German Prop Pitch Lever

[heloguy]

Originally Posted by Blackdog_kt

On the other hand, it could also be that the detent enables an extended range of motion that's not available via the normal control range to prevent accidental feathering in flight.

That may be true, but I'd almost go as far to bet that this was an analog switch that worked on resistance: the further you moved the switch away from center, the faster the prop adjusted up to the max, which was around .7 degrees per Kurfurt's note. This was simple enough back then, as there's no special pressure sensing, it would just be an increase and decrease in electrical resistance.


Edit: Changed the prop change speed after reading Kurfurst's post better.

[Kurfürst]

Originally Posted by heloguy

-.....he faster the prop adjusted up to the max, which was around .7 degrees per Kurfurt's note. This was simple enough back then, as there's no special pressure sensing, it would just be an increase and decrease in electrical resistance.

Keep well in mind that the French report above is based on an assumption:

"assuming that the speed of the rotation of the electric motor to be 2500 rpm..."

then, IF this is TRUE

"the speed of change of the pitch would be of the order of 0,7 degrees per second"

Keywords: "assuming" "would be" "of the order of".

I presume the assumption by the French simply follows the gear ratios found, ie. IF the e-motor runs at 2500, THEN the prop pitch change will be 0.7 degrees/sec."

HOWEVER the speed of the rotation of the electric motor (VDM Elektrischer Drehzahlregler 9-9518B type) appears to be 5700 /min, and NOT 2500 /min as the French assumed. Ie. a bit more than TWICE as fast.

See: D.Luft. T 3810 VDM Verstellscharuben Geraete Handbuch, page 19, page 29:




Based on the above, assuming about 1,5 degrees/sec for the 109E seems entirely reasonable. After all, that's about what every single source tells us, including Schwarze Mann. And it was so before in the patch..

[IvanK]

A little more from Schwarze-mann



So in Static conditions 1.5 deg sec and in normal (under load) conditions 1 deg per sec. so in flight imo we should be seeing 1 deg sec pitch rate. This is consistent with all the references shown in this thread.

Devs are aware of this issue expect a fix soon.

[VO101_Tom]

Originally Posted by IvanK

A little more from Schwarze-mann

http://img861.imageshack.us/img861/638/dbbmpropitch.jpg

So in Static conditions 1.5 deg sec and in normal (under load) conditions 1 deg per sec. so in flight imo we should be seeing 1 deg sec pitch rate. This is consistent with all the references shown in this thread.

Devs are aware of this issue expect a fix soon.

Great. Thank you.
I was thinking about something meanwhile. It reports it if the velocity of the elektromotor changes (Kurfurst doc: PP motor 2000-6000 rpm), that with the switch can be made change in? slow or fast moving it depends, how much I drive the switch out from middle?

[edit] No. I found the circuit diagram [1] [2], its only a simple switch. PP have constant speed.
Ok ok, i'm finished