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zxwings
03-06-2008, 09:31 PM
The airwarfare page on complex engine managment
http://www.airwarfare.com/Sims/FB/fb_cem.htm mentions this file: fbengines.pdf. Although the original link to it doesn't work any longer, I have found the file here:
http://www.eaf51.org/newweb/Download/Utility/fbengines.pdf

In this document, there are comments about the FW190A's propeller pitch control, which read:

"Aeromech [auto] is default. If you switch to emergency variable pitch, it locks the propeller at an intermediate setting and you CAN'T switch back per flight."

and

"Don't turn off [auto prop pitch] for the FW-190A/F series. You're stuck in manual at emergency intermediate settings for the rest of flight!"

The words in bold type sound confusing! So what do they actually mean? Do they mean that after switching to "manual", you can't switch back to "auto" again and, aslo, your manual control doesn't work properly any more?

What's more, have you 190a pilots ever experienced anything strange about the 190's engine related to prop pitch control? Personally, I sometimes see my 190a's engine malfunction without having made apparent mistakes in the handling of the prop pitch.

Ratsack
03-06-2008, 10:21 PM
It's just wrong.

The propeller controls for the Fw 190 A in the game work as follows:

1. It always starts in auto.

2. If you switch to manual, it will go to 100% by default. This means that it is giving maximum RPM for that throttle setting / speed / altitude.

3. If you switch back to auto, it goes to auto (I have no idea what the other guys were talking about).

4. If you are in manual and you reduce the 'pitch' to 80% (for example), it will reduce your revs a bit. If you try to go back to auto it will do so without a problem. If you go from auto back to manual, it will go directly to wherever you last left it in manual (in this case, 80%).

This means you can pre-set the pitch to, say, 80%, then cruise in auto. When you want to go to combat all you need do is switch to manual and it go to 80% straight away.



I suspose it's possible that what the other site was talking about was the real Fw 190 A. In the real plane the pilot didn't turn off the automatic control (the Kommandogerrat) unless there was something badly wrong. Manual control was for limp-home mode.

cheers,
Ratsack

Rammjaeger
03-07-2008, 12:02 AM
If you turn auto pitch off in a Fw-190 or a Bf-109, be sure to immediately set it to no more than 30%. Otherwise the engine will get cooked. Manual prop pitch in these types should be no more than 30% in level flight and 10-20% in dive.

M_Gunz
03-07-2008, 01:02 AM
Manual pitch is totally different between 109 and 190. In 109 you are setting % of full
range prop blade angle, from fine stop at zero to coarse stop at 100%.
With every other prop that has manual what I see is percent of rpm desired, engine adjusts
prop to suit even the FW's.
How fast you are going in 109 affects what prop pitch you need. Also don't overpower the
prop, change pitch and then power when increasing to avoid over-revving the 109.

To fly 109 on manual I got my power set and changed my pitch with speed for the best bite.
After a while it's like driving a stick, you know by the sound of the engine when it is
time to change gear but in a plane you can just hold the engine sound right by changing
your prop pitch. 2500-2600 rpm sounds good to me in 109's.

Redwulf__26
03-07-2008, 02:42 AM
As I understand it 100% is Fine pitch, and 0 % is Coarse. Pitch relates to the distance travelled per revolution of the prop. Going from 100 to 0 increases the pitch. In the Fw (I don't know why the Me is so different) you will find that if you switch from auto to manual for the first time, 100% will be selected. If you then select a pitch setting in manual, it will be remembered next time you go from auto to manual. I suspect that the "intermediate setting" is just for emergencies if the auto pitch control fails for any reason. You don't want the prop pitch to go fine on a high power setting, but it still has to be useable at low power and speed settings, like when landing.

Having asked an ex Fw and Me pilot, they said they never used manual pitch as they were far to busy with other stuff while flying. Even in "full switch" I think IL2 makes things easy comparired to RL.

JG53Frankyboy
03-07-2008, 04:32 AM
well, actually "pitch" is the wrong word what is controled by the lever in a plane equitped with a ConstantSpeedPropeller - you control the engine rpm !
the propeller controls itself the propellerbladeangle to mantain the "ordered" rpm.

totaly different to a system where the lever controls the angle directly - like in the 109 in manual mode.


i wrote in the past the following summary:
for all piston engined planes except:
Ki-27
J8A
TB-3s
Fw190 in auto mode
Ta152H in auto mode
Spitfire IX and VIII in auto mode
Bf109, Bf110,Do335,Ta152C in manual and auto mode:
the prop pitch in game is controlling the engine revolutions - so 100% pitch here means you allow the egnine to run at max rpm if enough throttle/power is available.
in combat you shoud fly always with 100%.
to lower your pitch is actually only necesarry if you want realy fly slow (that your comrades or the AI can close formation or you want safe fuel) , than you have to reduce the pitch like the throttle. same % rate or pitch 10% more than the throttle % is a good solution.

also using full throttle and useing only 90-95% pitch can reduce the overheat chance - usefull in some planes like the Tempest or the Corsair and Hellcat. that doesnt harm your speed/climb much, if at all !

very few planes in game are overrev in a power dive (full power, 100% pitch) - IIRC that are the Cr.42, G.50, Mc.200, Fw190A/F in manual mode, Fw190D/Ta152H in manual mode, the Brewsters(not sure about that , may have changed in a patch)


Fw190 in auto mode
Spitfire IX and VIII in auto mode
Bf109, Bf110,Do335,Ta152C in auto mode:
have a one lever system, if you control the throttle, the pitch is automaticly also controled


Bf109, Bf110,Do335,Ta152C in manual mode:
thats totaly different, here you control the propeller blade angle direclty ! no automatic will keep the rpm in a "good" condition. it brings you no benefit to use this manual settings anymore (there was a time ). so, dont bother it

the
Ki-27
J8A
TB-3s:
have fixed propellers, so nothing to control there

M_Gunz
03-07-2008, 12:58 PM
Originally posted by Redwulf__26:
As I understand it 100% is Fine pitch, and 0 % is Coarse. Pitch relates to the distance travelled per revolution of the prop. Going from 100 to 0 increases the pitch. In the Fw (I don't know why the Me is so different) you will find that if you switch from auto to manual for the first time, 100% will be selected. If you then select a pitch setting in manual, it will be remembered next time you go from auto to manual. I suspect that the "intermediate setting" is just for emergencies if the auto pitch control fails for any reason. You don't want the prop pitch to go fine on a high power setting, but it still has to be useable at low power and speed settings, like when landing.

Having asked an ex Fw and Me pilot, they said they never used manual pitch as they were far to busy with other stuff while flying. Even in "full switch" I think IL2 makes things easy comparired to RL.

There was a sim-exploit that used the instant-100% that went with the switch to auto, this is
the fix?

thefruitbat
03-07-2008, 01:02 PM
Hi Frankyboy, with regards to the fw190, whilst as you point out, you dont gain any performance benefits from flying with manual prop pitch in terms of speed, can you benefit from the point of view of a) fuel ecomomy, and b) keeping the enginge cooler, or are you better off just reducing the throttle for both of these?

fruitbat

JG53Frankyboy
03-07-2008, 01:06 PM
Originally posted by thefruitbat:
Hi Frankyboy, with regards to the fw190, whilst as you point out, you dont gain any performance benefits from flying with manual prop pitch in terms of speed, can you benefit from the point of view of a) fuel ecomomy, and b) keeping the enginge cooler, or are you better off just reducing the throttle for both of these?

fruitbat

actually i said that about the 109 in manual.
the Fw190 IS little bit faster in manual than in auto !
and espacially climbs and accelerated much better - so my recommondation about flying the Fw190 is : in combat always in manual http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

BSS_Sniper
03-07-2008, 01:09 PM
Originally posted by JG53Frankyboy:
well, actually "pitch" is the wrong word what is controled by the lever in a plane equitped with a ConstantSpeedPropeller - you control the engine rpm !
the propeller controls itself the propellerbladeangle to mantain the "ordered" rpm.

The pitch of the blade is changed along with the rpm. Thats why you can't run higher MP with lower RPM's or you're screw the engine. Another thing missing here where people are running 30% pp with full throttle. I fly CSP on a daily basis for work.

thefruitbat
03-07-2008, 01:25 PM
Originally posted by JG53Frankyboy:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by thefruitbat:
Hi Frankyboy, with regards to the fw190, whilst as you point out, you dont gain any performance benefits from flying with manual prop pitch in terms of speed, can you benefit from the point of view of a) fuel ecomomy, and b) keeping the enginge cooler, or are you better off just reducing the throttle for both of these?

fruitbat

actually i said that about the 109 in manual.
the Fw190 IS little bit faster in manual than in auto !
and espacially climbs and accelerated much better - so my recommondation about flying the Fw190 is : in combat always in manual http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>

Doh! my bad!!

Ok, same question for the 109!!

Also, what revs is optimum for the 190?

fruitbat

zxwings
03-08-2008, 03:09 AM
Originally posted by Ratsack:
It's just wrong.
...
If you try to go back to auto it will do so without a problem. (in this case, 80%).

I believe you are right. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

zxwings
03-08-2008, 03:18 AM
Originally posted by Rammjaeger:
If you turn auto pitch off in a Fw-190 or a Bf-109, be sure to immediately set it to no more than 30%. Otherwise the engine will get cooked. Manual prop pitch in these types should be no more than 30% in level flight and 10-20% in dive.
Isn't 30% too small? As I know, some people set it to 85% in level flight - when escaping, for instance - and it is ok.

Ratsack
03-08-2008, 03:26 AM
It will be too low in the Focke-Wulf. The Me109, however, has a different prop.

cheers,
Ratsack

M_Gunz
03-08-2008, 07:32 AM
How fast you're moving affects the 109 manual pitch angle, it must coarsen with speed to load
the engine. Ever blown the engine on a 109 right after takeoff while using manual pitch?
You get fast enough on full fine and the prop is hardly pulling, all that engine power has
to do something. What gave enough drag sitting on the ground and taxiing didn't at about
230 I guess, until I remembered to start coarsening the prop when revs went up.
I prefer manual to automatic in cars too.

One thing anyone can try is diving beyond level top speed and see if reducing CSP pitch don't help.

Remember that IAS will be less than TAS when you're saying "top speed now", discussion and chart here. (http://homepage.eircom.net/%7Efrontacs/WBStored/IASvsTAS.html)


Jeffrey Dillman

Alt. factor Alt. factor

1k 1.017 21k 1.394

2k 1.031 22k 1.417

3k 1.047 23k 1.443

4k 1.063 24k 1.470

5k 1.078 (1.077) 25k 1.497


6k 1.097 26k 1.523

7k 1.113 27k 1.551

8k 1.130 28k 1.576

9k 1.149 29k 1.609

10k 1.167 (1.164) 30k 1.634 (1.635)

11k 1.186 31k 1.669

12k 1.203 32k 1.697

13k 1.223 33k 1.733

14k 1.244 34k 1.763

15k 1.263 35k 1.798

16k 1.286 36k 1.833

17k 1.303 37k 1.880

18k 1.329 38k 1.923

19k 1.349 39k 1.970

20k 1.373 (1.370) 40k 2.018 (2.016)

Jeffrey Dillman


So 437mph TAS at 25k ft (P-51D?) reads more like 291mph on the guage, at 25k ft.
And 318mph at 20k ft -- wth, you're in a dive right?

Anyway I see it as up to the top level speed your engine has the power to turn the prop at
full rpm. You go faster then you need to reduce the required rpm, the pitch -- see if it
isn't that way in IL2. What happens if at good speed say 360kph you reduce power to 50%
and leave rpm at 100%? You slow down in pretty good order, high rpm at low power is how
to control speed on approach at least in IL2. If you reduce power and rpm from good speed
then you won't slow down nearly as fast. Reduced pitch in high speed dives works too.