PDA

View Full Version : P-38 Automatic Propellor pitch?



Xnomad
03-12-2004, 11:46 AM
Please pardon me if this has been mentioned before or if I'm completely wrong. Shouldn't the propellor pitch be on automatic for the P-38?

From what I have read and heard, the Lightning was known to have propellors that would 'run away' if a circuit failed or they were left outside in bad weather a lot. Also if you used manual propellor pitch you were likely to damage the engine just like in the Bf 109.

Shouldn't this be the case with the AEP Lightnings or are they a different series from the Lightnings I have heard about?

http://www.xnomad.pwp.blueyonder.co.uk/sig.jpg

Xnomad
03-12-2004, 11:46 AM
Please pardon me if this has been mentioned before or if I'm completely wrong. Shouldn't the propellor pitch be on automatic for the P-38?

From what I have read and heard, the Lightning was known to have propellors that would 'run away' if a circuit failed or they were left outside in bad weather a lot. Also if you used manual propellor pitch you were likely to damage the engine just like in the Bf 109.

Shouldn't this be the case with the AEP Lightnings or are they a different series from the Lightnings I have heard about?

http://www.xnomad.pwp.blueyonder.co.uk/sig.jpg

VW-IceFire
03-12-2004, 12:00 PM
I think all propellors can "run away" if in certain conditions. Unless something is different for the P-38 all Allied planes have constant speed propellors which essentially means that the RPM's are on a governor that is part of the throttle. While the Bf 109 can be auto or independent. This is one of those workload reducing things.

What prop pitch in FB does on such a plane is let you set the RPM's so you can lower rpm's for cruising speeds for instance.

http://home.cogeco.ca/~cczerneda/sigs/temp_sig1.jpg
RCAF 412 Falcon Squadron - "Swift to Avenge"

VMF513_Sandman
03-12-2004, 04:02 PM
in zeno's warbirds.com, they have a film on the p-38. and they did mention something about a 'propeller govener' as 1 of the things on the checklist before take-off. according to the p-38-L chart, it also mentions mixture settings: auto-lean/rich, propeller rpm, etc.

from what i can see from the charts and to fb, seems that the L is modeled (chartwise) to within 95% of specs. but what's missing is, ability to switch tanks, cut fuel to a damaged engine, being able to adjust mixture. i'd assume u wouldnt have a '1 setting for everything' on an actual 38 like fb. i thought the dive brake was on the tail...i see it under the wings. hmmmm

pinche_bolillo
03-12-2004, 04:28 PM
in the p-38's pilot's manual the term fixed pitch comes up and it differes from auto pitch. under fixed pitch the term increase propellor rpm and decrease propellor rpm are used. doesnt this mean that if the prop govenors give out the pilot can resort to manual pitch to gain some control back from a run away prop.

I cannot imagine any pilot no matter how good would be able to maintain proper propellor pitch with power increases and speed increases. the changes would have to be constant and every spit second under those conditions to keep the engine from over speeding or from being bogged down. I do believe however that he could use manual pitch under certain power settings and medium speeds to gain enough control to get his a/c back to base.

JG53Frankyboy
03-13-2004, 04:36 AM
"I cannot imagine any pilot no matter how good would be able to maintain proper propellor pitch with power increases and speed increases. the changes would have to be constant and every spit second under those conditions to keep the engine from over speeding or from being bogged down. "

well, that was the way how Lw pilots flew their Bf109E in combat 1940 over UK http://ubbxforums.ubi.com/infopop/emoticons/icon_wink.gif
they had the pitch control on the throttlelever , used by the thumb http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

ucanfly
03-13-2004, 12:21 PM
That is how most like to fly the 109s in this game , it seems. Just think of it as a manual transmission for your propeller - -with lots of gears!