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Huge problem with throttle function on all aircraft with time limited settings.

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the thing is, that topic is really interesting and relevant. But OP manages to make it a personal vendetta and even undermines any practical purpose we could get out of this.
He isnt triing to proof anything. Or to convince somebody. He just likes to see "the world" burn. Because reasons. So lets try and fight that with some super dry facts.

Edited by DerSheriff
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13 minutes ago, DerSheriff said:

the thing is, that topic is really interesting and relevant. But OP manages to make it a personal vendetta and even undermines any practical purpose we could get out of this.
He isnt triing to proof anything. Or to convince somebody. He just likes to see "the world" burn. Because reasons. So lets try and fight that with some super dry facts.

 

Actually I cannot be bothered, even if one was comfortably sitting in a nice pub discussing with the OP I don't believe it would be a pleasant conversation

 

had my little say and i'm out :cool: others are free to continue of course

 

Cheers, Dakpilot

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33 minutes ago, DerSheriff said:


Oh of course you get the RPMs. You haven't understood the propeller. as the air gets thinner the propeller gets more fine and tries to grab more air while holding the same RPM.
The table you just posted is just the coresponding RPM to that manifold pressure. That "verstellpropeller" is a constant speed propeller if that is still up for debate. Its exactly that.

 

I think I understand the propeller Sheriff. But  a Bf109 automatischer Verstellpropeller does not work in the same way as a constant speed propeller. You set boost and rpm with a certain position of the throttle. IMO the question is now if rpm is set only by the throttle position or does the governor try to hold a set rpm due to a certain boost level? If the mechanism takes its setting from a exact position of the lever the engine would rev higher above critical height (like Notleistung). If it takes the setting from boost the revs would stay within the intended range even above critical height and full lever.

 

Maybe someone can provide a manual how the lever has exactly worked? Could not find a document yet.

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32 minutes ago, StG2_Manfred said:

if rpm is set only by the throttle position or does the governor try to hold a set rpm due to a certain boost level? If the mechanism takes its setting from a exact position of the lever the engine would rev higher above critical height (like Notleistung)

that it is.
Edit:
Anything else makes no sense. Since you need that RPM higher up to still be able to climb and to accelerate. If at 1.15ata only ~2000RPM would be available that would be really bad.

Edited by DerSheriff

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5 hours ago, DerSheriff said:

that it is.
Edit:
Anything else makes no sense. Since you need that RPM higher up to still be able to climb and to accelerate. If at 1.15ata only ~2000RPM would be available that would be really bad.

 

The question did not leave me 

 

Now I found the answer. Your assumption is correct, the mechanism is connected directly with the throttle linkage. I've attached the important parts .... 

 

 

EDIT: What still remains: full boost rpm is considered as uncritical for DB 601A/B after you passed critical height, as it is explicitly stated.

Now it would be interesting to know more about other motor variants regarding rpms.

 

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Edited by StG2_Manfred
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Fumes, in game the engine limits are for a specified manifold pressure and RPM, if you change one (or both) of these settings the time limit will go up or down (as the engine will be more or less stressed). How much this does depends in how far away are the specified timers in the RPM and manifold pressure range.

For example for planes like the Spit, P-40, P-39, Ju 87, Ju 88 and He 111 you can change both RPM and manifold pressure and experiment with different combinations. This doesn't normally happen with the German fighters because they have determined RPM/manifold pressure, but when they hit critical altitude the manifold pressure starts to drop while the RPM still go on. You will have more time at full throttle than at sea level at high altitudes because the engine runs at a lower manifold pressure, however by keeping full RPM it will still be a rather shorteish time because that tends to be the more important parameter (like allied planes have in their 3000 RPM emergency regimes).

You can try for example using manual pitch in the F-4 to test say 1.3 ata at 2500 RPM vs 1.3 ata at 2700 RPM, and then 1.42 ata at 2500 RPM vs 1.42 ata at 2700 RPM and see which parameter has more weight, I guess the RPM would be the most important.  While there aren't official limits for these intermediate settings the devs create a continuous function so intermediate settings give intermediate time limits (otherwise how would they code when the 30 mins ends and the 1 min begins? it's a too abrupt change). Also once you have more than 2-3 min limit there is a good amount of randomization and you will need to do several tests for each setting because there is some variation to it (some planes more than others, and the F-4 particularly does have plenty of variation on intermediate settings).

 

 

This is how the in game system works basically, I personally think it's too strict but the way it works in the intermediate engine MP/RPM combinations seems logical to me.

Edited by -=PHX=-SuperEtendard

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Ingame test results
Bf 109 F-4, full throttle 2700 RPM at 6000 meters (1.26 ata):
2:46
2:35
5:18
2:31
3:30
2:32
3:45
2:17
3:34
3:14
So final result: 3:12 +/- 51 seconds

@SuperEtendard provided some testnumbers. I tested full power on the deck in the F-4 a while back and came to 1,5mins as an average seize time.

Edited by DerSheriff

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Thanks for the test Sheriff! 

 

I would expect those numbers when full manifold pressure is available.

 

And for DB601A/B there should be no limit, like it is in the manual. 2400 rpm were not critical as it seems. 

Edited by StG2_Manfred

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