Fulqrum Publishing Home   |   Register   |   Today Posts   |   Members   |   UserCP   |   Calendar   |   Search   |   FAQ

Go Back   Official Fulqrum Publishing forum > Fulqrum Publishing > IL-2 Sturmovik: Cliffs of Dover > Technical threads > FM/DM threads

FM/DM threads Everything about FM/DM in CoD

Reply
 
Thread Tools Display Modes
  #481  
Old 09-29-2012, 05:35 PM
Kurfürst Kurfürst is offline
Approved Member
 
Join Date: Oct 2007
Posts: 705
Default

Quote:
Originally Posted by Holtzauge View Post
Yes, I think the case for 500 Km/h SL speed for the Me109E is rather weak.
Well of course, since we have your toy excel sheet against thoroughly documented test data!
__________________
Il-2Bugtracker: Feature #200: Missing 100 octane subtypes of Bf 109E and Bf 110C http://www.il2bugtracker.com/issues/200
Il-2Bugtracker: Bug #415: Spitfire Mk I, Ia, and Mk II: Stability and Control http://www.il2bugtracker.com/issues/415

Kurfürst - Your resource site on Bf 109 performance! http://kurfurst.org
Reply With Quote
  #482  
Old 09-29-2012, 05:41 PM
TomcatViP TomcatViP is offline
Approved Member
 
Join Date: Aug 2010
Posts: 1,323
Default

Quote:
Originally Posted by Kurfürst View Post
What kind of difference do you have in mind?
I hve in mind the guns (barrel for sure). I think the rad were different. But I need to check this. There is also a good article on the net (in French probably) if you browse around "bf109" and switzerland ("Suisse"). Will try to have a look.

EDIT:
Guns for sure and prop

Last edited by TomcatViP; 09-29-2012 at 05:53 PM.
Reply With Quote
  #483  
Old 09-29-2012, 05:44 PM
Holtzauge Holtzauge is offline
Approved Member
 
Join Date: Jul 2011
Posts: 36
Default

Quote:
Originally Posted by TomcatViP View Post
I will be delighted to hve a look at your C++ "simulation". Pls show us the core engine instead of hijacking any scientific credits. Let me guess... inviscid, incompressible and lift line theo with linear curve discretisation? lol
Well you guessed wrong! I actually did a post a while back arguing for the introduction of subsonic drag rise which is missing in CloD but modelled in the C++ simulation. Modelled a Spitfire Mk1 and showed that the speed build up in CloD in quicker than it should be because compressibility effects are missing.

Seeing you seem to be such an expert perhaps you would be so kind to point out what is wrong in my Me109E speed/alt chart and how it really should look like?
Reply With Quote
  #484  
Old 09-29-2012, 05:51 PM
Kurfürst Kurfürst is offline
Approved Member
 
Join Date: Oct 2007
Posts: 705
Default

Quote:
Originally Posted by TomcatViP View Post
I hve in mind the gun barrel for sure. I think the rad were different. But I need to check this. There is also a good article on the net (in French probably) if you browse around "bf109" and switzerland ("Suisse"). Will try to have a look.
Yes I will check that, I had a good (IIRC German language) book about Swiss 109s, which helped me to ID J-347's WNr. and service record.

As for the gun barrels, I am not sure - one of the tests being waved about is explicitely about measuring the speed diff. between guns present/not present, and it's about 1 km/h.. I'd imagine different gun barrels amount to even less.

Rads look interesting though, this might account for something, but again, looking the Swiss test results, the difference is only about 8 kph at VDH, which from my experience, is an extremely good match for a serial production plane compared to the guaranteed specs!

Quote:
Originally Posted by Holtzauge View Post
Seeing you seem to be such an expert perhaps you would be so kind to point out what is wrong in my Me109E speed/alt chart and how it really should look like?
Well for one it probably has wrong data.. guessworked drag, guessworked wing effiencies, guessworked propeller effiency, manipulated until it fits one's agenda.

As Tagert said, garbage in... garbage out.

BTW, care to tell why you disappeared from allaboutwarafe forums? I am sure it's hell of a story.
__________________
Il-2Bugtracker: Feature #200: Missing 100 octane subtypes of Bf 109E and Bf 110C http://www.il2bugtracker.com/issues/200
Il-2Bugtracker: Bug #415: Spitfire Mk I, Ia, and Mk II: Stability and Control http://www.il2bugtracker.com/issues/415

Kurfürst - Your resource site on Bf 109 performance! http://kurfurst.org
Reply With Quote
  #485  
Old 09-29-2012, 06:08 PM
TomcatViP TomcatViP is offline
Approved Member
 
Join Date: Aug 2010
Posts: 1,323
Default

Quote:
Originally Posted by Holtzauge View Post
Well you guessed wrong! I actually did a post a while back arguing for the introduction of subsonic drag rise which is missing in CloD but modelled in the C++ simulation. Modelled a Spitfire Mk1 and showed that the speed build up in CloD in quicker than it should be because compressibility effects are missing.

Seeing you seem to be such an expert perhaps you would be so kind to point out what is wrong in my Me109E speed/alt chart and how it really should look like?
The core.. That's not too much to ask.
Reply With Quote
  #486  
Old 09-29-2012, 06:16 PM
Holtzauge Holtzauge is offline
Approved Member
 
Join Date: Jul 2011
Posts: 36
Default

Quote:
Originally Posted by Kurfürst View Post

Well for one it probably has wrong data.. guessworked drag, guessworked wing effiencies, guessworked propeller effiency, manipulated until it fits one's agenda.

As Tagert said, garbage in... garbage out.

BTW, care to tell why you disappeared from allaboutwarafe forums? I am sure it's hell of a story.
I think people are aware by your modus operandi by now: If you don't like the message then discredit the messenger.

Me "disappering" is for no more sinister reason than for working on a book project. Believe me it's much more satisfying than arguing about your doctored data or sparring with your mathematically challenged pal Crumpp!

So if my Me109E data is so totally wrong then I guess this means that HoHun's charts are off the wall as well because we get the same results, i.e. around 475 Km/h on the deck. Garbage in and garbage out in both cases huh?

BTW: Concerning disappering, in your case we know the answer don't we? Permanently banned from a number of forums and as editor in Wikipedia. That sure is one hell of a story!
Reply With Quote
  #487  
Old 09-29-2012, 06:20 PM
Holtzauge Holtzauge is offline
Approved Member
 
Join Date: Jul 2011
Posts: 36
Default

Quote:
Originally Posted by TomcatViP View Post
The core.. That's not too much to ask.
Actually it is. I'm going to use the C++ results in a book project so I'm not going to sink my own project by posting my code before that
Reply With Quote
  #488  
Old 09-29-2012, 06:39 PM
Kurfürst Kurfürst is offline
Approved Member
 
Join Date: Oct 2007
Posts: 705
Default

Quote:
Originally Posted by Holtzauge View Post
I think people are aware by your modus operandi by now: If you don't like the message then discredit the messenger.
Nobody needs to discredit you.

Quote:
Me "disappering" is for no more sinister reason than for working on a book project. Believe me it's much more satisfying than arguing about your doctored data or sparring with your mathematically challenged pal Crumpp!
.. but you seem to need to discredit others.

Quote:
So if my Me109E data is so totally wrong
It is. It doesn't match tested results, does it?
__________________
Il-2Bugtracker: Feature #200: Missing 100 octane subtypes of Bf 109E and Bf 110C http://www.il2bugtracker.com/issues/200
Il-2Bugtracker: Bug #415: Spitfire Mk I, Ia, and Mk II: Stability and Control http://www.il2bugtracker.com/issues/415

Kurfürst - Your resource site on Bf 109 performance! http://kurfurst.org
Reply With Quote
  #489  
Old 09-29-2012, 06:50 PM
Holtzauge Holtzauge is offline
Approved Member
 
Join Date: Jul 2011
Posts: 36
Default

Quote:
Originally Posted by Kurfürst View Post
It is. It doesn't match tested results, does it?
I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata or the caveted Messerschmitt marketing material with actual test results. The only test results I've seen point to 466-475 Km/h.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?
Reply With Quote
  #490  
Old 09-29-2012, 06:56 PM
Al Schlageter Al Schlageter is offline
Approved Member
 
Join Date: Oct 2007
Posts: 657
Default

Quote:
Originally Posted by Holtzauge View Post
I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata or the caveted Messerschmitt marketing material with actual test results. The only test results I've seen point to 466-475 Km/h.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?
And that is why we only see the V15 prototype data and not data for production Bf109Es.
Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 04:25 PM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright © 2007 Fulqrum Publishing. All rights reserved.