick enough acceleration in a dive vs. light ac

Salute!

IV/JG51_Recon

http://www.forgottenskies.com/jg51sig2.jpg

k5054
05-23-2004, 10:40 AM
"I say make all the planes exactly alike each other. That way no one will have cause for whining about something.

Make all the guns all equal to each other too, no cause for complaint.

Then what will truely determine the quality of a dog fight will be the actual pilot"

..but the guys who fly void skins get an unfair advantage from the lack of heavy paint and draggy markings.

PzKpfw
05-23-2004, 01:19 PM
data from the 4th web site, on Spitfire dive performance:


Spitfire Maximum speeds in m.p.h I.A.S.
Diving (without external stores), corresponding to a Mach No. of -85:

Between S.L. and 20,000 ft. -450
20,000 and 25,000 ft. -430
25,000 and 30,000 ft. -390
30,000 and 35,000 ft. -340
Above .....35,000 ft. -310



Concerning 109 dive speeds:


The maximum permissible indicated airspeeds in the different heights are not being observed and are widely exceeded. On the basis of evidence which is now available the speed limitations ordered by teleprint message GL/6 No. 2428/41 of 10.6.41 are cancelled and replaced by the following data:

Up to 3 km (9,842 ft.) 750 km/h. (466 m.p.h.)
At 5 km (16,404 ft) 700 km/h. (435 m.p.h.)
At 7 km (22,965 ft) 575 km/h. (357 m.p.h.)
At 9 km (29,527 ft) 450 km/h. (280 m.p.h.)
At 11 km (36,089 ft) 400 km/h. (248 m.p.h.)


Regards, John Waters

---------
Notice: Spelling mistakes left in for people who need to correct others to make their life fulfilled.

----
The one that gets you is the one that you'll never see.
-----

----

"After 44 we called the new models the 'bumps', because every new model had another bump or hump on the fuselage, which naturally was particularly bad for the flight characteristics of the aircraft."

Walter Krupinski: on the Bf 109...
----

-----
"The damn Jerries have stuck their heads in the meatgrinder, and I've got hold of the handle."

Lt.Gen. George S. Patton, Jr. December 26, 1944.

------
"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. Febuary 1945.

------
For Americans war is almost all of the time a nuisance, and military skill is a luxury like Mah-Jongg. But when the issue is brought home to them, war becomes as important, for the necessary period, as business or sport. And it is hard to decide which is likely to be the more ominous for the Axis--an American decision that this is sport, or that it is business."
--D. W. Brogan, The American Character

[This message was edited by PzKpfw on Mon May 24 2004 at 09:52 PM.]

LuftLuver
05-23-2004, 01:24 PM
Amazing Kurfyisegrim, simply amazing.

You never seem to come up with any of these wonderful tests that show German a/c to be overdone in anyway. So from your whacked point of view, we can see that never in the history of IL2 has a German plane been overmodeled in any aspect.

β"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Άβ"Ά
"All your bases are belong to us."

Aaron_GT
05-23-2004, 01:29 PM
"this really hinders the p47 imo - not quick enough acceleration in a dive vs. light ac"

If entering a dive from cruise speed at planes with good excess power loading (typically lighter planes) should initially pick up speed faster than the P47, but the P47 will beat most in the end. Against the Fw190 it took 7000 feet for the P47 to pass the 190, so it might take a while. This will be true at medium or low altitudes at least, as the P47's power loading is mediocre compared to other planes at these altitudes. At higher altitudes the P47, due to its efficient turbosupercharging, actually has a power loading advantage.

Now if you just dropped a P47 and a 109 from 10,000 feet with the engine off, then the P47 would also initially outaccelerate the 109, but in reality the engine will come into play as well and complicate matters.

609IAP_Recon
05-23-2004, 01:33 PM
ah yes, thank you Aaron_GT.

Has anyone confirmed if FB supports this?

Salute!

IV/JG51_Recon

http://www.forgottenskies.com/jg51sig2.jpg

WWMaxGunz
05-24-2004, 12:05 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Kurfurst__:
The 'all planes dive the same' story is simply not true. Have no idea who invented it, but it can simply be checked, if you take a P-47 and a say, 109F up , and go in a full power 45 degree dive it WILL pick up speed faster than others. Simpliest way to check this is to lauch a QM at a given height, point the nose to same point so the dive angle is the same. You will notice that at the same altitudes, 3000m, 2500m, 2000m, the airspeed is rather different for the planes, by a margin of 30-40 km/h.

No, planes don`t dive the same. There aren`t lightspeed sized differences, but they differ quite a bit. Trouble is, the Spit, and maybe others, dive far too well.

Same goes to zoom climb.. if anybody says all zoom is the same, he probably never tested it. I did, and there`s MARKED difference of many hundred meters..


And of course I was talking about dive acceleration, the Spits pick up speed too quickly compared to others which are said to be faster accelerators in dive. There should be no reason for that.<HR></BLOCKQUOTE>


It does seem that something, maybe compression effect on prop drag or all drag I dunno, is not in the FM engine and it makes a bigger difference at high speeds and especially in really steep, near vertical dives. So people who look at them say that all dives are so. But dives where gravity force is not totally dominant seem to be more in line.

I guess you have data from Rechlin or somewhere on different 109 dive performances? And that ADFU test... there's a lot of room for interpretation but not as bad as pilot stories. You might as well share what you have though.


Neal

patch_adams
05-24-2004, 12:15 PM
This kurfust guy really knows what hes talking about it seems. ~S

ZG77_Nagual
05-24-2004, 12:29 PM
I have a question for Kurfurst - or anyone really - Do you think the k4 turns a bit too well at low speeds?

Kurfurst__
05-24-2004, 12:46 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by ZG77_Nagual:
I have a question for Kurfurst - or anyone really - Do you think the k4 turns a bit too well at low speeds?<HR></BLOCKQUOTE>

Have no real data, so I have no real idea.. http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif But, compared to others in 109 family, I thinks it reasonable. The stall comes at a bit higher speed than in the Gs, so it stall easier but the brutal engine output and the clean lines help it maintain airspeed in turns rather well. As I would expect... as compared to other planes (save the ones that are commonly accepted as overmodelled), vs. most I think its reasonable.The 109K was somewhat heavier than the others, ie. apprx. takeoff weights from memeory:

109 F-4 : 2900 kg
109 G-2 : 3050 kg
109 G-6 : 3150 kg
G-6/AS : about 3250 kg
G-14/U4 : 3300 kg
G-10/U4 : 3340 kg
K-4 : 3362 kg.

As can be seen, weight of 109s increased in very small increments with each version, hardly noticable from one plane to another.

109K is about 10% heavier than the 109G-2 only.. though I think the relation of manouveribility between F-4 and G-2 is sc*wed up. The Fs are far too bad, the G-2 is a bit too good IMHO. The very first Il-2 got it the best..

If engine outputs are modelled correctly with MAP/RPM... try the 109K at 100% throttle w/o MW50. Its about the same power as you have in G-2 or G-6... feels a lot different, isnt it? http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif Its manouveribility all about the sheer, brutal power of the DB 605D, but all except late soviet fighters followed the same path. Many of them a lot less successfully than the 109s.

http://www.x-plane.org/users/isegrim/fat-furred%20tigerB.jpg

"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".
- Lt. Gen. George S. Patton, Jr. Febuary 1945.

"One day a Tiger Royal got within 150 yards of my tanks and knocked me out. Five of our tanks opened up on him at ranges of 200 to 600 yards and got 5 or 6 hits on the front of the Tiger. They all just glanced off and the Tiger backed off and got away. If we had a tank like that Tiger, we would all be home today."
- Sgt. Clyde D. Brunson, US Army, Tank Commander, February 1945

BigganD
05-24-2004, 03:55 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by tazzers01:
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BigganD:
I think the CW spit turns to well at 7000+ with so small wings

"Get close .. when he fills the entire windscreen ... then you can't possibly miss." Erich Hartmann
<HR></BLOCKQUOTE>

No mate. The clipped wing on the Spit increases speed (slightly), increases roll rate (significantly), increases the turn radius (fractionally) and increases stall speed (fractionally) otherwise it a plain old Spit.

Phil<HR></BLOCKQUOTE> well..it is high alt, and you need longer wings to turn good, the cutwing turns to good at 6500+

"Get close .. when he fills the entire windscreen ... then you can't possibly miss." Erich Hartmann

PzKpfw
05-24-2004, 05:54 PM
Concerning Bf 109 weights its interesting to compare the Empty & normal loaded weights. Empty weight = without fuel, ammo, or pilot. Loaded = fuel, ammo & pilot.

Loaded weights in ( )'s I have not included max Take Off weights.


Bf 109E-3 - 4,189lbs (5,875lbs)
Bf 109F-1 - 4,330lbs (6,054lbs)
Bf 109G-1 - 4,968lbs (6,834lbs)
Bf 109G-6 - 6,834lbs (7,500lbs)
Bf 109G-10 - 5,880lbs (7,500lbs)
Bf 109K-4 - 6,000lbs (7,439lbs)

Regards, John Waters

---------
Notice: Spelling mistakes left in for people who need to correct others to make their life fulfilled.

----
The one that gets you is the one that you'll never see.
-----

----

"After 44 we called the new models the 'bumps', because every new model had another bump or hump on the fuselage, which naturally was particularly bad for the flight characteristics of the aircraft."

Walter Krupinski: on the Bf 109...
----

-----
"The damn Jerries have stuck their heads in the meatgrinder, and I've got hold of the handle."

Lt.Gen. George S. Patton, Jr. December 26, 1944.

------
"We've got the finest tanks in the world. We just love to see the German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. Febuary 1945.

------
For Americans war is almost all of the time a nuisance, and military skill is a luxury like Mah-Jongg. But when the issue is brought home to them, war becomes as important, for the necessary period, as business or sport. And it is hard to decide which is likely to be the more ominous for the Axis--an American decision that this is sport, or that it is business."
--D. W. Brogan, The American Character

ZG77_Nagual
05-24-2004, 06:10 PM
Thanks Kurfurst.
Based on all I've read I think she's a bit generous on the low end - I understand the motor pulling it around but in the stall regime I think it's a bit overmodeled. Offline the 109s seem to be the best AI - and flying against these in a p38 they will work very hard to stay with you in a slow turn - the k seems on a par with the other 109s which I think is not quite right. As I understand it the 109k was optimized for high speed and not as good a turn fighter as the earlier ones. Some pilot reports border on scathing in terms of maneuverability. It is very difficult to out stall fight a 109k in the p38. True to form though - they do climb very well. Oleg seems to have given the german AI a higher IQ than the rest http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif