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XyZspineZyX
08-30-2003, 08:43 PM
Salute All

While I was happy to see the Brewster 239 improved over what it was in the original FORGOTTEN BATTLES, in version 1.1b it seems a little too uber, in particular its high altitude performance and zoom climb. Which doesn't seem to match up with the historical data.

As part of my testing of aircraft in FORGOTTEN BATTLES 1.1b, I checked the speed and climbrate of the Brewster. Speed seemed ok, but climb was not.

I used the Online map which has a section of Finland's coastline and some Soviet islands. The Brewster was loaded with 100% fuel. I did the test from sea level, following Ian Boys' guidelines of starting the climb at 300 kph right on the wavetops. I used a radiator position of 2. I probably could have gotten better climbrate with the radiator closed, since the engine showed no signs of overheating. I did a total of 5 tests.

According to original documents from the Brewster Corporation detailing the Model 239 Brewster, which are in the Finnish museum, the Brewster 239 had a climbrate of 2 minutes to 5,000 ft, (1524 meters) and 6 minutes to 15,000 ft. (4520 meters) That was with 3 .50 calibre Machinguns, and 1 .30 calibre MG. The model in FB has 4 .50's and therefore would be heavier.

According to Oleg's Object Viewer Aircraft files, the Brewster has a climbrate of 4:12 to 3,000 meters.


My tests showed the following averaged results:

Time to 5,000 ft: 1:19

Time to 3,000 meters: 2:59

Time to 15,000 ft: 4:33

That translates to a climbrate of 3750 ft/min at low alt, and an averaged climbrate of 3350 ft/min to 15,000 ft.

Actual plane had a rate of 2500 ft/min right up to 15,000 ft.

It is pretty clear that the Brewster is overmodelled in its climbrate, which is what is giving it the great zoom and overmodelled high alt performance we see in the game.

Anyone who is interested, send me a PM, and I will send them a copy of my record files.

I have already sent them to Ian Boys.


Cheers RAF74 Buzzsaw



Message Edited on 08/30/0307:46PM by RAF74BuzzsawXO

XyZspineZyX
08-30-2003, 08:43 PM
Salute All

While I was happy to see the Brewster 239 improved over what it was in the original FORGOTTEN BATTLES, in version 1.1b it seems a little too uber, in particular its high altitude performance and zoom climb. Which doesn't seem to match up with the historical data.

As part of my testing of aircraft in FORGOTTEN BATTLES 1.1b, I checked the speed and climbrate of the Brewster. Speed seemed ok, but climb was not.

I used the Online map which has a section of Finland's coastline and some Soviet islands. The Brewster was loaded with 100% fuel. I did the test from sea level, following Ian Boys' guidelines of starting the climb at 300 kph right on the wavetops. I used a radiator position of 2. I probably could have gotten better climbrate with the radiator closed, since the engine showed no signs of overheating. I did a total of 5 tests.

According to original documents from the Brewster Corporation detailing the Model 239 Brewster, which are in the Finnish museum, the Brewster 239 had a climbrate of 2 minutes to 5,000 ft, (1524 meters) and 6 minutes to 15,000 ft. (4520 meters) That was with 3 .50 calibre Machinguns, and 1 .30 calibre MG. The model in FB has 4 .50's and therefore would be heavier.

According to Oleg's Object Viewer Aircraft files, the Brewster has a climbrate of 4:12 to 3,000 meters.


My tests showed the following averaged results:

Time to 5,000 ft: 1:19

Time to 3,000 meters: 2:59

Time to 15,000 ft: 4:33

That translates to a climbrate of 3750 ft/min at low alt, and an averaged climbrate of 3350 ft/min to 15,000 ft.

Actual plane had a rate of 2500 ft/min right up to 15,000 ft.

It is pretty clear that the Brewster is overmodelled in its climbrate, which is what is giving it the great zoom and overmodelled high alt performance we see in the game.

Anyone who is interested, send me a PM, and I will send them a copy of my record files.

I have already sent them to Ian Boys.


Cheers RAF74 Buzzsaw



Message Edited on 08/30/0307:46PM by RAF74BuzzsawXO

XyZspineZyX
08-30-2003, 09:41 PM
I'm going to fly this bird, then!!!

<center>

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XyZspineZyX
08-30-2003, 10:10 PM
Yeah, be sure you checked your FB findings with the official numbers from the FINNISH version. They stripped the Brewster so, it was alot less heavy and so, performance was better.

1 Judge not, that ye be not judged.
2 For with what judgment ye judge, ye
shall be judged: and with what
measure ye mete, it shall be
measured to you again.

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XyZspineZyX
08-30-2003, 10:30 PM
your right. Brewster, laGG 66th series, P39Q and IL-2 all climb too good. In original FB 109 Emils and F4 did the same, but now seems they are quite real.



<center>http://www.kurita.sk/PRIVATE/pictures/sig_il2.jpg

XyZspineZyX
08-30-2003, 10:33 PM
yea finns stripped it ...it flys sweet compared to US version

http://mudmovers.com/Sims/IL2/images/wallpaper/me262sharkt.jpg
U.S. infantry 84-91

XyZspineZyX
08-30-2003, 10:49 PM
And you will need it to be, in the Empire of the Sun Multiplayer Online Coop No 1, which will be released on our down load page when the Japanese Zero is released in FB.

Because 6 brewsters wearing US Naval Skins will be defending Wake island ( Islands in the Gulf of Finland Map) from an incomming Japanese attacking force of 8 Betty Bombers, 4 Val Dive Bombers, and 6 Japanese Zeros flown by human Multiplay pilots, unless you are flying on your own off line using Multiplay.

http://www.geocities.com/blackwulf1_2000/kg55.html

S!

XyZspineZyX
08-30-2003, 11:23 PM
Yep, Finns modified the Brewster so it performs better than the original version used in the States and documented by the manufacturer. That is the reason it doesn't compare to the documents U have read.

XyZspineZyX
08-31-2003, 01:23 AM
Salute

I would disagree with the comments by those who say the Finns modified it enough to allow for this climbrate.

They initially asked for changes to the aircraft when they ordered it from the factory. Those were their modifications, and why their plane is called the Model 239, and differs from the standard Buffalo. Some of the changes included removal of the deck arrestor hook, catapult fittings, etc.

The performance figures for that modified 'Export' version are what I am quoting as the historical figures.

Subsequent to that, the Finns also modified it by adding an extra .50 calibre machine gun, which ADDED to the weight and would have REDUCED the performance.

Any other modifications I have not heard of.

In any case, the difference in climbrate is 150%, between the listed Model 239 figures, and what I get. I don't believe they removed enough equipement to allow for that degree of performance improvement.

If someone has actual documentation to prove current performance, please post it. Otherwise your suggestions that the Finns modified the plane is just speculation.


RAF74 Buzzsaw



Message Edited on 08/31/0312:26AM by RAF74BuzzsawXO

XyZspineZyX
08-31-2003, 03:58 AM
Did you do this at 110% power or 100% power. From my understanding, the climbrates in the object viewer are attained climbing at 100% power, not 110%.

When I tested the Brewster at 100% power, it climbed from sea level to 3000 meters in 3min 50sec. I started the climb at 340kph, slightly faster than the 300kph you correctly noted, so that may account for the slightly faster rate I achieved than what is documented in FB.

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
08-31-2003, 04:28 AM
Actually, the "name" B-239 is a company model number, not a special name for a Finn version. The "F" (ie F2A-1,2,3)designation for "Buffalo" fighters was given by the Navy, but Brewster gave all its fighters in this line a "B-#39" model number. Export aircraft simply maintained their company model number. The B-239 was Brewster's second model in this line, and thats what the Finns got. The US Navy got B-239s and called them F2A-1s.

The B-239s sent to Finland did differ in some ways from the B-239s(F2A-1) that went to the Navy. The Finn version had a civil Wright engine (with exactly the same power ratings as the US Navy military engine), had different fuel delivery system, different radio, different propeller, and had been denavalized (arrestor gear removed).

Gross weight of the Finn's B-239 was about 5,276 lbs.

==============

I'm surprised your documents show a climb rate of 2,500 fpm for the B-239. Is that on Normal power or Military power?

"America's Hundred Thousand" lists the F2A-3 as having a climb rate of 2,600 fpm on military power at sea level. This remains virtually constant up to about 10,000 feet.
Gross weight for this plane was 6,637 lbs. The F2A-3's R-1820-40 Wright engine had a military power rating of 1,200 hp.

The Finnish B-239 (4 gun fighter configuration just like in FB) had a gross weight of 5,276 lbs, about 1,400 lbs lighter. The B-239's civil Wright R-1820-G5 had a military power rating of 1,000 hp.

That's a lot of weight difference, and only 200 hp less for the B-239. And its possible the Finn extracted even more weight. I think the B-239 should climb signifcantly better than the F2A-3, and I don't think 3,000 fpm or a little more is out of the range of possibilities.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-31-2003, 07:16 AM
Is this where you got 2,500 fpm?

http://members.cox.net/rowlandparks/b239.jpg


This is a copy of an original Brewster manual.

The 5000 feet in 2 minutes (2,500 fpm av) is **calculated** for Normal Power or 850 hp. It goes on to say that Military Power, 1000 hp, will produce better performance.

Actual testing may have produced something entirely different, as it often does, than what is calculated here. Who knows that Oleg got from his Finnish fans.

Before Oleg goes and changes the climb rate, I'd like to know what he based it on. Because unlike the P-47 roll issue that was supported with real test data, all I've ever seen for the B-239 is estimated data.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-31-2003, 12:07 PM
the brewster even if overmodelled still accelerates like a fat toaster and takes damage like a fuel air bomb with wings. one hit and it blows like old faithful. no need for worries from this fat porcupine with wings

www.fighterjocks.net (http://www.fighterjocks.net) home of the 11 time Champions Team AFJ. 6 Years Flying http://www.world-data-systems.com/aerofiles/albums/userpics/p47-22.jpg 47|FC=

XyZspineZyX
08-31-2003, 02:06 PM
i flew it inverted with max speed and climbed, climbed, and climbed some more until i got bored. never quit. quite odd me thinks?

XyZspineZyX
08-31-2003, 02:34 PM
RedDeth wrote:
- the brewster even if overmodelled still accelerates
- like a fat toaster and takes damage like a fuel air
- bomb with wings. one hit and it blows like old
- faithful. no need for worries from this fat
- porcupine with wings

I've flown it online against contemporary VVS planes and it's not to be dismissed. Its acceleration is slow, but with altitude, you can do well turning inside Russian planes. Since many online VVS pilots use turning tactics to evade, the B-239 is perfect for pulling lead and getting good shots. Its forward view is very good and it makes a very small target on no icon servers.

"During its combat career, the Finnish B-239 is credited with 496 kills, against 19 losses, for a victory ratio of 26 to 1. Finnish air force records credit 41 kills to a single B-239 before it was shot down."



http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
08-31-2003, 08:07 PM
Salute SkyChimp

Thankyou for your comments and your correction of my error.

However, while you did bring my attention to the fact the aircraft was tested at 'Normal' power, you also encouraged me to have a closer look at the Brewster document.

(by the way, if you have the URL of the document, please post it. I have lost it, and cannot post my copy, as I do not have webpage space)

What comes to light on more careful reading of the document sheds even more doubt on the climbrate as modelled in FB.

If you take a quick look at the page you posted, you will see the aircraft is tested at a weight of 5014 lbs with 110 gallons of fuel.

That is the weight of the aircraft WITHOUT GUNS, AMMUNITION AND AT 68% FUEL.

If you go back to page 2 of the document you will see that 5014 lbs is the weight of the aircraft WITHOUT its .50 cal and .30 cal guns or ammunition and with only 110 gallons of fuel. 160 gallons is a full fuel load.

If we want an accurate figure on what the aircraft weighed with fuel and ammunition, we can get that information from page 2 of the document, and also pages 28 and 29 where the weight of the Guns and ammunition is listed.

In total, with 3 .50 calibre guns and one .30 calibre, plus full ammunition and fuel, the normally loaded Model 239 comes in at 5737 lbs. And of course, the FB Brewster would weigh more, since it had 4 .50's instead of the standard armament. The difference in weight between a .30 cal with ammo and a .50 cal with ammo is 60 lbs. (See also pages 28 and 29)

That would then bring the overall normal loaded weight up to 5797 lbs.

That is 783 lbs more than the tested weight, an amount which would have a considerable effect on the aircraft's climbrate.

I will be doing some more tests of the Brewster's climbrate, using 100% power, Empty selected for loadout, and both 50% and 75 % selected for fuel load. I should then be able to average the results and get an estimated result for 68% fuel.

Of course, there is no way to subtract the weight of the guns, which will be an extra weight carried in my tests and will mean the aircraft is carrying more than it was in the Brewster company document.


RAF74 Buzzsaw

XyZspineZyX
08-31-2003, 09:13 PM
Salute

So I re-did the tests, using the following criteria:

1) 75% fuel load

2) Weapon loadout: Empty

3) 100% throttle setting

4) Radiator closed

According the Brewster Corporation documents, the Brewster 239 had a climbrate of 2 minutes to 5,000 ft, (1524 meters) and 6 minutes to 15,000 ft. (4520 meters)

According to Oleg's Object Viewer Aircraft files, the Brewster has a climbrate of 4:12 to 3,000 meters.


My tests showed the following averaged results:

Time to 5,000 ft: 1:24

Time to 3,000 meters: 3:04

Time to 15,000 ft: 4:48

That translates to a climbrate of 3571 ft/min at low alt, and an averaged climbrate of 3125 ft/min to 15,000 ft.

Additionally, I believe I could have gotten better results if I increased the steepness of my angle of climb.

Actual plane with no guns or ammunition, and a 68% fuel load had a rate of climb at normal power of 2500 ft/min right up to 15,000 ft.

So I stand by my original proposition that the Brewster is clearly overmodelled in its climbrate.


RAF74 Buzzsaw




Message Edited on 08/31/0308:45PM by RAF74BuzzsawXO

XyZspineZyX
08-31-2003, 09:19 PM
brewster is a fun plane but it will only shoot down noob to medium level pilots. any normal pilot in his right mind flys at high speed making the brewster harmless. as for real life well....i wasnt there but i bet a million dollars those finns would rather have a P-51 or dora

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XyZspineZyX
08-31-2003, 09:45 PM
I don't have the URL, because I don't rememebr where I got it.

But you are correct, the weight (5,014 lbs) for the 2 minute climb to 5,000 is a fighter with just the cowl guns, not wing guns. 5,276 adds a .50 cal machine gun in each wing.

And no B-239 could climb at 3,500 fpm, I agree with that.

But I'd still ike to see what docs Oleg used to model the plane. Everything on the chart I posted is estimated.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-31-2003, 09:55 PM
Salute Chimp

Have a look at the documents again.

5014 lbs is the weight with NO weapons. Zero. Nada. Zilch. http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif

XyZspineZyX
08-31-2003, 10:04 PM
RAF74BuzzsawXO wrote:
- Salute Chimp
-
- Have a look at the documents again.
-
- 5014 lbs is the weight with NO weapons. Zero.
- Nada. Zilch. http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif
-
-

No it's not. 5014 lb includes a .50 and a .30 in the cowl. 5276 add a .50 in each wing.

You can't add 3 fifities and a thirty for just a little over 200 lbs.

http://members.cox.net/rowlandparks/b239_weights.jpg


Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
08-31-2003, 10:24 PM
RedDeth wrote:
- brewster is a fun plane but it will only shoot down
- noob to medium level pilots. any normal pilot in his
- right mind flys at high speed making the brewster
- harmless. as for real life well....i wasnt there but
- i bet a million dollars those finns would rather
- have a P-51 or dora
-

I didn't realize those planes were available in 1941 when Finland entered the war against Russia. And if we're not comparing apples to apples, why stop at the P-51?...why not the P-80 or an F-16...

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
08-31-2003, 10:29 PM
Salute

My mistake again. Thought it said one .30 and one .50.

(Eyesight must be going... /i/smilies/16x16_smiley-wink.gif )

211 lbs by the way does not include ammo. That is extra and brings the total to 262 lbs more, which is why you get 5276 when you add the twin .50's in the wings to the 5014 basic. And of course, you also need to add the extra 50 gallons of gasoline to fill the tanks to maximum, which brings the weight up to 5476 lbs, plus you need to add the weight of a .50 calibre subbed for a .30, (you can find that difference on page 28-29) which is 60 lbs including ammo, for a net grand total, fully fueled with ammo of 5536 lbs. Which is 522 lbs more than the tested plane.

In any case, the exact weight doesn't affect the results of my test. Which is still a clear indication that the plane climbs too well.


Cheers RAF74 Buzzsaw



Message Edited on 08/31/0309:38PM by RAF74BuzzsawXO

XyZspineZyX
08-31-2003, 10:32 PM
I agree it climbs too well.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
09-01-2003, 12:43 AM
At the bottom of the first page you posted SkyChimp, it says that the above calculations (the one showing an estimated climbrate) were made with all external armaments in place. If the plane is bare, then what is the document referring to?

Also, I would like to see what information Oleg is using. Test result from the FAF would be interesting reading to see how actual performance differed from the calculated performance.

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
09-01-2003, 12:57 AM
Here is some useful links to Finnish version of Buffalo (aka B-239):
http://www.xs4all.nl/~fbonne/warbirds/ww2htmls/brewf2a.html
http://koti.mbnet.fi/~jjuvonen/planes/brewster.html
http://www.fiddlersgreen.net/aircraft/WWII/buffalo/buff_info/buff_info.htm


Especially these guys should have answer to your questions: http://www.virtualpilots.fi/en/

About guns used in B-239s: http://www.danford.net/gun.htm
(Those planes were sold without armaments originally and Finns used their own versions of .50cal guns. I don´t know were those guns lighter than American original guns.)
Here is guns technical data from link mentioned above:

Finnish BMG LKk/42 CAL .50 BMG:
Weight of basic weapon: 24,25 kg
One barreled version with magazines: 56 kg
100 round belt weight: 13,2 kg
Firing speed: 1000-1100 rounds/minute
Bullet velocity: 700-835 m/s
Lenght of the rifling: 810 mm

----------------------------------------
"Only Finland - superb, nay, sublime - in the jaws of peril -
Finland shows what free men can do."
Winston Churchill 1940
<center>http://koti.mbnet.fi/~aval2/F19_Kunkkula.jpg </center>

Message Edited on 09/01/03 01:59AM by Kunkkula

Message Edited on 09/01/0302:05AM by Kunkkula

XyZspineZyX
09-01-2003, 02:11 AM
Salute Kunkula

Thankyou for your post. However, the links you have are all secondary sources and thus of no real use.

We already have copies of the original Brewster Company documents which were shipped in the crates with the Brewster Model 239 which the Finns received.

We can only rely on that data, unless someone has original Finnish test documents on the Brewsters performance.

If someone has those, please post them.


Thankyou RAF74 Buzzsaw

XyZspineZyX
09-01-2003, 02:43 AM
Buzzsaw, I asked SkyChimp to clarify the document but he's yet to respond. When you say that 5014 is the weight of the Brewster bare, it goes against my understanding of such documents. When a plane is manufactured, it has a weight which refers to what I believe you are calling the "bare" weight known as the empty weight. Gross weight, which the document refers to, is the maximum load the manufacturer recommneds that the plane should not exceed. The difference between the two, "empty" and "gross", is what is referred to as "useful loads". The document outlines different types.

The gross weight of 5014lbs, therefore, would be the empty weight plus useful load for a fighter configured with 110 gallons of fuel, one 30 cal. and three 50 cal guns.

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
09-01-2003, 02:59 AM
Chadburn wrote:
- At the bottom of the first page you posted SkyChimp,
- it says that the above calculations (the one showing
- an estimated climbrate) were made with all external
- armaments in place. If the plane is bare, then what
- is the document referring to?


Sorry, I didn't see your post.

The plane wasn't bare.

The document I posted listed the Buffalo in several different configurations. They were:

1) Fighter, with 2 cowl guns, and 110 gallons of fuel
2) Bomber, with 2 cowl guns, 2x 116 lb bombs, and 110 gallons of fuel
3) Fighter, with 2 cowl guns, and 160 gallons of fuel
4) Fighter, with 2 cowl guns, 2 wing guns, and 110 gallons of fuel

The weights listed on the page I posted listed weight for the Buffalo in the fighter configuration (#1) and bomber configuration (#2). In other words, the weight listed were for those planes, ready to fly and fight in those configurations.

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
09-01-2003, 03:02 AM
Remember guys here that U R only relying on a single document from the original manufacturer. U R not even sure about what alternations Finns did to the Brewsters. Thus U have no clear documentation of the overmodeling of Brewster.

U should rather look at some FINNISH documentation. That documentation exist, that is 100% sure. Unfortunately those documents are in Finland and absolutely not in any web-page. Like already mentioned e.g. Virtualpilots must have some documents. I know that they cooperate with Oleg, and that is where Oleg must have gotten his documentaion. Also Finnish war museum has documentation and it is available there and only there. Those documents can't be ordered if I am not wrong.

So again, post on the Virtualpilots email-list. Those guys know the business and they will be happy to enlighten U.

XyZspineZyX
09-01-2003, 03:09 AM
Chadburn wrote:

- The gross weight of 5014lbs, therefore, would be the
- empty weight plus useful load for a fighter
- configured with 110 gallons of fuel, one 30 cal. and
- three 50 cal guns.


Not "Empty Weight." Rather "Basic Weight." "Empty Weight" is the plane, empty of all fluids, guns, etc..

"Basic Weight" is the "Empty Weight" plus "Fixed Useful Load" (ie: trapped fluids, crew, guns, provisions for bombs, communication equipment, navigation equipment, pyrotechnics, misc. equipment).

The "Gross Weight" is the "Basic Weight" plus "Disposable Load" (ie: useable oil, ammo, internal fuel, bombs).

"Useful Load" is the combined weight of the "Fixed Useful Load" and the "Disposable Load."

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg

XyZspineZyX
09-01-2003, 03:11 AM
Thanks. I was looking only at the first sheet but on the second I now see the gross weight of 5276 for the four gun configuration you describe.

Thanks

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
09-01-2003, 03:27 AM
Porta_ wrote:
- Remember guys here that U R only relying on a single
- document from the original manufacturer. U R not
- even sure about what alternations Finns did to the
- Brewsters. Thus U have no clear documentation of the
- overmodeling of Brewster.
-
- U should rather look at some FINNISH documentation.
- That documentation exist, that is 100% sure.
- Unfortunately those documents are in Finland and
- absolutely not in any web-page. Like already
- mentioned e.g. Virtualpilots must have some
- documents. I know that they cooperate with Oleg, and
- that is where Oleg must have gotten his
- documentaion. Also Finnish war museum has
- documentation and it is available there and only
- there. Those documents can't be ordered if I am not
- wrong.
-
- So again, post on the Virtualpilots email-list.
- Those guys know the business and they will be happy
- to enlighten U.
-
-

Actually, I'm not concerned that we are looking at wrong documentation for a Finnish plane.

The US Navy obtained 11 Brewster B-239s. They became F2A-1s in the Navy.

The Finns acquired 44 B-239s.

Even though both countries got B-239s, there were differences between the US Navy plane and the Finnish export plane. But the Finns did not perform the alterations, the changes were performed at the Brewster factory before they were shipped.

Essentially, Brewster changed the B-239 in the following manner before shipping them to the Finns:

1) Changed the engine from a military Wright Cyclone R-1820-34 to a civil Wright R-1820-G5. There were slight differences, but both engines developed identical power. Neither was superior to the other, really.

2) De-navalized it. IE, the removed the arresting gear.

3) Gave it a different radio.

4) Installed .50 cal machine guns in the wings.


There wasn't a lot the Finns could do to it once they got it. B-239s had no armor at all; no pilot armor or self-sealing tanks. So they couldn't strip that to make it lighter.

The Finns did generally remove the US Navy tubular gun site and replaced it with a reflector site.

But otherwise, I don't know of anything further the Finns did to their planes. The differnces in the US planes and the Finnish planes were done by Brewster, not the Finns, except in the case of the gunsite.



Additionally, the documents I posted comes from a Brewster manual for the B-239s that were shipped to the Finns. In fact, I got the B-239 manual from a Finnish site. So the pages I posted are specifically for the Finnish version of the B-239. See below:

http://members.cox.net/rowlandparks/finnmanual.jpg


Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg


Message Edited on 09/01/0306:33AM by SkyChimp

XyZspineZyX
09-01-2003, 03:40 AM
Skykchimp, I believe that the 239s that were sent to Finland arrived without guns or instruments.

At least that is the legend...

<center><FONT color="red">[b]BlitzPig_EL</FONT>[B]<CENTER> http://old.jccc.net/~droberts/p40/images/p40home.gif
</img>.
"All men dream, but not equally. Those who dream by night in the dusty recesses of their minds, wake in the day that it was vanity:
but the dreamers of the day are dangerous men, for they may act on their dreams with open eyes, to make them possible. "
--T.E. Lawrence

XyZspineZyX
09-01-2003, 03:48 AM
It would appear that the information in FB comes from a three volume collection by Jukka Raunio called Lent¤j¤n n¤k¶kulma (The Pilot's Point of View). Probably volume II which deals with FAF fighters and was published in 1993.

The reason I say this is because a secondary source gives credit to Raunio as the source for their information on the FAF B-239. What's interesting is that the empty and take off weights of this source match FB's object viewer of 2020kg and 2415kg respectively. As you can see, these are much lighter than the weights in the documents that accompanied the B-239's. I'm wondering what Raunio is basing this on? If someone had access to this volume and checked it could be helpful.



http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
09-01-2003, 03:59 AM
The object viewer listed the take-off weight as 5,324 lbs. That's a few pounds heavier than Brewster's listed weight of 5,276 lbs.

(The document I have lists the "Bomber" version as weighing 5,267lbs, and the 4 gun "Fighter" version weighing 5,276lbs.)

Regards,

SkyChimp

http://members.cox.net/rowlandparks/corsairs.jpg


Message Edited on 09/01/0307:24AM by SkyChimp

XyZspineZyX
09-01-2003, 04:16 AM
Sorry, what I meant was the difference in the empty and takeoff weights was less than what the accompanying documents state. In FB the weight difference is only 395kg or 869lbs, whereas the useful load in the document you posted showed 1585lbs or 720kg.

Perhaps in FB empty means simply without ammo and no fuel but with full armament.

http://home.cogeco.ca/~jkinley/rcafpost.jpg

XyZspineZyX
09-01-2003, 05:17 AM
i apologize chadburn. i was stating that the brewster even if a little overmodelled wasnt much of a threat. now i realize this little plane must terrorize you onlinehttp://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif were talking ww2 and you go out on a goosechase for f16s . you were the one posting real life stats about the plane chadburn as if to say it should shoot down some serious stuff. i was just replying in essance. this is a game and the real life kills dont matter much for gaming purposes. the mechanical aspects are cool for reference but just because its succesful for the finns doesnt mean its a menace in the air. remember those russkies flew low ....in fb the aces fly high and fast. again i apologize for your circular logic. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif buh bye !

www.fighterjocks.net (http://www.fighterjocks.net) home of the 11 time Champions Team AFJ. 6 Years Flying http://www.world-data-systems.com/aerofiles/albums/userpics/p47-22.jpg 47|FC=

XyZspineZyX
09-01-2003, 06:15 AM
This is the second time you've missed my point. I said against contemporary planes(as in planes of the same era) it could do okay. I even suggested a tactic I've used with some success in a '41-42 server.

Of course the P-51 and Dora are superior planes, so I'll give you credit for a firm grasp of the obvious. But they weren't available in 42 anymore than a P-80 or an F-16. That's my point.

Oh, and thanks for the apology.

http://home.cogeco.ca/~jkinley/rcafpost.jpg

Message Edited on 09/01/0302:04AM by Chadburn

XyZspineZyX
09-01-2003, 01:45 PM
Here's some test figures taken from "Finnish fighter aces" an Osprey publishing.

Brewster B-239
Test aircraft: BW-366
date: 20 may 1940
armament: 3 x 12.7mm, 1 x 7.7mm

Test was made fully fueled and fully armed. No external loads.


climbrate:
1000m 1min 25sec
2000m 2min 30sec
3000m 4min 10sec
4000m 5min 35sec
5000m 7min 10sec
6000m 9min 15sec

1000m ~= 3300 feet

Not sure are these figures from a "ramp start" or a "flying start" http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

XyZspineZyX
09-01-2003, 01:55 PM
Few precisions:
- USA sold those planes without armaments, so that is not just legend. USA was officially neutral with Finno-Russian war. Therefore planes were sold without armament.
- Brewsters were assembled in Sweden, not USA. Norwegian mechanics did assembling job in Swedish factory near Trollhattan. Finnish and American pilots together with few foreign volunteers did then fly those planes to Finland. Only half dozen of planes were fly to Finland before Winter War ended 13th March 1940. Rest planes were fly from Sweden during following months.
- Finns made several changes to assembled planes during the truce (spring 1940 - summer 1941), including the installation of an armored headrest and seat back, plus a reflector gunsight in place of the original bead and ring.
- While coming to the middle of Continuation war (1941-1944) lack of spare parts was serious. In an attempt to overcome these problems, at least six B-239s were fitted with captured Russian M-63 radials (these were license-built versions of the Wright Cyclone).

Story of planes way to Finland in internet:
http://www.sci.fi/~fta/BWtoFAF1.htm



----------------------------------------
"Only Finland - superb, nay, sublime - in the jaws of peril -
Finland shows what free men can do."
Winston Churchill 1940
<center>http://koti.mbnet.fi/~aval2/F19_Kunkkula.jpg </center>

Message Edited on 09/01/0303:02PM by Kunkkula

XyZspineZyX
09-01-2003, 02:15 PM
That plane is for sure overmodel if you compare it with the russian planes in the years 1941-42. I can' t belive that plane can turn and fight at low altitude better then I-16, i can belive had more climb rate but not the same agility.

Best regards

Albe

XyZspineZyX
09-01-2003, 09:36 PM
Salute

Here is the link to the copies of the original Brewster Manufacturing document which we have been referring to:

http://www.hut.fi/~ssipila/brewster/brewster-350.pdf


RAF74 Buzzsaw

XyZspineZyX
09-01-2003, 09:37 PM
Salute

Additionally, here is the pilot's manual:

http://www.hut.fi/~ssipila/brewster/brewster-353.pdf


RAF74 Buzzsaw

XyZspineZyX
09-01-2003, 10:18 PM
Salute

Here is an original Finnish document which shows climbrate for Brewster, kindly posted by Jippo:

http://www.kolumbus.fi/jan.niukkanen/BW.jpg


Document shows climbrate of approx. 12.8 meters per second, which translates to 2519 ft per minute, very similar to what Brewster company document says.

So it is clear that Finnish documents do not show the climbrate which the FORGOTTEN BATTLES 1.1b Brewster achieves.

It is overmodelled and should be reduced.


RAF74 Buzzsaw

XyZspineZyX
09-02-2003, 10:45 AM
RAF74BuzzsawXO wrote:
- Salute
-
- Additionally, here is the pilot's manual:
-

And here's a link for the RAF pilot's manual for the Buffalo:
http://www.danford.net/buffpilotmanual.pdf

-----
In memory of 'The Few'
<img src=http://www.lima1.co.uk/Sharkey/spitfire.jpg>
The Tangmere Pilots - http://www.tangmerepilots-raf.co.uk/
Know your enemy and know yourself; in a hundred battles, you will never be defeated.

XyZspineZyX
09-02-2003, 11:39 AM
Just this Albe, if you enter to Turn fight with brewster with 1941-42 VVS planes you will loose. It was also so in reality.


SA5_Albe wrote:
- That plane is for sure overmodel if you compare it
- with the russian planes in the years 1941-42. I can'
- t belive that plane can turn and fight at low
- altitude better then I-16, i can belive had more
- climb rate but not the same agility.
-
- Best regards
-
- Albe
-
-

XyZspineZyX
09-02-2003, 12:13 PM
S! All!

I am glad you guys are debating this. I for one don't give a rip what the climb rate of the Brewster Buffallo is. The only thing I know is that the Japanease liked flying against it...

But it says something that this level of research can be done on the planes in the game and that for the most part the flight model in the game passes the test. That really says something about the quality of the game, and about the quality of the flight simulator community in general.

While I don't care about the climb rate of the Buffallo, I do care about having a reasonably accurate flight model. I SALUTE you gentlemen for taking to time to help improve upon in!

RAF74_Wall-dog

<a href="http://www.doghousecomputing.com/scorchedearth">http://www.doghousecomputing.com/scorchedearth/images/parsersmall.jpg

XyZspineZyX
09-02-2003, 01:21 PM
Yeah and it's nice that it's so polite for a change /i/smilies/16x16_smiley-happy.gif

I want more threads like this one

No1RAAF_Pourshot


http://members.optusnet.com.au/~andycarroll68/CAC-15.jpg

CAC CA-15 Kangaroo