N1K2 Flight Tests (Speed & Climb), Comments Pyro?

[Vermillion]

Ok guys here is an example that I was thinking of the other day, about the differences in secondary "references".

Look in just about any book, and see what the top speed of the Ki-84 is, remembering it has the same engine as the N1K2.

Complete Book of Fighters, lists the Ki-84's top speed  at 388 mph, at 22,000 ft.

Janes Fighting Aircraft of WWII, lists it at 426 mph, at 23,000 ft.

Francillon's, Japanese Aircraft of WWII, in the technical section lists it as 392 mph at 20,000 ft.

And most of the others books we use as references lists the Ki-84 in that 380-390 range.  So most of us would discount the Jane's number and claim the 380-390 number as "correct".

But then if you read Francillons description section at the very end, he tells of how a captured Ki-84 was tested at the Middletown Air Depot, in Pennsylvania, in 1946.  In this test the Ki-84 reached a speed of 427 mph at 21,000 ft.

So which is right?

Even Francillon who's book is considered one of the definite desktop references on Japanese WWII aircraft, contradicts himself and ends up with a supporting number for each range of max speeds.

This is why I'm very leary of discounting the AW chart data, which supposedly comes from primary source data, for data we dig out of secondary source desktop reference books.  

Even the best of these types of books contradict themselves.

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires "

[wells]

Another option is to compare to an aircraft of similarity where more data is known. (ie  F4u, F6f)

The R-2800 puts out 1650 hp @ 21k and the Homare 1625 hp @ 20k (pretty darn close).

The F4u has substantially more wing area than the George (drag), and the George is at least as aerodynamic as an F4u.  There's nothing really obvious sticking out on the George that would slow it down significantly.  There's no reason it shouldn't be as fast as an F4u.  However, it does seem to have a much smaller diameter propeller than the F4u and that will reduce efficiency a bit.  I measure 3.3m for the George compared to 4.0m on the F4u.  

This reduced thrust efficiency is offset by having less wing area and there's no reason not to expect the George to hit 400mph.

[SnakeEyes]

Is it possible that the 380-390 rating is based upon the performance that the Japanese got out of it (keeping in mind their fuel and engine problems), and that the 420-ish rating is a result of what the Americans got out of it in post-war testing (using better fuel)?

And, if so, which one should be depicted?

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SnakeEyes
o-o-o-
=4th Fighter Group=

[Vermillion]

Exactly SnakeEyes

That very well could be the problem.

In these games in the past, every aircraft is modeled as in "perfect" condition, so in my opinon you would use the higher results.

Even the American aircraft are modeled off of perfect test aircraft, under perfect maintenance, with good gasoline.

The US planes in the field wouldn't perform up to that rating either, so Its my opinon that you would have to do the same for other nationalities.

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires "

[SnakeEyes]

Tis true... of course my argument would be that, if the enemy planes were that close to ours in terms of performance, we would have sped P-47N & Ms, P-51Hs, Tempests, and F8F-1s to the field much faster than we did.  Of course there's a very large contingent that refuses to accept these aircraft for various reasons.  

Shrug... I suppose it's just a huge pet peeve of mine.  My thought is that if you're going to model an aircraft that had substantial flaws in a manner that make that plane perform to its theoretical ideal, it only seems fitting to include the aircraft that would have theoretically been rushed to the front to counter such a threat.

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SnakeEyes
o-o-o-
=4th Fighter Group=

[Vermillion]

arrrgghhhh.... tho it pains me

<punt>

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires "

[Downtown]

Part of the reason the Super Hot allied aircraft weren't rushed to the front was....

Cause they weren't needed.

On The History Channel the other night they talked of the Allied numbers of better than 10 to 1 over the Luftwaffe.

I have heard, that in the Pacific there were like 60 to 1 odds, of course in range to strike Japan were closer to 3 to 1. (Theatre wise you include South East Asia, Australlia, Indochina, China, the Phillippines, the Marianas, Etc. there were a lot of planes in the Pacific, but they weren't all a direct threat to Japan.)

I guess the thing we need to know here is what Pyro and HT used for reference material.

My guess (Er, should I have said that?)

take all the numbers you can find, add them together, and then divide by the number of numbers you initially used.  That is how you get an average.

I certainly hope that he didn't use AW Charts, cause that would be plagurizing from another sim.

I have no data on the performance of Japanese Aircraft, wish I had a source and it was different from yours.

Personally I would go with the Janes Numbers.

So, er, um, Pyro, HT, What numbers did you use?

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"I could feel the 20MM Cannon impacting behind me so I made myself small behind the pilot armor" Charlie Bond AVG
lkbrown1@tir.com
 http://www.tir.com/~lkbrown1
Very Opinionated Person.

[Vermillion]

Well I know Pyro didn't use the AW Charts for two reasons.

One is that there isn't enough data there to make a FM without doing alot of guessing.

Two, is that the AW charts were made from data that is readily available in the US from FLight Tests of captured Georges. So he didn't need too.

The Airforce & the Navy both had a George they flight tested and they're currently in their respective musuems.  

So if you know which documents to request from them, you can get the info from the government thru Freedom of Information Act requests (FOIA). But the trick is knowing what the documents are. I would love to order copies of these original documents.

But I agree Downtown, I would just like a yes or no on the issue of, Is the chart data correct or is the FM correct ?

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires "

[Pyro]

Hey Verm,

I can't answer for how another game models their planes.  I have seen a TAIC report on the N1K1 that showed performance similar to what you cite, but it's just an intel report where they try to ascertain the enemy's capabilities.  In the particular report on the N1K1 that I read, they found a wrecked George in the Phillipines and examined it.  They then made some estimations about the planes speed, climb, ceiling, range, payload, etc.  It's not based on flight-tests or anything like that.  It's just first line intelligence and I imagine they erred on the high side to make sure they don't get a nasty surprise.  

   

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Doug "Pyro" Balmos
HiTech Creations

[Vermillion]

Thanks Pyro appreciate the information.

PS: Whats the TAIC acronym? Don't recognize that one.

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Vermillion
WB's: (verm--), **MOL**, Men of Leisure,
"Real men fly Radials, Nancy Boys fly Spitfires "

[Sundog]

FYI, there was a recent article in `Flight Journal' Magazine, written by a former Grumman Test Pilot. He reported on flying the Hellcat and the Corsair. I suggest anyone interested in comparing the two, read it (I believe it is available in back issues, and the article was within the last 4 or 5 issues. Just look for the one with the article about the Grumman testpilot.)
 http://www.flightjournal.com/

Navy Taste Test
Feature by Corky Meyer
December 1998, pg. 44
(Hellcat vs. Corsair)

Up is not Always Easy
Feature by Corky Meyer
April 1999, pg. 56
(When the noise stops and gravity takes over)

Hope that helps.

[Pyro]

TAIC = Tactical Air Intelligence forgot what the last word stands for.  They published a bunch of intel reports on estimated enemy plane capabilities.



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Doug "Pyro" Balmos
HiTech Creations