flight dynamics problems

[bstolle]

1. I don't know what is yaw stability means.
2. I guess you are referring to directional(vertical) dynamic stability.
3. It could positive, negative, neutral. For example if after pressing and releasing the rudder after few oscillation an airplane returns to equilibrium (initial state) it means it has positive dynamic vertical stability.I believe Me-108 exhibit positive vertical dynamic stability.
4. While I agree video may provide some interesting information, without the "numbers" it's very hard to determine actual airplane behavior.
5. Most so called tricycle gear airplanes ( those without tailwheel aka taildragger ) are actually have steerable nose wheel.
The steering is coupled with the rudder pedals therefore when pilot steers the rudder moves as well. Slipstream does not control the rudder - pilot does.
6. It doesn't matter if airplane heavy or light if it has propeller on front of it it will be affected by toque, hygroscopic precession, slip stream and P-factor.
When critical angle of attack is reached one wing could stall earlier than another. The reason for that could be an engine torque, a wind gust, weight and balance and etc.
7. Aft CG doesn't necessarily mean CG beyond aft limit. For example, P-39 by design had aft CG and therefore had particular flight characteristics
By the way, a lot of modern airplanes today have aft CG among others MD-80s, CRJ, F-15 and etc.

1. ok
2. no
3. that's exactly the point. This Bf108 doesn't oscillate a single time that's why I mentioned that the yaw stability (or damping) might be too high
4. If you have active Bf108 pilots it would be no problem to determine the actual behaviour.
5. You are comparing apples and oranges. We were talking about taildraggers without any steering and now you are talking about tricyle gear gear config with nosewheel steering????
There's absolutely no way you can compare these two!
7. If you know how much the prop of the 108 weighs do you really think that this prop at idling RPM has any significant influence on the stall behaviour?
The argument concerning W&B and 'wind gusts' is definitely out of place in this discussion
8. Another apples & oranges comparison. You are not seriously comparing a well designed almost foolproof GA plane with a high performance WWII fighter.
The target design in flight behaviour is rather different
9. And another weird argument. Neither the CRJ or the MD-80 series has an 'aft' CG. Exactly the opposite is the case with e.g. the MD80 series.
Especially the MD87 is so nose heavy that most airlines have to leave the forward cargo compartment empty!
BTW, in 10 years of flying the CRJ I never noticed that we had an 'aft CG'.

I mentioned the problems with the initial flight dynamics, the error has been found and corrected, so I consider a further discussion about these points rather useless.

[Mathias Pommerien]

There's another little patch forthcoming that will improve slat interaction/low speed handling and the somewhat too high roll on rudder input.
Should then lay all discussions regarding the flyight dynamics to rest, I suppose.

[Ebo]

Thanks Mathias for all your efforts in making us customers happy.

I love this great plane!

[Mathias Pommerien]

4. If you have active Bf108 pilots it would be no problem to determine the actual behaviour.
.

We have four of this rare breed (4) along with all data that has been test-flown with D-EBFW, both with the fixed prop and the variable pitch prop.
None has bugged a fundamental missbehaviour with the flight dynamics but agreed that it has an impressively natural feel to it, just like the experience it in real life.

[bstolle]

perfect, thanx