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View Full Version : About the La's, for consideration.



Hunde_3.JG51
04-09-2004, 10:16 PM
*Please don't turn this into the usual nationalistic flame-fest.*

Just something to consider about the La-7 from "La-5/7 Fighters in Action."

"At maximum power the cockpit temperature rose to 40 degrees Celsius (104 degrees F) even while operating in the bitter cold of the Russian winter. The temperature rise was caused by the elimination of the cockpit air-inlets and poor thermal insulation between the cockpit and the engine bay. The situation was worsened by the hot oil lines running between the oil coller and the engine and passing directly beneath the pilots feet. Additionally, poor internal sealing allowed exhaust gases to enter the cockpit and the pilots reported the odor of exhaust gases and burning rubber in the cockpit. The lack of proper ventilation also increased condensation in the cockpit. Pilots also complained about excessive rudder pedal forces and the absence of an emergency canopy release. These poor operating conditions, even in normal flight, could lead to greatly increased pilot fatigue and a higher accident and combat loss rate.
The list of complaints over the La-7 prototype was long. In addition to poor ventilation, excessive rudder forces, and the lack of an emergency canopy release, complaints were made about the lack of a single control to regulate engine speed and propeller pitch, an automatic supercharger switchover, and a new cowl flap control system. Such devices were already in use on Germany's FW-190 (in 1941) where a single lever controlled engine speed and propeller pitch (supercharger switchover, fuel mixture, boost pressure were also controlled automatically). In the La-7 the pilot had to make up to eight seperate movements to properly control engine speed, propeller pitch, and supercharger boost----actions often difficult to accomplish in comabt.
Regrettably, of the long list of complaints, only two were incorporated into the production La-7 (the automatic propeller pitch change mechanism and the jettisonable canopy)."

During prototype testing:

"A maximum speed of 680km/h at an altitude of 6,000m was recorded with the La-7 prototype......A maximum speed of 597km/h was recorded at sea-level."

These are very close to Oleg's numbers.

"The performance of production La-7's, however, suffered from their being quickly built on the fast-moving assembly line. Nevertheless, the production La-7's increased performance (over the La-5FN) was still impressive.
The standard production La-7 had a top speed of 592km/h at sea-level -- 46km/h more than the La-5FN. At 6,100m the La-7 had a top speed of 665km/h -- 35km/h more than the La-5FN."

The numbers given for the La-5 standard are significantly less than what is in FB. "The La-5 prototype's speed at sea level was greater by 8km/h (4.9mph) [when compared to Lagg-3]. Compared to the prototype, the production La-5 suffered a slight loss in speed at sea-level (down to 509km/h), and a loss of 20km/h in overall top speed."

"Down to 509km/h", the La-5 '42 is capable of 550+km/h in FB at sea-level.

These numbers for the La-5, La-5FN, and La-7 are less than what we have in FB. Are the numbers for these planes based on prototypes?

I'm not trying to start anything, just putting this up for consideration and wondering if the numbers we have in FB are based on prototypes rather than production models. All tests above were performed and reported by the Soviets themselves. Again, I'm not claiming these as law, but I wanted to put them up for consideration. I recommend everyone read this book, btw, it gives great information about the Lavochkins which is hard to find.

http://www.brooksart.com/Icewarriors.jpg

Formerly Kyrule2
http://www.jg51.com/

[This message was edited by Hunde_3.JG51 on Fri April 09 2004 at 09:26 PM.]

Hunde_3.JG51
04-09-2004, 10:16 PM
*Please don't turn this into the usual nationalistic flame-fest.*

Just something to consider about the La-7 from "La-5/7 Fighters in Action."

"At maximum power the cockpit temperature rose to 40 degrees Celsius (104 degrees F) even while operating in the bitter cold of the Russian winter. The temperature rise was caused by the elimination of the cockpit air-inlets and poor thermal insulation between the cockpit and the engine bay. The situation was worsened by the hot oil lines running between the oil coller and the engine and passing directly beneath the pilots feet. Additionally, poor internal sealing allowed exhaust gases to enter the cockpit and the pilots reported the odor of exhaust gases and burning rubber in the cockpit. The lack of proper ventilation also increased condensation in the cockpit. Pilots also complained about excessive rudder pedal forces and the absence of an emergency canopy release. These poor operating conditions, even in normal flight, could lead to greatly increased pilot fatigue and a higher accident and combat loss rate.
The list of complaints over the La-7 prototype was long. In addition to poor ventilation, excessive rudder forces, and the lack of an emergency canopy release, complaints were made about the lack of a single control to regulate engine speed and propeller pitch, an automatic supercharger switchover, and a new cowl flap control system. Such devices were already in use on Germany's FW-190 (in 1941) where a single lever controlled engine speed and propeller pitch (supercharger switchover, fuel mixture, boost pressure were also controlled automatically). In the La-7 the pilot had to make up to eight seperate movements to properly control engine speed, propeller pitch, and supercharger boost----actions often difficult to accomplish in comabt.
Regrettably, of the long list of complaints, only two were incorporated into the production La-7 (the automatic propeller pitch change mechanism and the jettisonable canopy)."

During prototype testing:

"A maximum speed of 680km/h at an altitude of 6,000m was recorded with the La-7 prototype......A maximum speed of 597km/h was recorded at sea-level."

These are very close to Oleg's numbers.

"The performance of production La-7's, however, suffered from their being quickly built on the fast-moving assembly line. Nevertheless, the production La-7's increased performance (over the La-5FN) was still impressive.
The standard production La-7 had a top speed of 592km/h at sea-level -- 46km/h more than the La-5FN. At 6,100m the La-7 had a top speed of 665km/h -- 35km/h more than the La-5FN."

The numbers given for the La-5 standard are significantly less than what is in FB. "The La-5 prototype's speed at sea level was greater by 8km/h (4.9mph) [when compared to Lagg-3]. Compared to the prototype, the production La-5 suffered a slight loss in speed at sea-level (down to 509km/h), and a loss of 20km/h in overall top speed."

"Down to 509km/h", the La-5 '42 is capable of 550+km/h in FB at sea-level.

These numbers for the La-5, La-5FN, and La-7 are less than what we have in FB. Are the numbers for these planes based on prototypes?

I'm not trying to start anything, just putting this up for consideration and wondering if the numbers we have in FB are based on prototypes rather than production models. All tests above were performed and reported by the Soviets themselves. Again, I'm not claiming these as law, but I wanted to put them up for consideration. I recommend everyone read this book, btw, it gives great information about the Lavochkins which is hard to find.

http://www.brooksart.com/Icewarriors.jpg

Formerly Kyrule2
http://www.jg51.com/

[This message was edited by Hunde_3.JG51 on Fri April 09 2004 at 09:26 PM.]

GK.
04-09-2004, 10:20 PM
should post this in orr, you have valid data backing your claims.

LEXX_Luthor
04-09-2004, 10:24 PM
He/she has no in-game flight test data or complete written testing procedure.

Most real life complaints about La~7 came from Luftwaffe pilots, one area where FB simulates history exactly. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

Hunde_3.JG51
04-09-2004, 10:29 PM
Thanks Lexx for ignoring the very first sentence of my post (which was put in asteriks) and for starting the mud-slinging early. Didn't take long did it? And I specifically said this was being put up for consideration, I'm not trying to change the game. And these are Soviet tests, I'm sure Oleg has seen them already and in greater detail.

http://www.brooksart.com/Icewarriors.jpg

Formerly Kyrule2
http://www.jg51.com/

LEXX_Luthor
04-09-2004, 10:39 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Didn't take long did it?<HR></BLOCKQUOTE>No, but you left it in our hands to "consider" http://ubbxforums.ubi.com/images/smiley/35.gif

p1ngu666
04-09-2004, 10:57 PM
they didnt use forzah or whatever in those tests according to oleg i think

http://www.pingu666.modded.me.uk/mysig3.jpg
&lt;123_GWood_JG123&gt; NO SPAM!

LEXX_Luthor
04-09-2004, 11:09 PM
Yes, the need to provide complete testing procedure. Only when robban75 did that did he convince me about the old La~7 climbrate.

Now, in my own pre~AEP tests, La~5 *never* overheated until I climbed to ~4km, then it would overheat. For real, I could never get the thing to overheat until I climbed up there. Did my mix right too (I think). Don't know if its still like that cos since before AEP I stopped flying with Overheat cos otherwise the cyclical radiator setting commands would not allow me to sim with that stupid hud text in my face, and getting rid of hud text is more realistic than simming Overheat.

Hunde_3.JG51
04-09-2004, 11:11 PM
But why would they do speed tests with without boost, what would be the point? Otherwise the engine performance would be the same between La-5 '42 and La-7. I don't think aerodynamic changes would result in 80+km/h speed increase at sea-level.

http://www.brooksart.com/Icewarriors.jpg

Formerly Kyrule2
http://www.jg51.com/

LEXX_Luthor
04-09-2004, 11:31 PM
Hunde:: <BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>But why would they do speed tests with without boost, what would be the point?<HR></BLOCKQUOTE>I dunno, my guess is that "boost" is only for a short while or not "normal" or something. Also I read some throttles had wires that pilot had to break before throttling up so mech could tell if engine was abused. Ask Chimp.

Chromatorg
04-10-2004, 12:07 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Hunde_3.JG51:
But why would they do speed tests with without boost, what would be the point? Otherwise the engine performance would be the same between La-5 '42 and La-7. I don't think aerodynamic changes would result in 80+km/h speed increase at sea-level.
<HR></BLOCKQUOTE>

How about Yak1? Yak1-1941 do about 450 kph, Yak1-1943 do about 540 kph with only 150hp more... There are a lot of documents, some of them even in internet, where you can read serial production Lagg/ La perfomance. The FB perfomance is about match good/average perfomance of these tests. There you can see what perfomace difference between best and worst examplar is quite big. I.e. La7 in the FB is not a La7 from Kozedub which could do 640kph at sea lvl, but its not a defect one with 570 kph either.
And well, 509 kph for LA5... can be only with bomb&Rockets.

AirBot
04-10-2004, 03:22 AM
I believe Oleg has stated that FMs in FB are based on the best available performance numbers, rather than the actual production performance.
In other words, bad production quality isn't modelled in FB.

WUAF_Badsight
04-10-2004, 03:51 AM
no

oleg has said that the Russian planes in FB & IL2 before that are moddeled on the carefully conducted fighter tests they had after the end of WW2

for the German planes the Factory data was the best he came across (so he typed at ORR) & that was used for them

i havent seen anywhere where he said what data was used for the british planes but he also used factory data for the American planes

hasnt said at all yet what data he used for the japanese planes

clint-ruin
04-10-2004, 04:32 AM
Early war production quality is not factored in for the VVS [ie Leningrad made pre-manufacturing base shift Lagg 3 '41s].

Late war production quality is not factored in for the LW [ie Hungarian (?) built Bf109K4s].

Been that way for an awfully long time.

As far as I can tell the criteria for data selection is:

Reliable source with documented methodology. No "good" "bad" "better" "worse" allowed, must be hard numbers with specific in-cockpit and atmospheric settings at each stage documented.

Real world, rather than calculated engineering figures.

Must be from a production line aircraft rather than prototype.

Some aircraft [Bf-109Z, Go-229, I-185, MiG-3U] don't lend themselves to this very well, obviously.

In the case of conflicting data, different sources may be used. Oleg has stated in the past that they use "best data" for Japanese, German, American, British and other nations aircraft [whether this means factory data or prototypes or golden samples from the lines depends on what the best data is], and that Soviet aircraft use an average of in-production aircraft figures.

Don't complain to me if you don't think the Spit or 51 goes fast enough, that's just what Oleg has said about it :&gt;

http://home.iprimus.com.au/djgwen/fb/leninkoba.jpg

GK.
04-10-2004, 03:44 PM
its all your fault clint

clint-ruin
04-10-2004, 04:43 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by GK.:
its all your fault clint<HR></BLOCKQUOTE>

Oh alright I admit it. It was me! Muhahaa..

Hmm.

Anyhow, what we find if we load the object viewer for FB is:

La5:
Top Speed Sea Level [10 min boost] 540-558
Typical Mfg Data: 558-560

La5F:
Top Speed Sea Level [10 min boost] 550-558
Typical Mfg Data: 558-560
At 6250: 598-605

While I wouldn't bet on any one number in the object viewer being accurate, it does seem to indicate that more than one factories data has been looked at and averaged. Don't forget that quality control often varied wildly from factory to factory and it was a steady process of refinement both of the aircraft and of the mass production process itself in most of them.

The reason "top speed" and "best climb" are sometimes given without WEP/Boost in these types of tests is because the interest is in "...at max continuous power" rather than "...if boost works properly and you don't mind replacing the engine". Some other western tests that have been posted [P-39, P-47, Spitfire Vb] have been the same way.

http://users.bigpond.net.au/gwen/fb/leninkoba.jpg