109 cant do XXXX anymore.

[VO101_Tom]

Originally Posted by 41Sqn_Stormcrow

However, I also realized that pushing the lever up will make the pp go up but the pp does not stop increasing when releasing the lever. ...

Hi. I don't know what may be your trouble (axis maybe?), this works at me. I release the lever, the increase/decrease of the propeller-pitch stops. Sometimes a couple of degrees moves longer, but nonsignificant (at the start, it may not respond to the lever until almost a full 6° turn... but there is OK after take-off).

[IvanK]

Wrt to Oxy systems. Above 30,000feet (in an unpressurised cockpit) even 100% Oxy is not sufficient. Above 30,000feet an Oxy regulator needs to produce an overpressure at 100% Oxy to keep O2 partial pressures in the blood to acceptable/viable levels. I am not sure if WW2 regulators could automatically produce this required overpressure.

In a pressurised cockpit its not an issue until the Cabin Altitude goes over 30,000feet, then the same arises. B29s were of course pressurised.

Originally Posted by VO101_Tom

Hi. I don't know what may be your trouble (axis maybe?), this works at me. I release the lever, the increase/decrease of the propeller-pitch stops. Sometimes a couple of degrees moves longer, but nonsignificant (at the start, it may not respond to the lever until almost a full 6° turn... but there is OK after take-off).

Of course, if you only do this a very little bit, it will stop quicker. But still there is a considerable delay between releasing the lever and stopping of the clock arms turning. The longer you push the lever the longer the delay.
I do understand that some delay may occur in reality between pushing/releasing the lever and the clock and the proppitch. But this delay should at least be constant and independent of how long the lever is pushed. This really does not make any sense.

[robtek]

I believe it might be because the electric motor driving a high ratio gear mechanism has a inertia that keeps moving a short while even without energy.
As the indikator shows minuscule changes, making them look bigger.

Agreed that there is some delay as I wrote. But I doubt that this delay is proportional to the duration with which one pushes the lever, particularly for an electrical engine which has very fast rampage speeds. Or have you ever seen an electrical mixer taking longer to stop when using it longer? It will be almost constant as it won't accelerate until you release to button. It will accelerate a short time until reaching its operating speed. So I do think that the delay should be constant except for very very short durations of lever pushing.

And I also doubt that the delay can be very long as the ratio is not that excessive and the electric engine will work as a braking system as soon as it is ordered to stop.

[TomcatViP]

Its hydraulic. There is a backup electrical motor for use when the DB engine is off.

The battery at the time were not what we we are use to today. This is why it's slow before eng is on and faster after when the circuit is switched to hydrau.

The 109 was an impressive design for it's time.

This has been discussed alrdy extensively and what we hve now is very accurate (in fact a reference for any future sim)


~S

[VO101_Tom]

Originally Posted by TomcatViP

Its hydraulic. There is a backup electrical motor for use when the DB engine is off.

The battery at the time were not what we we are use to today. This is why it's slow before eng is on and faster after when the circuit is switched to hydrau.

The 109 was an impressive design for it's time.

This has been discussed alrdy extensively and what we hve now is very accurate (in fact a reference for any future sim)


~S

Hi. No, the 109's VDM propeller-pitch has no hidraulic part (reliable, hydraulics damage does not have an effect on it). Because of this slow (compared with the hydraulic PPs).

I thought 41Sqn_Stormcrow writes because of a control bug, but in this he is right, the electrical motors has no delay. It would be necessary to correct the 109 one in so many trifles that I did not notice this.

[VO101_Tom]

Originally Posted by cheesehawk

I thought the modelling on it was weird too, but after using the 109 for a few hours, its quite natural, and whether wrong or not, easy enough to use and set precise prop pitch becomes second nature. Still a million times better than the set-and-forget of 1946.

I'll probably miss the manual prop pitch when the automated systems come out for the later series 109s....

You may switch it off anytime

[TomcatViP]

Originally Posted by VO101_Tom

Hi. No, the 109's VDM propeller-pitch has no hidraulic part (reliable, hydraulics damage does not have an effect on it). Because of this slow (compared with the hydraulic PPs).

I thought 41Sqn_Stormcrow writes because of a control bug, but in this he is right, the electrical motors has no delay. It would be necessary to correct the 109 one in so many trifles that I did not notice this.

Huh... I was so sure of me

Thx Tom for the doc (by the way you ruined my Sunday as I hate hving to read electrical scheme )