Author Topic: ki84 speed????  (Read 16016 times)

Offline Karnak

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ki84 speed????
« Reply #30 on: November 01, 2004, 11:41:25 AM »
Quote
Originally posted by Wurger
So HTC should just model a plane's performance on what you think it should be so that you'll keep your account?    See ya...

Bazi

No.  HTC should model it how they think it should be modeled.  That my account is dependant on its modeling is not their responsibility and is solely up to me.
« Last Edit: November 01, 2004, 11:43:35 AM by Karnak »
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Offline Wurger

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ki84 speed????
« Reply #31 on: November 01, 2004, 11:50:23 AM »
Quote
Originally posted by Karnak
That my account is dependant on its modeling is not their responsibility and is solely up to me.


Exactly my point, so why mention it...

Bazi
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Offline Pongo

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ki84 speed????
« Reply #32 on: November 01, 2004, 11:50:55 AM »
Karnak. that is the begining of the fun not the end of it.

Offline Pyro

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ki84 speed????
« Reply #33 on: November 01, 2004, 11:54:40 AM »
Top speed is 388, except for the fact that it's not making full power right now.  

The WEP issue is a confusing one.  Busa has been doing a lot of research for me over in Japan on the N1K and also the Ki-84.  It's not very clear-cut as the engine had various restrictions placed upon it at various times and the IJA and IJN did not treat the engines the same.  His research leaned toward the Ki-84 not making use of WEP while the N1K did, but again, it is not a clear-cut situation and is the source of much debate.

Offline Charon

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ki84 speed????
« Reply #34 on: November 01, 2004, 11:56:10 AM »
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So HTC should just model a plane's performance on what you think it should be so that you'll keep your account? See ya...


With the Ki-84 there are several choices they could make, since the data is generally lacking. They  have picked the worst data set (or one of them) to use for the model.

Again, for all of its differences to oeprational standards, the Wright Field testing was detailed and generated some hard numbers with a production aircraft. It should be excessive compared to the war time average performance, but if you can't logically account for the HUGE 40 mph difference then this choice is questionable.

The same goes for the427 mph at 20,000 feet. (at a weight of 7490 pounds). It sounds like another 40+mph difference. If the weight variables or octane variable can't reasonably account for that, then the data set needs to be reconsidered.

It's not like we were expecting it to out turn a zero and out run a la-7. It would be nice to hear from Pyro why this was selected.

[edit: see Pyro replied while I was typing. Why 388, how can you account for the dramatic difference compared to WF? even with higher octane fuel?]

Charon
« Last Edit: November 01, 2004, 12:03:40 PM by Charon »

Offline Karnak

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ki84 speed????
« Reply #35 on: November 01, 2004, 11:57:06 AM »
Quote
Originally posted by Charon
The captured Wright Field example did 363 mph at sea level. Now it used higher octane fuel, but...

Would that generate a full 40 mph difference? It seems as if the worst data set was chosen here, and one that is hard to extrapolate with the Wright Field tests even if it was the best made, most polished Ki-84 of the war.

No, that would not have made it 40mph faster.  Maybe 20mph faster, at the outside.

Keep in mind that the reason it was being tested with 100 octane was to try to simulate the MW50 injection that they didn't have, but that the Japanese used operationally.  That is how I understand it anyways.
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Offline humble

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ki84 speed????
« Reply #36 on: November 01, 2004, 11:58:10 AM »
I'm a bit curious about the Ki-84 and whats realistic. A brief search on the web brought up a bunch of "performance" blurbs and I copied 1 that seemed middle of the road....

I]No Japanese fighter aircraft had a better all-round performance than the Ki-84. As far as protection goes, the Ki-84 had seat back and head armour of 12 mm steel, and self-sealing fuel tanks. The self-sealing tanks were not considered as efficient as those fitted to American aircraft at the time. [/I]

The Ki-84 was not clearly superior to any of the Allied fighter aircraft opposing it. In perfect running order it was perhaps the equal of any allied fighter at 20,000 feet or below. A good pilot would be able to take advantage of its excellent turning, climbing and acceleration characteristics to at least give an allied opponent a hard fight.

Hopefully once we get a patch on the power issues we'll see a plane that comes closer to this....
« Last Edit: November 01, 2004, 12:01:09 PM by humble »

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Offline Charon

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ki84 speed????
« Reply #37 on: November 01, 2004, 11:59:26 AM »
The SL speed for this variant is 324. The WF variant is 363 (from what I can find). That's 39 mph, unless the figures I came across are 20 mph too high. I would expect a reasonable RL performance (if those figures are accurate) to be around 340-350 SL with lower octane fuel, etc.

Maybe I'm wrong, but some of the fuel octane threads I've seen in the aircraft forum lead me to believe octane only gets you so much.

[edit: I though you were disagreeing with the 40 mph difference Karnak, I think you were just pointing out the logical 20 mph RL difference you could expect.]

Charon
« Last Edit: November 01, 2004, 12:07:45 PM by Charon »

Offline Karnak

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ki84 speed????
« Reply #38 on: November 01, 2004, 12:09:18 PM »
At 324mph at SL and 388mph at best altitude the AH Ki-84 seems to be directly modeled on the first prototype.

The first prototype was powered by an Ha-45-11 engine, which was less powerful than the Ha-45-21 engine that powered the production model.

The first prototype lacked the ejector exhaust stubs that were introduced in the preproduction aircraft and were present in the production aircraft.

The production models were cleaned up areodynamically when compared to the first prototypes.

The third prototype did 392mph at best altitude and it too lacked most of the production changes.


As it stands, based on what I know of the Ki-84, the AH Ki-84 would be semiappropriate as a 1943 Ki-84 used in service trials, not a 1944 service Ki-84.
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Offline humble

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ki84 speed????
« Reply #39 on: November 01, 2004, 12:17:46 PM »
I'm more confused by the handling than the speed issues. Normally even in a Ki-61 or similiar plane I'm almost never flying at full power during a fight. So I was awful suprised how quickly it ran out of smash in what should of been a very favorable set up for it. Guess I'll fool with it a bit more tonight...but realistically probably just go hunt 84's in my 61:aok

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Offline GRUNHERZ

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ki84 speed????
« Reply #40 on: November 01, 2004, 12:17:51 PM »
I am kinda surprised about the coice to model the Ki84 at 324/388 since it seems that it has been demonstarated on this board that this was the performonce of a rough and unfinished  prototype with a weaker engine and lacking some important gear like the speed enhancing ejector exhausts.

So from my view we have two hard data sets that probably set the boundaries but are IMO most likely not fully representative of in-service planes.

324/388 for the rough first development prototype.

and

363/427 for a well treated/pampered production plane with US 100 octane fuel fuel.
 
I'm curious why was the low figure chosen? Why not shoot for a happy medium?

Also what of this mention of MW50? Did Ki84 mount this system? Would the 100 octane gas approximate the anti detonation properties of low octane gas and MW50 running at higher boost?
« Last Edit: November 01, 2004, 12:20:46 PM by GRUNHERZ »

Offline Montezuma

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ki84 speed????
« Reply #41 on: November 01, 2004, 12:21:57 PM »
Quote
Originally posted by humble
Guess I'll fool with it a bit more tonight...but realistically probably just go hunt 84's in my 61:aok


Been playing around with the Frank, it will easily beat the Tony in the vert.

Offline Karnak

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ki84 speed????
« Reply #42 on: November 01, 2004, 12:25:49 PM »
Quote
Originally posted by Montezuma
Been playing around with the Frank, it will easily beat the Tony in the vert.

And the Tony is absolute crap in the verticle as modeled in AH2.

I'm not happy.
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Offline humble

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ki84 speed????
« Reply #43 on: November 01, 2004, 12:37:54 PM »
Quote
Originally posted by Montezuma
Been playing around with the Frank, it will easily beat the Tony in the vert.


Not a chance in the world....

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Offline TBolt A-10

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ki84 speed????
« Reply #44 on: November 01, 2004, 12:48:41 PM »
Guys,
wait for the patch...let's see how the plane flies after the fix.

But, look at it this way...

...this is the first version of the Hayate.  perhaps, HTC could find it in their kind hearts to add a second variant with a little more balls.  :)

I, too, was expecting more of a rocket.

I was also expecting it to break apart in a high-speed dive, & we got that!  :lol   Elevators blew right off (didn't notice the speed, but it was fast).
« Last Edit: November 01, 2004, 12:53:24 PM by TBolt A-10 »