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General Forums => Aircraft and Vehicles => Topic started by: AirFlyer on August 09, 2008, 02:33:47 AM

Title: A6M2 Performance.
Post by: AirFlyer on August 09, 2008, 02:33:47 AM

An article on the A6M2's performance, interesting to see that the A6M2's top speed might of actually been 345 M.P.H.

http://www.j-aircraft.com/research/rdunn/zeroperformance/zero_performance.htm

ZERO-SEN Model 21 Performance: Unraveling Conflicting Data

INTRODUCTION

The Mitsubishi Type Zero Carrier Fighter Model 21 was the fighter that opened the war in the Pacific over Hawaii and the Philippines . It was the primary fighter used by the Japanese navy from the beginning of the war until early 1943 and remained in front line service until well into 1944. As important as this fighter was in the Pacific air war there is little agreement in published sources about some aspects of its performance. In particular, the aircraft's maximum speed is given by different post-war publications in a range from 316 mph to 345 mph. This disparity of nearly 30 m.p.h. is sufficiently broad that at the lower end the aircraft might be deemed relatively slow by 1942 fighter standards and at the upper end it might be considered relatively fast and definitely competitive. This article attempts to unravel conflicting data and provide a likely, if not definitive, answer to the question of the Zero's maximum speed.

Title: Re: A6M2 Performance.
Post by: Delirium on August 09, 2008, 02:47:17 AM

I don't see any mention of the octane of fuel involved in the article.

That can make for a huge difference in overall top speed.

Title: Re: A6M2 Performance.
Post by: AirFlyer on August 09, 2008, 12:38:00 PM

Quote from: Delirium on August 09, 2008, 02:47:17 AM

I don't see any mention of the octane of fuel involved in the article.

That can make for a huge difference in overall top speed.

True but it doesn't really de-base the theory of it being able to do 345mph. Considering that the article compares a lot of data from A6M2's that the Japanese were using, which mean with whatever octane fuel they were using, it was capable of getting the A6M2 to 345mph.

Title: Re: A6M2 Performance.
Post by: Delirium on August 09, 2008, 05:18:25 PM

Quote from: AirFlyer on August 09, 2008, 12:38:00 PM

Considering that the article compares a lot of data from A6M2's that the Japanese were using, which mean with whatever octane fuel they were using, it was capable of getting the A6M2 to 345mph.

By that standard, alot of planes were rated lower in the field than they were while they were being tested. My P38 was one of those unfortunate aircraft...

Title: Re: A6M2 Performance.
Post by: Seagoon on August 09, 2008, 11:37:48 PM

True story.. Visited the Pacific Aviation Museum in Oahu last year where they have one of the few A6M2s still in existence. The info card in front of it listed the top speed as.... 390 MPH! I audibly said to my wife "390 Miles Per Hour? Well maybe if you removed the wings and dropped it from a Betty..." One of the museum guys walked over and sheepishly put his hand over the number and said "yeah, we need to change that."

Anyway it occurs to me that given how stiff the control surfaces on the Zero become once you are above 320, at 345 the plane would be an unbending beast. Not very useful to be able to fly that fast if you can't change your attitude once you get there. No?

- SEAGOON

Title: Re: A6M2 Performance.
Post by: AirFlyer on August 10, 2008, 12:05:04 AM

345 isn't that bad, you might have to cut throttle on a beginning merge but I don't think it's an excuse to keep our A6M2 slower then it should be.

Title: Re: A6M2 Performance.
Post by: Angus on August 10, 2008, 03:21:58 PM

No way it was that fast.
At best in a shallow dive.
VNE perhaps?

Title: Re: A6M2 Performance.
Post by: 2bighorn on August 11, 2008, 09:07:52 AM

Quote from: Delirium on August 09, 2008, 02:47:17 AM

I don't see any mention of the octane of fuel involved in the article.

Not relevant really. It is noted at what MAP settings they were tested.

Quote from: Delirium on August 09, 2008, 02:47:17 AM

That can make for a huge difference in overall top speed.

Japanese engines were designed to run on fuel they had (87-92 octane). If A6M could run at 250 mm HG on 87 octane and reach certain speed, then at the same MAP 150 avgas wouldn't change much.

Title: Re: A6M2 Performance.
Post by: Angus on August 12, 2008, 01:39:06 PM

AFAIK, the a6m would have wing problems at that speed (skin), so as a max in level flight, it would be rather odd.
What would the HP be anyway?

Title: Re: A6M2 Performance.
Post by: Bubbajj on August 12, 2008, 02:35:15 PM

zekefights end up at 150mph and slower anyways. The only advantage to a few more MPH is getting around the map a bit quicker.

Title: Re: A6M2 Performance.
Post by: 2bighorn on August 12, 2008, 03:06:08 PM

Quote from: Angus on August 12, 2008, 01:39:06 PM

AFAIK, the a6m would have wing problems at that speed (skin), so as a max in level flight, it would be rather odd.

Skin was good for 380+mph. Model 11 could reach over 330mph in level flight. Model 21 was further improved (streamlined, heavier wing though), so it's possible it reached similar speeds.

Quote from: Angus on August 12, 2008, 01:39:06 PM

What would the HP be anyway?

For?

Title: Re: A6M2 Performance.
Post by: AirFlyer on August 12, 2008, 03:43:50 PM

Besides, the 345mph is only reached in overboost(wep), so it's not like it would always be that fast.

Title: Re: A6M2 Performance.
Post by: busa on August 17, 2008, 07:14:13 AM

The maximum speed of A6M2b Zero Mk.1 Mod.2 (Mod.21) is 331mph.
The maximum speed of A6M2a Zero Mk.1 Mod.1 (Mod.11) is 316mph.

Two airplanes were the same air frames.
However, the thickness of outer skin was different.
The main wings of A6M2a were twisted and its drag was large.

The maximum speed of Zero Mk.2 series is 335-351mph.

They were measured in military power.

However, WEP was given to A6M5 series in October, 1945.
But the maximum speed is not indicated in the performance table.
If WEP is given to A6M5 in AH, I will calculate it for Pyro.

Thank you for reading my poor English.

Title: Re: A6M2 Performance.
Post by: Anaxogoras on August 17, 2008, 05:30:31 PM

Quote from: Seagoon on August 09, 2008, 11:37:48 PM

True story.. Visited the Pacific Aviation Museum in Oahu last year where they have one of the few A6M2s still in existence. The info card in front of it listed the top speed as.... 390 MPH! I audibly said to my wife "390 Miles Per Hour? Well maybe if you removed the wings and dropped it from a Betty..." One of the museum guys walked over and sheepishly put his hand over the number and said "yeah, we need to change that."

- SEAGOON

Having worked at a place comparable to a museum (big public aquarium), I promise you that the sign still says 390mph.  Exhibit signage tends to be run by committees that never accomplish anything except for making things worse.  For example, we had a sign that made an outright false claim about the leopard shark, and it took 6 months to have it changed after I pointed it out. :rolleyes: :mad:  They even had a model shark jaw with the teeth in backwards and wouldn't take my word for until they asked the guy with the phd, and all the while 9 year olds were asking "aren't those teeth backwards?". :rofl

Title: Re: A6M2 Performance.
Post by: Cajunn on August 22, 2008, 07:47:51 AM

I've always understood that the Zero and the F4F had the same top speed of 331 mph, don't remember where I seen or read that but I do remember it clearly because of them being the same.

Title: Re: A6M2 Performance.
Post by: CAP1 on August 22, 2008, 09:26:09 AM

Quote from: Cajunn on August 22, 2008, 07:47:51 AM

I've always understood that the Zero and the F4F had the same top speed of 331 mph, don't remember where I seen or read that but I do remember it clearly because of them being the same.

you guys are all talking top speed. but no one is defining top speed though?


top speed=VNE? or top speed= top cruise speed?

Title: Re: A6M2 Performance.
Post by: Cajunn on August 22, 2008, 10:47:11 AM

Quote from: CAP1 on August 22, 2008, 09:26:09 AM

you guys are all talking top speed. but no one is defining top speed though?


top speed=VNE? or top speed= top cruise speed?

I would guess that is why there are so many different numbers out there because it depends on so many different things (altitude, fuel load etc.)

Title: Re: A6M2 Performance.
Post by: Karnak on August 22, 2008, 11:16:56 AM

I've read many accounts of F4F pilots who explained some of thier tactics by saying that the Zero was faster than the F4F and they couldn't run.

Title: Re: A6M2 Performance.
Post by: CAP1 on August 22, 2008, 12:14:25 PM

Quote from: Cajunn on August 22, 2008, 10:47:11 AM

I would guess that is why there are so many different numbers out there because it depends on so many different things (altitude, fuel load etc.)

yes, alt., fuel load, weather conditions, etc.

everyone's making a big fuss about the fuel they had, but i think the japanese had taken that into account when they built their planes.


VNE that i had mentioned is the never exceed speed.
 that was why i had asked what definition of top speed we were using.  top cruise speed(maximum structural cruise), leaves you with more speed to call on, even if you do have to pitch nose low to get it.

 really though, i think the top speeds aren't as important as things like wing loading, turning ability, e-retention, etc.

these planes certianly don't turnfight at their top speeds.

even in the attempts to re-set the fight, i think acceleration is more important than top speed.

Title: Re: A6M2 Performance.
Post by: killrDan on August 26, 2008, 07:18:36 AM

thanks for the info busa  :aok
 i love reading about my favorite plane
                   ,grey

Title: Re: A6M2 Performance.
Post by: Angus on August 26, 2008, 10:40:02 AM

Top speed is usually defined being the highest TAS in level flight.
So, it varies with alt and load....

Title: Re: A6M2 Performance.
Post by: CAP1 on August 26, 2008, 10:50:30 AM

Quote from: Angus on August 26, 2008, 10:40:02 AM

Top speed is usually defined being the highest TAS in level flight.
So, it varies with alt and load....

SO WE'RE TALKING MAX. STRUCTURAL  cruise then, as opposed to never exceed.......

Title: Re: A6M2 Performance.
Post by: Golfer on August 26, 2008, 11:48:51 AM

No they're talking about the highest true airspeed that can be attained in cruise flight.

Throw enough fuel at the problem and you'll go plenty fast and max out in the mid to upper 20's in most airplanes capable of producing power at those altitudes.  The heavier you are at a given altitude the more fuel you'll burn at that speed.  As the temperature changes is where you'll see the more drastic changes in performance which don't have anything to do with the maximum structural cruise published on your 172.

Title: Re: A6M2 Performance.
Post by: Angus on August 26, 2008, 12:20:41 PM

That would be the upper end of the most economical cruise speed.
That one is frequently free of quotes in aviation publishing.

Title: Re: A6M2 Performance.
Post by: 321BAR on August 26, 2008, 06:07:10 PM

Quote from: Bubbajj on August 12, 2008, 02:35:15 PM

zekefights end up at 150mph and slower anyways. The only advantage to a few more MPH is getting around the map a bit quicker.

Not truly, i've been able to keep that 5B at a somewhat ok speed and still get a good fight in, just harder to do against the turnfighters, but a BnZer or a fat ftr (P47/P51) low alt, i can get on its six and kill it if i have a little alt (2k+3k) on it, and an angle. the nme is runnin straight and maybe just pulled out of a fight and was slow, but it still dies :aok, tried it in a A6M2 but i cant get the kill at all  :lol, just cant do it

Title: Re: A6M2 Performance.
Post by: RipChord929 on August 26, 2008, 06:13:39 PM

Quote from: Anaxogoras on August 17, 2008, 05:30:31 PM

Having worked at a place comparable to a museum (big public aquarium), I promise you that the sign still says 390mph.  Exhibit signage tends to be run by committees that never accomplish anything except for making things worse.  For example, we had a sign that made an outright false claim about the leopard shark, and it took 6 months to have it changed after I pointed it out. :rolleyes: :mad:  They even had a model shark jaw with the teeth in backwards and wouldn't take my word for until they asked the guy with the phd, and all the while 9 year olds were asking "aren't those teeth backwards?". :rofl

Well, the overpaid eggheads have to justify their existance somehow right???

Title: Re: A6M2 Performance.
Post by: 321BAR on August 26, 2008, 06:16:01 PM

Quote from: RipChord929 on August 26, 2008, 06:13:39 PM

Well, the overpaid eggheads have to justify their existance somehow right???

:lol :lol :lol

Title: Re: A6M2 Performance.
Post by: Angus on August 27, 2008, 11:02:32 AM

So, commitees=people who have the power politically.
So, they are the eggheads right?

Title: Re: A6M2 Performance.
Post by: Anaxogoras on August 29, 2008, 08:56:49 AM

Committee people are hardly the types I would call "eggheads," at least, that's not how that word is traditionally used.  And as Angus points out, committees are the locus of power in institutions that are run by the incompetent and therefore threatened by individual ability.

Title: Re: A6M2 Performance.
Post by: MiloMorai on August 29, 2008, 09:25:38 AM

Don't know the source but probably from American testing. Speed is Vm.

(http://img.villagephotos.com/p/2005-12/1114844/Zekedata2.jpg)