Ki-61 strangeness?

[ispar]

I already posted this, but decided that the title should perhaps be something more likely to call attention to this.

The Ki-61 seems a little strange. On a whim, I decided to test it's vertical performance and stall characteristics.
From low alt, about 500 feet, I pulled into a vertical climb. Airspeed dropped off steadily as I got higher. As I was correcting for torque roll toward the top of the climb, I glanced at the speedometer to estimate about when the plane should flop over. It read 50 mph!  STILL the plane went up until it reached zero mph. What it did next was even more amazing. It started to descend backwards! As it did so, it rolled gently to the left. The nose dropped slowly and gently as this occurred. When it dropped about 15-20 degrees below the horizon, the rolling stopped easily. No stall. Not even a stall HORN. Not a spin. A tail slide with rotation mixed in, with nary a care from the Tony. I pulled her out of the dive with my jaw hanging open.

Needless to say, I started recording immediately and performed the maneuver several times. It is important to note that WEP was on, but I believe that I may have done it once when WEP ran out.

Whether it's correct or not, this is WEIRD. You'd have to see the film to get a better idea. Anyone willing to post it for me?

Whether this is an FM bug or not, I think it's best to nip questions about it in the bud before people start whining about the "helitony."

The Ki-61c Tony - the other N1K?

BTW... no, I was not hunting for quirks, I was simply curious. And what a surprise I got!


------------------
"E's bound to be guilty, or 'e wouldn't be 'ere!
Starboard gun! FIRE!
Shootings to good for 'im, kick the louse out!
Port gun! FIRE!"
- Old chant used to time saluting of guns on ships

[flakbait]

I've seen the same thing. I think both the Ki-61 and the Il-2 have a slight glitch in wing lift. I got the Ki-61 off the ground at about 80mph with just 2 notches of flaps. Il-2 popped off at 100mph fully loaded with 2 notches as well. No stall horn, no screaming in my ear, nothing. Maybe the N1K2 wing-lift bug hit these aircraft as well?


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Flakbait [Delta6]
Delta Six's Flight School
Put the P-61B in Aces High
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb
 

[Naudet]

flakbait, for the IL2 i would say this is quit normal, it was build for groundpounding and low speed capability.

That was one reason why it was such a hard kill for GE fighters, it could deaccelerate below the stall speed of the 109ers and still turn pretty good.

And 80 mph with 2 notches of flaps seems not so weird, dunno if the 2 notches already give the KI61 full flaps or half flaps. But i think it has pretty large wings for such a small and tiny fuselage.

But this climbing issue really seems a bit off.

[juzz]

"Wing-lift" bug, a.k.a. low wingloading...

Spitfire IX: 30.15lbs/ft^2
Ki-61: 30.21lbs/ft^2
Il-2 Type 3(at max weight!): 33.78lb/ft^2, without bombs: ~30lbs/ft^2 or even less...

[MiG Eater]

Holding a steady rate climb at 100 mph in the Ki-61, I was able to induce the stall horn if I attempted to pull into a climbing turn.  I found the only time the stall horn didn't sound was if the airplane was purely vertical with the wings producing no lift.  This seems normal since you should only get a stall warning when you exceed a certain angle of attack.  In the pure vertical, the angle of attack is close to or at 0° since the wings aren't producing lift.

Its one heck of a turner though!

MiG

[ispar]

 

Originally posted by MiG Eater:
Holding a steady rate climb at 100 mph in the Ki-61, I was able to induce the stall horn if I attempted to pull into a climbing turn.  I found the only time the stall horn didn't sound was if the airplane was purely vertical with the wings producing no lift.  This seems normal since you should only get a stall warning when you exceed a certain angle of attack.  In the pure vertical, the angle of attack is close to or at 0° since the wings aren't producing lift.

Its one heck of a turner though!

MiG

Yes, that's correct. However, the plane still does not seem to stall, and certainly doesn't spin. Have you taken vertical far enough to get the helicopter descent? Can anyone post the film?

------------------
"E's bound to be guilty, or 'e wouldn't be 'ere!
Starboard gun! FIRE!
Shootings to good for 'im, kick the louse out!
Port gun! FIRE!"
- Old chant used to time saluting of guns on ships

[funked]

Geez some guys never been to an airshow?

[ispar]

 

Originally posted by funked:
Geez some guys never been to an airshow?

No... I would not be concerned except that I have never been able to do this with any other plane in AH. I simply do not know whether this is correct or not. It feels too easy, considering that I can't manage it otherwise. I'd appreciate a note from Pyro or Hitech about this. Simply for clarification, I have no intention of complaining about the fine work they have done with this sim.

------------------
"E's bound to be guilty, or 'e wouldn't be 'ere!
Starboard gun! FIRE!
Shootings to good for 'im, kick the louse out!
Port gun! FIRE!"
- Old chant used to time saluting of guns on ships

[Tac]

man Ki61 is SCARY in low speed fights, it can pull some amazing things.

Thank heavens it wasnt assimilated by the aliens. The plane does have its weaknesses (crappy accel, bleeds E and bad rear visibility).

[GunnerCAF]

 

Originally posted by ispar:
...However, the plane still does not seem to stall, and certainly doesn't spin. ...

I had no problems putting the KI 61 into a spin.  I dropped at least 15K before I could get the nose down and pull out.  I was not trying to hang on the prop, but it will spin  

Gunner <CAF>
GunrCAF

[flakbait]

Here's a wing-loading comparison taken using loaded weights:

Ki-61: 35.53 lbs/ square foot
A6M5b: 26.38
Ta-152 H1: 41.75
P-47 D25: 48.667
P-51B: 39.48


I still say the 1.07 aircraft have a wing lift bug. Getting a max loaded Ki-61 off the dirt with 2 notches flaps (4 notches available) at 100mph is nuts. We can't even do this with the F6F, and it got airborne at 85mph, loaded, with full flaps! I had no idea that 4 lbs/sq.ft difference between the P-51B and the Ki-61 would make the Ki-61 turn like an N1K2.


-----------------------
Flakbait [Delta6]
Delta Six's Flight School
Put the P-61B in Aces High
"For yay did the sky darken, and split open and spew forth fire, and
through the smoke rode the Four Wurgers of the Apocalypse.
And on their canopies was tattooed the number of the Beast, and the
number was 190." Jedi, Verse Five, Capter Two, The Book of Dweeb
 

[Fishu]

 

Originally posted by funked:
Geez some guys never been to an airshow?

Do you mean we should model these WW2 shooter planes into those aerobatic champs?  

I've seen them going sideways and even climbing that way...
Which should hardly be possible with WW2 fighters.
(we had once those planes even Ju-88 could of done it)

 

[juzz]

 

Originally posted by flakbait:
Here's a wing-loading comparison taken using loaded weights:

Ki-61: 35.53 lbs/ square foot
A6M5b: 26.38
Ta-152 H1: 41.75
P-47 D25: 48.667
P-51B: 39.48

I still say the 1.07 aircraft have a wing lift bug. Getting a max loaded Ki-61 off the dirt with 2 notches flaps (4 notches available) at 100mph is nuts. We can't even do this with the F6F, and it got airborne at 85mph, loaded, with full flaps! I had no idea that 4 lbs/sq.ft difference between the P-51B and the Ki-61 would make the Ki-61 turn like an N1K2.

1. Ki-61-KAIc with 2x550lb bombs gives that wingloading. Without bombs it is 30.42.

2. P-51B-1-NA loaded weight was 9,200lbs - but in AH we have the P-51B-5-NA, which would weight 9,800lbs = 42.06

3. F6F-5 with 2x1000lb + 6x5", wingloading = 45.81

4. N1K2-J wingloading at normal loaded weight = 34.85

PS: 60,000lb Lancaster got up at 90mph IAS in RL... try that one in AH!

[gospel]

I noticed that the KI61 does seem to "fly strange" at low speeds in a climb.  90 mph, nose up attitude, 2 notches of flaps, 100% throttle, and it gains 2000 fpm.

I was expecting the plane to compress much more in a dive too.  It does not seem to compress much at all   .

 

[This message has been edited by gospel (edited 05-26-2001).]

[ispar]

Well, regardless, I found something interesting about the Ki-61. Call me unskilled, but it's te only plane in AH which I have managed a flat spin in. Climb vertically, when the speed goes through 100, chop the throttle. Great fun, but I haven't figured out how to recover. Full flaps and few thousand feet should do it thouhg, I think  .

------------------
"E's bound to be guilty, or 'e wouldn't be 'ere!
Starboard gun! FIRE!
Shootings to good for 'im, kick the louse out!
Port gun! FIRE!"
- Old chant used to time saluting of guns on ships