If you experience the "prop pitch bug" in the 109E4

[IvanK]

First up terminolgy Kommand Gerate is not fitted to the BF109 . It was a Mechanical engine control unit fiitted in the BMW801 that controlled a number of engine variables including Auto prop pitch on the FW190. The system on the 109 is a much more straight forward affair that concerns itself with Governed RPM only.

Auto prop pitch in the 109 installation was only "active" above a certain RPM (2000in the DB605 ...not 100% sure what is was on the DB601). A typical way to handle the Start Taxi Take off scenario is as follows. Start with prop pitch Full fine 12:00. Select Full throttle as RPM passes 2000 select AUTO. Personally I just take off in Manual get airborne and when the RPM gets to 2300 just select AUTO, since this is the Full throttle governed value. Coming in to land once I go back to manual and set 12:00 so max RPM in a hurry is available if required.

In general terms if you are using Max throttle then AUTO is the go imo. If you are using an intermediate setting like say a climb at 1.25ATA and dont want the commanded RPM (about 2000 in this case) then select manual and set 2300RPM for example. In combat with large TAS changes etc AUTO frees you up from sweating on the RPM.

In the end I think intelligent use of both AUTO and Manual is required to get the best out the engine.

In addition the way it seems to be mechanised in Sin is when you close the the Throttle and RPM goes below 1500 then prop fines up eventually to the 12:00 position. I guess it figures its ready for a max power application ... like in a Go Around situation etc.