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sightreader
07-07-2007, 10:53 PM
Howdy all!

I'm doing a game about the old "canvas" days of dogfighting, and I was wondering if any have good book references on the performance of World War I recon and bomber aircraft? I'm looking for data beyond just ceiling and top speed... some more subjective data like manuverablility, roll rate, energy bleed, reliability and so forth.

Hey, by the way... what does VVS stand for, anyway?

sightreader
07-07-2007, 10:53 PM
Howdy all!

I'm doing a game about the old "canvas" days of dogfighting, and I was wondering if any have good book references on the performance of World War I recon and bomber aircraft? I'm looking for data beyond just ceiling and top speed... some more subjective data like manuverablility, roll rate, energy bleed, reliability and so forth.

Hey, by the way... what does VVS stand for, anyway?

Cajun76
07-07-2007, 10:57 PM
VVS Voenno-Vosdushniye Sili (Soviet Air Force)

RaVe_N
07-08-2007, 06:11 AM
Try here there are lots of links in the posts
http://8raven8.proboards44.com/index.cgi?board=wwi

Blutarski2004
07-08-2007, 07:29 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
Howdy all!

I'm doing a game about the old "canvas" days of dogfighting, and I was wondering if any have good book references on the performance of World War I recon and bomber aircraft? I'm looking for data beyond just ceiling and top speed... some more subjective data like manuverablility, roll rate, energy bleed, reliability and so forth. </div></BLOCKQUOTE>



..... Try these:

French Aircraft of WW1
Davilla & Soltan

British Aeroplanes 1914-1918
J M Bruce

German Aircraft of the First World War
Grey & Thetford

Go here - http://www.theaerodrome.com/forum/forum_index.php

and here - http://www.flightglobal.com/pdfarchive/index.html

sightreader
07-09-2007, 10:32 AM
Hey, thank you guys so much for the leads! I've been browsing them, and after some preliminary reading, I have a lot of questions about the British D.H. 4.

The top speed of this aircraft is listed as 143 mph (the Fokker DVII could only make 124 mph), and in addition some reports claim that it could manuver "as well as many fighters". The American Liberty variant has a listed speed of 123 mph... much more reasonable... but what of that 143 mph figure? In combination with its massive production numbers, such statistics should have been enough to offset its vulnerability - an exposed fuel tank sitting between the pilot and the observer - but despite this I don't hear about the war being much affected by them. Quite to the contrary, I hear of DH4s being mobbed by fighters and chopped down in droves, hardly what I would expect of an airplane that is supposed to be able to manuver with them - or at the very least be able to run away easily.

Can anyone shed light on this? Thanks!

sightreader
07-09-2007, 10:34 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Cajun76:
VVS Voenno-Vosdushniye Sili (Soviet Air Force) </div></BLOCKQUOTE>

That's a real mouthful... no WONDER I couldn't figure out what it stood for.

Blutarski2004
07-10-2007, 09:14 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
Hey, thank you guys so much for the leads! I've been browsing them, and after some preliminary reading, I have a lot of questions about the British D.H. 4.

The top speed of this aircraft is listed as 143 mph (the Fokker DVII could only make 124 mph), and in addition some reports claim that it could manuver "as well as many fighters". The American Liberty variant has a listed speed of 123 mph... much more reasonable... but what of that 143 mph figure? In combination with its massive production numbers, such statistics should have been enough to offset its vulnerability - an exposed fuel tank sitting between the pilot and the observer - but despite this I don't hear about the war being much affected by them. Quite to the contrary, I hear of DH4s being mobbed by fighters and chopped down in droves, hardly what I would expect of an airplane that is supposed to be able to manuver with them - or at the very least be able to run away easily.

Can anyone shed light on this? Thanks! </div></BLOCKQUOTE>


..... The de Havilland DH.4 was fitted with a wide array ofdifferent engine types during its production run - two variants of 230hp BHP, 230hp Siddely Puma, 250hp Rolls-Royce Eagle Mk III, 322-325hp Rolls-Royce Eagles Mk VI-VII, 375hp Rolls-Royce Mk VIII, 353hp Rolls-Royce "G" (Experimental), 200hp R.A.F. 3a, 260hp Fiat, 300hp Renault, and 400hp Liberty.

It was also experimentally tested with a 400hp Sunbeam Matabele and the Ricardo-Halford Inverted Supercharger Engine.

As of 31 October 1918, the RAF had 548 DH.4's on hand:

373 powered by various Mks of R/R engines.
72 powered by 200hp RAF 3a engines.
98 powered by various 230hp BHP engines.
5 powered by 260hp Fiat engines.

The DH.4, powered by the 375hp R/R Mk VIII was tested at 143 mph speed at SL and was the fastest DH.4 model. I do not have a full set of SL speeds for other engine outfits, but I can provide comparative speeds at 10,000 ft altitude. All speeds given were obtained without bomb-load aboard (which would otherwise subtract about 5 to 10 mph at any given altitude):

230hp BHP (various)_____110-114 mph
230hp Siddely Puma______104 mph
250hp R/R Mk III________113 mph
375hp R/R Mk VIII_______133.5 mph
353hp R/R "G"___________118 mph
200hp RAF 3a____________117.5 mph
400hp Sunbeam Matabele__122 mph
260hp Fiat______________111 mph
400hp Liberty___________117 mph

Don't be thrown by the apparent discrepancies between performance and horsepower. HP ratings of these engines were the normally theoretical output calculations using bore, stroke, and compression ratio; they did not take into account the relative efficiency of the engine design with respect to its induction, exhaust, or carburetion systems.

The above data are taken from "British Aeroplanes 1914-1918" by J M Bruce.

- - -

As regards the Fokker D.VII, the 124 mph speed which you mention is SL speed. However, the later models of the D.VII, fitted with the BMW IIIa and the Mercedes D.IIIauv high-altitude engines, had exceptional power output at height. The D.VIIF (BMW IIIa engine) could reach 16,400 ft (5,000 m) in 14 minutes. By comparison, the 375hp R/R Mk VIII powered DH.4 required 20 minutes to reach the same height.

Note: Later German fighter designs, for tactical reasons, emphasized climb rate over level speed.



This is atually my favorite military aviation period.

sightreader
07-10-2007, 03:00 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Blutarski2004:
Don't be thrown by the apparent discrepancies between performance and horsepower. HP ratings of these engines were the normally theoretical output calculations using bore, stroke, and compression ratio; they did not take into account the relative efficiency of the engine design with respect to its induction, exhaust, or carburetion systems.
</div></BLOCKQUOTE>

Wow! Thanks so much for so much research and information! Obviously, DH4 performance varied widely with different engines. I'm still trying to figure out how I can get a copy of the reference books you guys mentioned: our library doesn't carry stuff quite that esoteric.

Any idea of the DH4's performance as far as manuverability and roll rate would be? I imagine it would bleed a lot of energy on a turn, being a heavy two-seater...

Once again, I can't thank you enough for all the information!

Blutarski2004
07-10-2007, 06:46 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
Wow! Thanks so much for so much research and information! Obviously, DH4 performance varied widely with different engines. I'm still trying to figure out how I can get a copy of the reference books you guys mentioned: our library doesn't carry stuff quite that esoteric.

Any idea of the DH4's performance as far as manuverability and roll rate would be? I imagine it would bleed a lot of energy on a turn, being a heavy two-seater...

Once again, I can't thank you enough for all the information! </div></BLOCKQUOTE>



..... Sharing info like this is one of the best things about the web. I've gotten mountains of great data from other folks, so I figure I'm just paying my obligation forward.

J M Bruce describes the DH.4 as one of the great a/c designs of its day. He quotes from various handling tests and comments as follows -

"Stability - Lateral very good; longitudinal very good; directional very good. Control - Stick. Dual for elevator and rudder. Machine is exceptionally comfortable to fly and very easy to land. Exceptionally light on controls."

"...the version with the Eagle VIII engine &lt;snip&gt; tended to be tail-heavy at full speed and nose-heavy with engine off, but ... the maneuverability remained very good."

"In performance the DH.4 surpassed all contemporary aeroplanes in its class (day-bomber), and bettered most of the fighting scouts then in service. Its high ceiling perticularly commended it to the bomber pilots of its day, and this desirable combination of speed, climb, and tractability would at first glance seem to make the DH.4 well-nigh invincible. More than once its speed and ceiling enabled it to escape from enemy fighters, but if it were intercepted and forced to fight it sometimes proved to be a comparatively easy victim. This vulnerability was attributed to the considerable distance which separated the pilot and observer.

The cockpits were arranged to give the pilot a good forward and downward view for bombing, and the observer a good field of fire for his Lewis gun. Thus the pilot's cockpitwas situated immediately under the centre-section, and the observer was several feet further aft; the main fuel tanks occupied the intervening space. This arrangement succeeded in its original object, but the distance between the cockpits that close and immediate cooperation between pilot and observer which was so essential in combat. The speaking-tube which connected the cockpits was of little practical use, and the fighting efficiency of the aeroplane suffered considerably from the separation of its crew. The observer had full dual control, with duplicated altimeter and air-speed indicator; his control column was detachable."


S!

sightreader
07-11-2007, 10:40 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Blutarski2004:
J M Bruce describes the DH.4 as one of the great a/c designs of its day. He quotes from various handling tests and comments as follows -
S! </div></BLOCKQUOTE>

Wow, that is absolutely AWESOME! That is precisely the sort of information I need! Thanks so much... I can't tell you how much that helps. I think I'll see if there's a way I can secure a copy of that book through inter-library loan or something, but I'm not sure they'll let me do that as I'm not a student at the local college any more...

Once again, thanks a ton!

Blutarski2004
07-12-2007, 09:41 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Blutarski2004:
J M Bruce describes the DH.4 as one of the great a/c designs of its day. He quotes from various handling tests and comments as follows -
S! </div></BLOCKQUOTE>

Wow, that is absolutely AWESOME! That is precisely the sort of information I need! Thanks so much... I can't tell you how much that helps. I think I'll see if there's a way I can secure a copy of that book through inter-library loan or something, but I'm not sure they'll let me do that as I'm not a student at the local college any more...

Once again, thanks a ton! </div></BLOCKQUOTE>


..... My pleasure. BTW, are you doing a board game or a miniatures game?

sightreader
07-12-2007, 03:27 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Blutarski2004:
..... My pleasure. BTW, are you doing a board game or a miniatures game? </div></BLOCKQUOTE>

Howdy Howdy sir!

It was originally based on Wings of War, in which cards with the pictured aircraft are manuvered across the table using other move cards. Aside from that, though, this game bears little resemblance to the original, as it has been modified to be easier to learn, faster to play, and a lot more realistic (i.e. you can use air combat strategy in it).

Hey, by the way, your link to "theaerodrome" is a HUGE help! The guys there tell me that very few of the 375 hp engines used in DH4 flight tests actually made it to the front, as most were allocated to the RNAS. The vast majority of DH4s were apparently installed with 275 hp or weaker engines, with the most common being 230 hp, making them meat on the table for the Germans!

Blutarski2004
07-12-2007, 10:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Blutarski2004:
..... My pleasure. BTW, are you doing a board game or a miniatures game? </div></BLOCKQUOTE>

Howdy Howdy sir!

It was originally based on Wings of War, in which cards with the pictured aircraft are manuvered across the table using other move cards. Aside from that, though, this game bears little resemblance to the original, as it has been modified to be easier to learn, faster to play, and a lot more realistic (i.e. you can use air combat strategy in it).

Hey, by the way, your link to "theaerodrome" is a HUGE help! The guys there tell me that very few of the 375 hp engines used in DH4 flight tests actually made it to the front, as most were allocated to the RNAS. The vast majority of DH4s were apparently installed with 275 hp or weaker engines, with the most common being 230 hp, making them meat on the table for the Germans! </div></BLOCKQUOTE>


..... The guys at the Aerodrome Forum REALLY know their stuff. If you have the time, do a little prospecting in the Aerodrome Forum archives; I found a great deal of really good material on WW1 a/c performance in there.



BTW - You might be interested to check this site out as well -

http://flyhi.de/games/wingsoverfrance1.html#play

Cajun76
07-13-2007, 01:16 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by sightreader:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Cajun76:
VVS Voenno-Vosdushniye Sili (Soviet Air Force) </div></BLOCKQUOTE>

That's a real mouthful... no WONDER I couldn't figure out what it stood for. </div></BLOCKQUOTE>

I just knew it was for the Soviet Air Force, and <STRIKE>Cryptic</STRIKE> Cryllic being what it is, I Googled VVS. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif

sightreader
07-13-2007, 10:56 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Cajun76:
I just knew it was for the Soviet Air Force, and <STRIKE>Cryptic</STRIKE> Cryllic being what it is, I Googled VVS. http://forums.ubi.com/groupee_common/emoticons/icon_biggrin.gif </div></BLOCKQUOTE>

Oh great... now I feel stupid. Oh wait... I *am* stupid... no WONDER it feels that way...