Author Topic: Brewster Buffalo dive speed and handling  (Read 17769 times)

Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #30 on: June 07, 2010, 05:15:50 AM »
I should conduct more tests but often in the MA it feels like brewsters dive a bit too well and hold their e much longer than

I would expect (compared to the I-16). Sadly all I have is anicdotal information, "pilot A says a f4f could out dive a brewster", etc..

main question...

Unlike the P51 or Me 109s or many of the more 'famous' planes of WW2, there doesn't appear to be much information on the filght characteristics of the finish version of the arplane. furthermore, there are almost no finish Buffalows in exsistance today. What sources have people found?


If you don't have any data, maybe you should have started by doing some testing. If you think Brewster dives too well or holds E too well, why don't you test it against that I-16 for example. Allthough I suggest testing against planes with western airscrews at first because just by looking at the primary source data on I-16, it's pretty clear that its prop efficiency must have been quite poor.

Obviously testing against hard data on the Brewster is a better way to go but you could have at least done the above before starting one of these threads again.


"It is a capital mistake to theorize before one has data.  Insensibly one begins to twist facts to suit the theories, instead of theories to suit facts." (Sherlock Holmes)


Thank you Tango! A voice of reason. :)

The problem just is that threads in this forum usually have such a poor signal to noise ratio that the voice of reason seems to get lost into the mindless blah blah blah. :( I wish most people would at least try to approach these topics with some sort of analytical thinking.

The most popular line of thought in here seems to go like this...

Witch? Wood? Wooden Witch! BUUUURRRN!


B-239s may have had one engine, but that engine wasn't necessarily what the Finns put into it. Remember they were scrambling for anything they could, similar to the AVG. I think they put the engines from a DC-3 in them, or some other transport?

Model 239 had 1000hp G5 Cyclones from beginning to the end if we don't count couple experiments with Soviet M-62/63 engines. F2A-1 had a 940hp -34 variant of the Cyclone. -34 was a military variant and therefore was under the export ban.


Saxman, the 339 was an export version of the F2A3.

Incorrect. B339 is "export version" of the F2A-2.


239s would have less horsepower and less efficient props than the F2A2s.

"less efficient prop"? The 239s prop had a smaller diameter but it doesn't make it any "less efficient" per se. 239s had to harness 200hp less power so I'm sure that the actual prop efficiency coefficients were very comparable.


Also, the Brewster was supposed to be somewhat unstable,

Hmm...everything I've read says exactly the opposite.

From British Report No.B.A.1689. (July, 1941), Handling tests on Buffalo (Brewster A.S.430):

"Banked turns with one control fixed: Excellent turns with very little sideslip can be done on ailerons alone. Sudden application of the ailerons increases the rate of entry and also the sideslip on going into a turn and during the recovery. More use of control is always needed to recover than enter."

Brewster was rather directionally unstable until Pyro fixed it in the latest version. It is very nice and stable gun platform now as it should be, apart from the slight tendency for the combat trim to trim it tail heavy. Therefore I toggle combat trim once to trim the plane and then dial in negative elevator trim manually.


Before being shipped to Finland, the pilot armor, the self-sealing fuel tanks, and the tail hook were removed. Note that the Finns themselves restored the pilot armor once they received them.

<sigh> The integral 80 gallon wing tanks were never protected, on any of the Brewster fighters. F2A-2 and F2A-3 had other protected tanks though. Krusty, these kind of facts simply aren't that hard to double check. If you are uncertain of something it's better left unposted. Makes for less noise and more signal.
« Last Edit: June 07, 2010, 06:41:30 AM by Wmaker »
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Offline Grendel

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Re: Brewster Buffalo dive speed and handling
« Reply #31 on: June 07, 2010, 06:32:46 AM »
Also, the Brewster was supposed to be somewhat unstable, and yet in-game is probably one of the better gun platforms. Before being shipped to Finland, the pilot armor, the self-sealing fuel tanks, and the tail hook were removed. Note that the Finns themselves restored the pilot armor once they received them.

And when they arrived in Finland, the Brewsters received pilot armor, self sealing fuel tanks, new gunsights, new radios and also had the armanent upgraded. The Brewster in Finnish service were not just lightened acrobatic planes but fully equipped combat aeroplanes.

I also dare to disagree about the unstable comment. All pilot reports tell how pleasant the Brewster was to fly, how good its dive characterics were, how well it handled and how it was excellent gunnery platform.

g
« Last Edit: June 07, 2010, 06:37:15 AM by Grendel »

Offline gyrene81

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Re: Brewster Buffalo dive speed and handling
« Reply #32 on: June 07, 2010, 08:47:09 AM »
Also, spewing the "weighted down by armor" line is false. We took the armor OUT, the Finns put it back IN. Net gain: zero.
Krusty, the Finns put a 50 pound steel plate behind the seat, that did not replace the U.S. Navy armor that was in it originally. And yes the DC-3 used one version of the R-1820 Cyclone engine as did the Douglas SBD.  


According to Janes Fighting Aircraft of WWII HP ratings at alt for R-1820 engines used in the Buffalo:
Quote
The R-1820-G5 model used by by the B-239(F2A-1) was rated at 1000 h.p. for take off, 850 h.p. at 6000 ft, and 750 h.p. at 15.200 ft. (2100 rpm).

The R-1820-G105A used by the B-339(F2A-2) export models was rated at 1100 for take-off, (2.350 r.p.m.) 900 at 6700 ft. (2300), and 800 h.p. at 2350 rpm at 17,200 ft.

The R-1820-G205 used by the B-439(F2A-3) was rated at 1200 h.p. at 2,500 rpm at take off, 1000 h.p. at 2300 rpm at 6700 ft.; and 1000 hp at 2500 rpm at 14,200 ft.
Are the variances in HP ratings at altitude modeled in AH for any aircraft?

I also found that the engines suffered from "oil starvation" and oil leaks during high-g combat. LOL, if only that could be modeled in AH with people yanking on the stick for prolonged periods.




So, in an early-war PTO setup, what's a better representation of the F2A-3, the B-239 or the F4F-4 with 4 X Mother Deuce?
Actually, yes it would be a better sub for the F2A-3 but that's just my take on it. The B-239 in AH is great in early war ETO setups since that was its historical AO.
The F2A-3 had 4 Browning M2 .50 cal machine guns and max speed of 320mph at 14,500ft. The F4F-4 had 4 or 6 Browning M2 .50 cal machine guns and a max speed of 320mph at 18,000(?)ft. The flight characteristics are closer to what is described for the F2A-3 as well.




Side note, do any of the Brewster skins have FAF Major Luukkanen's(sp?) victory markings on the tail? I understand he used labels of Karelia beer instead of paint. LOL
« Last Edit: June 07, 2010, 08:53:58 AM by gyrene81 »
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Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #33 on: June 07, 2010, 09:30:01 AM »
Are the variances in HP ratings at altitude modeled in AH for any aircraft?

Yes, off course they are, in all aircraft...allthough the hp isn't really used as normal power unit for the jets and the rocket ship. ;) But yes, change of power/thrust is modelled per altitude and/or speed.

Side note, do any of the Brewster skins have FAF Major Luukkanen's(sp?) victory markings on the tail? I understand he used labels of Karelia beer instead of paint. LOL

The beer was called Lahden Erikois Olut but yes, it is in game courtesy of Greebo. :) Check out the BW-393 in game, the most succesful fighter aircraft in the history of aviation in terms of kills scored.

More about Luukkanen's plane:
http://www.kolumbus.fi/kari.stenman/2004_theme_14.html





« Last Edit: June 07, 2010, 09:33:43 AM by Wmaker »
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Offline dtango

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Re: Brewster Buffalo dive speed and handling
« Reply #34 on: June 07, 2010, 09:35:33 AM »
Are the variances in HP ratings at altitude modeled in AH for any aircraft?

As wmaker says the answer is of course yes.  We wouldn't expect anything less from HTC :).  To prove it let just look at the level speed charts for the B239 and I-16 in AH.



Notice how the lines are raggedy and also slope off?  That's because of the engine HP variation as it changes with altitude.  

I also purposely used this picture to compare the B-239 and the I-16.  Why are the shape of the curves so similar?  The I-16 uses Russian M-63 engine which were license built Wright R-1820's.  According to Graham White because of the shortage of parts when it came time to replace the original R-1820's in the B-239's the Finns used captured Soviet M-63's as replacements.

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« Last Edit: June 07, 2010, 09:39:24 AM by dtango »
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Offline dtango

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Re: Brewster Buffalo dive speed and handling
« Reply #35 on: June 07, 2010, 09:50:22 AM »
Thank you Tango! A voice of reason. :)

The problem just is that threads in this forum usually have such a poor signal to noise ratio that the voice of reason seems to get lost into the mindless blah blah blah. :( I wish most people would at least try to approach these topics with some sort of analytical thinking.

The most popular line of thought in here seems to go like this...

Witch? Wood? Wooden Witch! BUUUURRRN!

You betcha.  You can't defy aerodynamics.  You'll lose every time trying. ;)

Tango
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Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #36 on: June 07, 2010, 10:12:21 AM »
You can't defy aerodynamics.  You'll lose every time trying. ;)

Yeh...

At times it seems like people think they can chuck bunch of anecdotes into some converter which comes up with the flight model.

And it obviously must be the wrong anecdotes in their mind that get chucked in. :lol
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Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #37 on: June 07, 2010, 12:50:03 PM »
Here's a subjective tidbit from Dean's AHT regarding diving the Brewster:

An old Navy pilot recalled with evident relish "We used to dive those things; the Brewster would pick speed in a hurry." Diving characteristics, particularly if the aircraft center of gravity was not too far aft, were considered good, though the Finns reported "Ailerons became a little twisted while diving."
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Offline gyrene81

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Re: Brewster Buffalo dive speed and handling
« Reply #38 on: June 07, 2010, 01:18:10 PM »
Here's a subjective tidbit from Dean's AHT regarding diving the Brewster:

An old Navy pilot recalled with evident relish "We used to dive those things; the Brewster would pick speed in a hurry." Diving characteristics, particularly if the aircraft center of gravity was not too far aft, were considered good, though the Finns reported "Ailerons became a little twisted while diving."
Difference in flight characteristics would be indicative of differences in models. That Navy pilot would have been talking about the F2A-2 or F2A-3. The B-239/F2A-1 had a shorter fuselage than the F2A-3/B-439 and didn't they change something on the wings between the F2A-1 and the F2A-2 due to some control quirk found in early dive tests? If so that would explain the Finns report.

Gets mind boggling trying to keep up with the differences between US Navy and export models.  :rolleyes:

If anyone wants a photocopied version of a Brit Brewster pilots manual, here you go:
Britsh Brewster Pilot Manual
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Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #39 on: June 07, 2010, 01:31:43 PM »
Difference in flight characteristics would be indicative of differences in models. That Navy pilot would have been talking about the F2A-2 or F2A-3. The B-239/F2A-1 had a shorter fuselage than the F2A-3/B-439 and didn't they change something on the wings between the F2A-1 and the F2A-2 due to some control quirk found in early dive tests? If so that would explain the Finns report.

The basic geometry and aerodynamics are very close between the models and the Navy did have F2A-1s aswell. What of course affects diving is the weight...or the lack of.

Not that it matters, but I haven't noticed anything special in the dive acceleration of the AH Brewster. As a matter of fact, my subjective feeling is that lack of weight is very much noticeable and that prolonged dives against most fighters is just a sure way to blow the little E/altitude that you have. Again, just my experience.

The point I'm trying to make is that those that think Brewster in AH "dives a bit too well" should do some testing and put this "issue" into some sort of perspective and context.
« Last Edit: June 07, 2010, 01:34:11 PM by Wmaker »
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Offline gyrene81

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Re: Brewster Buffalo dive speed and handling
« Reply #40 on: June 07, 2010, 01:48:20 PM »
Didn't the U.S. Navy only take somewhere around 10-15 F2A-1s before the F2A-2 went into production? The rest of the order that wasn't accepted were the ones that went to Finland. And I know the U.S. Navy converted most if not all of the F2A-1's they had into F2A-2s.


I think it dives better than the A6M2 and the I-16...but that's about it.
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Offline Wmaker

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Re: Brewster Buffalo dive speed and handling
« Reply #41 on: June 07, 2010, 01:55:45 PM »
Didn't the U.S. Navy only take somewhere around 10-15 F2A-1s before the F2A-2 went into production? The rest of the order that wasn't accepted were the ones that went to Finland. And I know the U.S. Navy converted most if not all of the F2A-1's they had into F2A-2s.

11 F2A-1 remained and yes, they were converted but they also saw service as F2A-1s. Doesn't change the fact that you can't totally rule out the possibility. Not that it makes any difference either way. Just thought that I'd post something relevant regarding the question in the original post.
« Last Edit: June 07, 2010, 01:59:01 PM by Wmaker »
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Offline Charge

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Re: Brewster Buffalo dive speed and handling
« Reply #42 on: June 08, 2010, 03:16:15 AM »
"The B-239/F2A-1 had a shorter fuselage than the F2A-3/B-439"

I think it's the other way around. The engine weighed more in later models so the nose was shortened to get CoG back in place so the B-239 was actually the longer one.

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Offline gyrene81

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Re: Brewster Buffalo dive speed and handling
« Reply #43 on: June 08, 2010, 10:01:04 AM »
Actually Charge, if you read what manufacturing changes took place between the F2A-2 and the F2A-3 from the Naval Historical Center website:

Quote
The Navy ordered a final 108 Brewster fighters in January 1941. These F2A-3s featured a longer fuselage, increased fuel and ammunition capacity, additional armor and considerably greater weight. Range was better, but speed, maneuverability, climb rate and service ceiling were substantially degraded. By the beginning of the Pacific War, the F2A, by then also known by the popular name "Buffalo", was passing out of carrier squadron service in favor of the F4F-3. The "Buffalos" were transferred to the Marines, who assigned them to units defending Pacific island bases.

According to Wiki there was a 4 inch difference in length and ~900 lbs difference in weight between the A-1 and the A-3.
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Offline Badboy

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Re: Brewster Buffalo dive speed and handling
« Reply #44 on: June 08, 2010, 10:54:10 AM »
At times it seems like people think they can chuck bunch of anecdotes into some converter which comes up with the flight model.
And it obviously must be the wrong anecdotes in their mind that get chucked in.

That got a good laugh, thanks!!

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