Author Topic: true FW190 rollrate (Read 2915 times)

J_A_B · « **Reply #30 on:** June 20, 2002, 12:31:50 PM »

Perhaps the Naca 190 DID have heavier controls than a usual FW-190.

What needs to be answered, is if those controls were so unusually heavy that they interfered with the plane's roll rate. If the pilot of the NACA 190 could still deflect his ailerons as far as any other 190 pilot could, then the heavier stick forces meant nothing in terms of maximum roll rate (in combat of course would have been a different matter completely).

J_A_B

RRAM · « **Reply #31 on:** June 20, 2002, 12:34:28 PM »

Quote

Originally posted by J_A_B
Perhaps the Naca 190 DID have heavier controls than a usual FW-190.

What needs to be answered, is if those controls were so unusually heavy that they interfered with the plane's roll rate. If the pilot of the NACA 190 could still deflect his ailerons as far as any other 190 pilot could, then the heavier stick forces meant nothing in terms of maximum roll rate (in combat of course would have been a different matter completely).

J_A_B

JAB, if you're testing the rollrate of a plane at a given force applied on the stick at a given speed...you BET that, if the plane is unusually heavier of controls, the results are going to be seriously corrupt.

And if those tests are done at high speeds (where stick forces are stronger), the results are going to be even more corrupt.

If that particular 190 had heavy controls, yes, that chart would be completely off-the mark.

AKSWulfe · « **Reply #32 on:** June 20, 2002, 12:44:10 PM »

Okay, I got it now.

Was just wondering where they got that 18deg from.
-SW

J_A_B · « **Reply #33 on:** June 20, 2002, 12:49:02 PM »

From what I understood, regular FW-190's would never reach 50 pounds stickforce at lower speeds.

Which means if the "porked" FW-190 in the NACA tests reached that 50 pound mark at or near full deflection, there wouldn't have been a noticable difference.

Plus, how much of a difference is "signifigantly" heaver? 1 pound? 10 pounds? In a plane like the 190 with very low stick forces, a 1 pound difference may well be considered signifigant--yet really wouldn't be.

BTW, I agree with you that the AH 190A5/8 is a bit too slow and maybe rolls a bit too poorly. I just don't necessarily think that the possibly heavy controls of the NACA 190 made any real difference. Maybe it did, maybe it didn't.

J_A_B

RRAM · « **Reply #34 on:** June 20, 2002, 12:58:00 PM »

Quote

Originally posted by J_A_B
From what I understood, regular FW-190's would never reach 50 pounds stickforce at lower speeds.

define "lower speeds"...

in any case , JAB, at 250mph IAS, the pilot was already pulling 50 pounds of pressure according to that chart. That is the point where the all-increasing rollrate stops increasing and starts decreasing dramatically due to the need to keep 50lbs on the stick

Is that "light controls" at a "lower speed" for you?

Quote

Which means if the "porked" FW-190 in the NACA tests reached that 50 pound mark at or near full deflection, there wouldn't have been a noticable difference.

according to the NACA chart, that 190 reaches those 50pounds at 250mph IAS, what it doesn't mean is that is at full deflection at that point.

Someone does know the REAL aileron deflection in a 190 ,please?

Quote

Plus, how much of a difference is "signifigantly" heaver? 1 pound? 10 pounds? In a plane like the 190 with very low stick forces, a 1 pound difference may well be considered signifigant--yet really wouldn't be.

BTW, I agree with you that the AH 190A5/8 is a bit too slow and maybe rolls a bit too poorly. I just don't necessarily think that the possibly heavy controls of the NACA 190 made any real difference. Maybe it did, maybe it didn't.

J_A_B

Yep, that's the only problem here...that we don't have REAL idea on how "hard" was the plane on the controls. Just the reports from the tests pilots...but I guess that a coulpe of pounds of difference wont be exactly make a test pilot remark the "hard controls" in a certain plane compared with another....don't you think?

Furious · « **Reply #35 on:** June 20, 2002, 01:16:12 PM »

Heinkel,

I am a LW fan and I asked the same questions.

The information described in this chart, if it's correct, is not very usefull without more data.

Be skeptical.

F.

edit: whoa huge reply lag

J_A_B · « **Reply #36 on:** June 20, 2002, 01:16:16 PM »

"but I guess that a coulpe of pounds of difference wont be exactly make a test pilot remark the "hard controls" in a certain plane compared with another"

Depends on the situation. Take 10 FW-190's. 9 have normal super light controls, the tenth is a pound heavier.....that last one will stick out like a sore thumb to a pilot used to flying the others despite still being a light plane overall.

OTOH it's equally possible that in this particular 190 maybe the control rods were bent or something and it flew like a brick. We just don't know.

J_A_B

MANDOBLE · « **Reply #37 on:** June 20, 2002, 01:19:20 PM »

-ammo-, why scandalous? Easy to answer ...

Here is me doing 250mph while rolling:

How many deflection degrees do you see at the aileron? About 35, right?
Ok, acording to the chart for 250 mph I should have been doing about 332 degrees per second. 9.5 dps per deflection degree for 250 mph with 35 deflection degrees = 332.5 dps.

Hristo · « **Reply #38 on:** June 20, 2002, 02:40:26 PM »

Again, no words from HTC staff.

AKSWulfe · « **Reply #39 on:** June 20, 2002, 02:44:06 PM »

and you just guaranteed they won't respond Hristo.
-SW

niklas · « **Reply #40 on:** June 20, 2002, 03:08:28 PM »

Hi

The chart is from a report from M. B. Morgan and R. Smelt. I only have 1 page, but their names are given in the header.

It´s from the RAF, and not from german source. So no exaggeration took place!

It was me who added the 18° mark, because knowing rollrate/degree deflection is useless without knowing the maximum possible deflection. 10/s *18°= 180°/s, what you already found out.

I remember 18° up down from a fw190 handbook where i was able to have a look into when i visited FLugwerk. Those are no unusual deflection ranges, even the somewhat limited P51 still had 10°. The 109 deflected 22° up and 12 ° down. A P39 25° up and 10° down. If you sum them up you reach in every example around 35° deflection total.
Btw the Ta152 used the same deflections, 18° up and down, and here i have the data.

The captured english report of the A3 mentions 17° up and down - ok, 1 degree less, but the aileron design changed at least 3 times and maybe they added 1 degree later. It would still be ~190°/sec
You can read it here, page 2 right below the flap picture:
http://mitglied.lycos.de/luftwaffe1/flight/fw190a3/flight_fw190a3.html

Cpt Eric Brown: incredible aileron turns were possible....

this is all what the RAF found out, and i think the english didn´t had reasons to make the germans look better than they actually were...

niklas

RRAM · « **Reply #41 on:** June 20, 2002, 03:12:15 PM »

Heya niklas, thanks for sharing that info

I assume there is no information at all about the stick forces involved in the process of testing the plane...wich is something sad given the current state of affairs (if you got a chart, you get nothing , si if you don't, go figure, hehehe

)

Does the report talk especifically about light controls at high speeds too?. If it does then we might be on something really neat here, maybe not for AH, but at least for better knowing the 190

.

AKSWulfe · « **Reply #42 on:** June 20, 2002, 03:12:49 PM »

Is 18degrees the max deflection at all speeds? How is that possible?

I'd think it would be damn near impossible to get it to 18degrees at 400MPH... but then again, I dunno.
-SW

Dux · « **Reply #43 on:** June 20, 2002, 03:34:15 PM »

Not taking sides, and not knowing anything about anything...
I find it hard to believe that "deg/sec/deg of deflection" is a purely linear function. I would think that may be an optimum roll rate, but it would trail off at very slight or very extreme deflections. I mean, do the math for a 150-degree deflection at whatever speed... the formula would give you an extremely fast roll, but logic tells you that, at this point, you no longer have an aileron, but instead an airbrake. Yes I know this is a ridiculous example, but I think it makes my point about it being a nonlinear function.

senna · « **Reply #44 on:** June 20, 2002, 04:50:58 PM »

I beieve that graph assumes that you can plug in 18 degrees of aileron deflection throughout its range of values. That would make sense. Even pluging in the 18 degrees of max deflection where it was not possible (due to stick forces or aerodynamic forces) should be compensated for in the graph. After all, you cant fly into then graph what is not possible. Right?