You know it's a good kill when...

[IvanK]

Originally Posted by cheesehawk

Ok, still getting my head around it, so if you disable the autoPP, pull the throttle back, fiddle with the PP to get the ratio you want, then re-enable the PP, it will give you a sort of relationship from the throttle to the actual PP based upon the combination at the time the PP is set? So setting a lower throttle position (say 50%) and fining the PP to still give you 2200rpm, would give you an AutoPP that tries to keep a fine PP as you increase the throttle, until you reach a safety point when it would automatically coarsen the pitch?

No. As Doogles said once you select AUTO it will always give you the ATA/RPM relationship AUTO has been calibrated to. (Being nit pickky remember RPM demanded is a function of throttle position). If you dont like the combination AUTO gives you then select MANUAL and Set whatever combination you desire.

[IvanK]

I am not sure if this VDM chart helps the discussion. I hope might give the desired ideal AUTO RPM relationship ?

Not being a German speaker means I am in the hands of On line translators.



The various Engine and prop combinations are there.

[Insuber]

Great info there Ivank! Thank you mate!

[TomcatViP]

IvanK are you time travelling ?

[Robo.]

Originally Posted by TomcatViP

IvanK are you time travelling ?

Not quite sure what you mean, but the 601A + 9-9518B is legit in 1940.

[TomcatViP]

sry I was jocking making fun of the ability of Ivan to dig out interesting material.

What I see on this chart :

Prop pitch value in function of engine rpm corrected by the speed regulator that hve a f=1-kx² law.

My guess : x² stand for the dyn pressure and k stand for the ro correction

That way basically we have the linear rules btw eng rpm and blade pitch that lead to the throttle only ctrled characteristic of the automation system. Clever ...

WHat it means for us (speculation again )?

you might hve to reset the syst one way or another in certain conditions. Wasn't there a reset button or a mention to a certain procedure in the manual like throttling full back ?

[Robo.]

Oh yeah TomcatViP, got it now, and thanks for the info, makes sense!

Regarding the auto mode as we talk about it - it would be worth testing if the revs increase above 5500m automatically:

''The devices for the automatic regulations of the revs
hitherto used will be modified by Messerschmitt and VDM as quickly as
possible so that the short period increase in revs to 2600 for the
DB 601 A and 2800 for the DB 601 N permissable above the full pressure
height can also be made by the automatic device.''

The maximum permitted RPM for DB 601A-1 was 2400, which could be exceeded for short period of time above 5500m - up to 2600RPM.

[Flanker35M]

S!

No worries Continu0 This is just a game and I lost my SA for a while. Hope to see you in the air!

Great stuff IvanK Documentation like this = less whining

[IvanK]

Originally Posted by Robo.

Oh yeah TomcatViP, got it now, and thanks for the info, makes sense!

Regarding the auto mode as we talk about it - it would be worth testing if the revs increase above 5500m automatically:

''The devices for the automatic regulations of the revs
hitherto used will be modified by Messerschmitt and VDM as quickly as
possible so that the short period increase in revs to 2600 for the
DB 601 A and 2800 for the DB 601 N permissable above the full pressure
height can also be made by the automatic device.''

The maximum permitted RPM for DB 601A-1 was 2400, which could be exceeded for short period of time above 5500m - up to 2600RPM.

Here is the original source document to that statement Robo. This is an allied translation of a an original German source document. The exact provenance of this document is unknown, though it came to me by way of Schwarzeman. The document provides some interesting other details. The hand written date is I guess the only real point of debate.




On the subject of the ideal AUTO RPM versus ATA (Below FTH) Relationship I think we can deduce from various RAE test documents, A set BF109T pilots notes (DB601n though) that the most likely relationship would be.

1.4ATA/2600 (DB601N) .... 2400 DB601Aa
1.3ATA/2400
1.23ATA/2300
1.15ATA/2200
2000RPM min governed valued (now confirmed for DB601 from RLM docs).
Remembering of course that the actual determinant of RPM is throttle position

One further point is that in game a Static runup at 1.3ATA will only get you 2000RPM. You should be able to get 2300RPM at zero forward speed.

With these values in mind the Sim needs a little tweaking. Easily done from an instrumentation/animation point of view but the power output would need to reflect these values as well.

[Robo.]

Originally Posted by IvanK

On the subject of the ideal AUTO RPM versus ATA (Below FTH) Relationship I think we can deduce from various RAE test documents, A set BF109T pilots notes (DB601n though) that the most likely relationship would be.

1.4ATA/2600 (DB601N) .... 2400 DB601Aa
1.3ATA/2400
1.23ATA/2300
1.15ATA/2200
2000RPM min governed valued (now confirmed for DB601 from RLM docs).
Remembering of course that the actual determinant of RPM is throttle position

One further point is that in game a Static runup at 1.3ATA will only get you 2000RPM. You should be able to get 2300RPM at zero forward speed.

With these values in mind the Sim needs a little tweaking. Easily done from an instrumentation/animation point of view but the power output would need to reflect these values as well.

Great stuff IvanK, you're a star mate!