Aces High Bulletin Board
General Forums => Aircraft and Vehicles => Topic started by: 1K3 on December 10, 2004, 07:24:23 PM
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Made flight model changes to the Ki-84. Mainly, a lowering of climb rate at military power and the addition of a short amount of overboost capability.
does it still have the "1943 test trial" speeds?
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Ok, here’s what I got testing the Ki-84 this morning:
Speed on deck, no WEP: 327 mph
Speed on deck with WEP: 348 mph
Speed at 22,500 ft without WEP: 382 mph
Speed at 22,500 ft with WEP: 388 mph
Climb: 25% gas; from a standing start on runway to 5,000 ft: 87 seconds. For comparison, I did the same test with an La-7 with 50% gas in its tanks (about equal duration to Ki84 with 25% gas). The La-7 took 86 seconds to reach 5,000 feet. A virtual dead heat.
WEP duration: About 90 seconds
Cool down to normal temperature: About 30 seconds
So, you have a WEP duty cycle of 90 seconds on, 30 seconds off, 90 seconds on and so on.
Elevators seem lighter than before patch, but that may just be my own perception.
Conclusions: The Ki-84 is even deadlier than before. It can run away from any of the other turn fighters with ease. Especially when we factor in acceleration.
Yup, the revised Ki-84 accelerates much faster than the previous edition.
I did my standard acceleration test: level at 200 feet, power adjusted to speed is stable at 200 mph. Go to full power and engage WEP, record time required to reach 300 mph.
You may remember that the previous Ki-84 accelerated dead even with the Spitfire Mk.V. Well, that's changed dramatically.
Times from 200 mph to 300 mph:
La-7: 28 seconds
Ki-84: 29 seconds
Spit V: 51 seconds
With these numbers, the Ki-84 just moved higher up the uber scale.
My regards,
Widewing
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Widewing what did you use to measure the speeds? I used the E6B and couldn't get above 342mph with overboost, 324mph full military. Wonder if alt is a factor here, I went as low as possible (around 20ft ASL)
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Originally posted by Kaz
Widewing what did you use to measure the speeds? I used the E6B and couldn't get above 342mph with overboost, 324mph full military. Wonder if alt is a factor here, I went as low as possible (around 20ft ASL)
How much fuel were you carrying? Hammer's testing showed that fuel load has a significant effect on speed. I was flying with 25%, zero burn rate.
It seems that the limiting factor here is WEP duration. Try this: Climb to 2k, dive down to 200 feet (in MIL power). Let your speed degrade down to 360 mph. Engage WEP. You will see that the airplane will sustain 347/348 mph until it runs out of WEP. When accelerating to max speed, you will run out of WEP before you can get there. I can't get better than 344 this way. In terms of actual usage in the MA, I can't think of many instances where I would not be diving to the deck in pursuit of an enemy.
So, let's amend max speed on the deck to say that depending upon various factors (fuel load, ammo load, etc), it may vary between 342 and 348 mph.
Using acceleration from 200 mph, I saw 324 mph at MIL power, 344 mph when the WEP quit. Decelerating from 360 mph, I saw 347/348 with WEP and down to 326 sustained in MIL (it takes miles to lose just 1 mph) for 3 minutes. Longer runs may result in additional speed loss. I only tested for 3 minutes.
Either way, the Ki-84 is at least 20 mph faster on the deck than before, and that is significant.
My regards,
Widewing
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343mph in my test. (Sea Level @ 20ft)
Anyway, the updated Ki-84 holds much better Es on the deck.
BTW thanks for reporting accel test, Widewing.
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That explains it then I was using 100% fuel. Thanks for the explanation.
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Originally posted by Kaz
That explains it then I was using 100% fuel. Thanks for the explanation.
The speed you quoted is correct, within 1mph for a fuel load of 25%. Others have posted values 1mph faster than you, and which of the two readings you get depends on how you carry out the test, the true value is somewhere in-between the two.
Widwing's value is higher than the correct value. You can confirm this with a high degree of repeatability and consistency, if you re-fly the tests. But don’t forget that acceleration/deceleration is very slow close to the top speed, and the wep duration is only short, so don’t start too far away from the anticipated value or you won’t have time to get there before the wep runs out, as Widwing pointed out.
Also, the fuel load only makes a small difference to the top speed. With a full tank, you would only expect the speed to drop slightly, perhaps 3mph or less depending on the fuel quantities involved. You can also confirm that with good consistency by similar tests.
Hope that helps…
Badboy
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I get 343mph at 20ft and 344mph at 200ft with 25% fuel.
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I can confirm that Karnak and Mitsu's values are correct.
Badboy
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Originally posted by Karnak
I get 343mph at 20ft and 344mph at 200ft with 25% fuel.
I get the same numbers accelerating to speed. A bit higher coming down over 3 minutes. But if you wait long enough, it does drop down to 344 at 200 feet.
My regards,
Widewing
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my figures were near same, posted in the
Patch 5 thread in General Discussion (http://www.hitechcreations.com/forums/showthread.php?s=&threadid=137536&pagenumber=2)
I came up with 1min 30 to 31 secs WEP with a 46 to 47 sec cool down period timed 10 out 10 times.....
my top speeds were based on E6B and after attaining top military speed I tested wep with top speed of WEP at time it shut off.....
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Widewing,
I have always used the deceleration method of speed testing ever since I did speed tests in AH.
To get the 343mph and 344mph numbers what I did is wait until the speed drops to 350mph and then turn on WEP. Once the WEP expired I look at the speed.
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Originally posted by Karnak
Widewing,
I have always used the deceleration method of speed testing ever since I did speed tests in AH.
To get the 343mph and 344mph numbers what I did is wait until the speed drops to 350mph and then turn on WEP. Once the WEP expired I look at the speed.
You can still reach 344 mph, just don't engage WEP until you stabilize at 323 mph. However, not long after, you run out of WEP.
My regards,
Widewing
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Originally posted by Karnak
I have always used the deceleration method of speed testing ever since I did speed tests in AH.
Karnak,
I use the deceleration method for Military power, I dive for excess speed then let it stabilize, then once it stops dropping I wait 10 minutes, then I turn on WEP and note speed as soon as wep runs out.
for timing WEP operational use and cool down time, I do it on an average of 10. I time its use and cool down 10 times then total them and divide by 10 to get my average, speeds I usually just take avarage of 3, but most times all 3 are indentical....
most people will not be diving and then turning WEP on, they will be wepping thru out the whole fight or chase from the start, this is my reason for recording wep speed the way I do...not that it really matters.......
but: this Ki-84 goes a good ways before it starts to decelerate!
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TequilaChaser,
Actually I test it the way I do for the same reason. We just reached oposite conclusions.
I test for terms of diving to the deck and pusuing, or running. In either case the aircraft will almost certainly be well over it's sustainable speed, so I am more interested in watching it's deceleration to it's sustained WEP and MIL speeds. Very rarely do I find myself on the deck using WEP to try to accelerate to top deck speed. I cannot, in fact, think of an occasion when I've ever done so.
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Ok then, quick questions -->
1) Why does Kenneth Munson (Fighters and Bombers of WW2, Peerage, p.46) list the max speed of the Ki-841a as 427mph at 20,000 ft? [via US post war testing].
Surely they can't be that far off (almost 40mph)?
BTW - The lowest figure that I've seen for the KI-841a is 392 mph, why is ours 4 mph slower than that?
2) Correct me if I'm off base here, but our N1K1 still seems like a better performer, in terms of max speed, accel, and turn.
- SEAGOON
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Originally posted by Seagoon
2) Correct me if I'm off base here, but our N1K1 still seems like a better performer, in terms of max speed, accel, and turn.
- SEAGOON
actually it is a N1K2-J that we have, also it is far less superior than the Ki-84-Ia we have, it is slower, it climbs slower and accels slower all around slow! turnrate prob real close though, soon you prob have something or someone to verify this :-)
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Originally posted by Seagoon
2) Correct me if I'm off base here, but our N1K1 still seems like a better performer, in terms of max speed, accel, and turn.
- SEAGOON
I don't think so.
Actually the Ki-84 is better at these performances than N1K2-J:
1) Speed.
2) Acceleration.
3) Initial Climb rate.
4) Roll rate.
5) Maneuverability especially slow speed. (I think Ki out-turns N1K in overall though).
6) Handling ability at low-medium speed.
The N1K2-J is better at few things than Ki-84:
1) Firepower.
2) Maneuverability at high speed.
3) Dive performance.
The weak point of Ki-84 is high speed dive performance and firepower, I think. Currently the Ki-84 is best fighter for me excepting it.
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Cockpit visibility is also better in the Ki-84.
The firepower in the Ki-84 is less than the N1K2-J, but it is still more than adequate for taking on anything other than the big Allied bombers and even there it can get the job done.
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Mitsu and I tesated Ki84 vs Niki and found out that Ki84 dominates in 1 vs 1..
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I can't be the only one feeling that the Niki got changed for the worse in AH2.
I used to absolutely love that plane in AH1... I'd take off and land like 15 kill sorties in it.
AH2 niki just feels "different"... feels like it rolls slower and doesn't turn as well as it used to.
And by the way... I'll vouch for a Ki-84 dominating a Niki.
Ki-84 is about an even fight with a Spit 9, the Ki is better at low speed manuvering (like <150 mph), the Spit 9 is better above it. Spit 9 has far more firepower, so if it gets a quick snapshot it'll probably win the fight.. if not it'll get worn down.
The Niki used to be about even with the Spit 9 (a little better in my opinion), now it isn't even close to as good, at least in my opinion.
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The first and foremost changes in the N1K2 is in the reduced roll rate - especially at high speeds.
I'm not sure if I remember it correctly, but I believe it now takes about more than 8 seconds for a full 360 roll at 400mph. In AH1 it was certainly not the best of performers at high speeds, but it was at least average.
Another hit was an indirect one - the changes in gunnery negated most of the 500yard+ shots that used to happen so frequently in AH1. Couple that with a wing-armament of cannons and the long-range hit capability of the N1K2 probably dropped more than 50% in efficiency, despite the huge ammo load to spray with.
This was a pretty much devastating blow to most N1K2 pilots in AH1 - their favorite tactics used to be the "mow down".
They'd climb up to 15k+, and use the alt advantage to sweep down the "layers" of altitudes one by one, using short "bursts" of speed by steep dives. With this speed they'd momentarily catch up to a faster plane within 500 yards and then start shooting.
Since the AH1 N1K2 could handle most speeds comfortably, it was very difficult to escape from a N1K2 that was fast and diving. It'd stay with most planes in dives, and keep shooting.
Since the guns hit further out, in a speedy chase a defensive jinking would easily elongate the flightpath of the chased plane, and the distant just wouldn't part. The N1K2 would be latched on firmly.
If the jinking was only slight, you'd get hit by the guns at 400~600yards distance. If the jinking was too hard, or you went into defensive maneuvering, you'd be outmaneuvered and get shot down also.
By the time the N1K2 reached deck altitude it probably would have scored about 4~5 kills at least.
However, all that's changed in AH2. A high speed chase of over 350mph and even a 109 would just roll 180 degrees and get out of the way, and the N1K2 can't follow. It just rolls too slow, even with rudder assist.
Also, a steady increase in speed and distance of over 400 yards, and a slight jinking would suffice. I've had quite many experience escaping from guys like wingzero or busa or kyle, from that 400yd distance, in AH2. I might lose a part or two, but I'd live. Were it in AH1 there would be no way I'd be able to escape that situation.
Ofcourse, needless to say the same tactic also worked for the Spit9s in AH1, which, doesn't work anymore on AH2. I'm not sure why the usage numbers are still so high for the N1K2 or the Spit9, but empirically, I've been seeing them in AH2, about half of what I used to in AH1. There just isn't Spitfires or N1K2s around anymore in AH2 (with the exception of the last-minute base defense planes, or CV based Seafires).
Also, the changes in FM effected the N1K2 and Spit9, too.
In AH1 these two planes were among the most stable. As a matter of fact, in AH1 "better turning" usually also meant "better stability" in harsh maneuvering. You could just yank the stick around with some speed and they'd pull great instantaneous turns, giving out gun solution most of the times.
Things just don't happen that way in AH2. In many cases some planes would have great sustained turn performance, but not instantaneous turn performance.
In AH1, if I was in a N1K2 or a Spit5 or 9, and I'd see a target in front of me which I almost have lead on, I could just chop throttle down, kick rudder full, momentarily yank the stick hard and would get a firing solution. Fire the shot, relieve the pressure, and the plane would be still flying. If I do that in AH2 the plane will stall out.
So, some pretty heavy changes in small details I'd say. The Ki-84-Ia IMO is superior in almost everything over the N1K2, including maneuverability.