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Hawgdog
10-03-2003, 08:18 PM
the faq says "A: The low number settings are like the low gears of a car, the higher numbers the high gears. If go with the numerical settings you have the equivalent a manual transmission airplane."


Huh? I thought it was like the prop pitch on a boat motor, less angle (i.e. lower numbers) for faster speed...well, to a point.
Higher pitch, more bite, good for take offs and lower speed torque- to the point of cavatation.

duh......now what. simple please, its the dawg you know.


<center></script>The original HawgDog, dont be fooled by fneb imitations
~W~ cause S! has become USELESS
When you get to hell, tell 'em Hawgdog sent you
http://users.zoominternet.net/~cgatewood/assets/images/sharkdog.gif

Hawgdog
10-03-2003, 08:18 PM
the faq says "A: The low number settings are like the low gears of a car, the higher numbers the high gears. If go with the numerical settings you have the equivalent a manual transmission airplane."


Huh? I thought it was like the prop pitch on a boat motor, less angle (i.e. lower numbers) for faster speed...well, to a point.
Higher pitch, more bite, good for take offs and lower speed torque- to the point of cavatation.

duh......now what. simple please, its the dawg you know.


<center></script>The original HawgDog, dont be fooled by fneb imitations
~W~ cause S! has become USELESS
When you get to hell, tell 'em Hawgdog sent you
http://users.zoominternet.net/~cgatewood/assets/images/sharkdog.gif

XyZspineZyX
10-03-2003, 08:22 PM
LOL! Out comes the Shakespere with 20lb test.
Whizzzzzzzzzzzzzzzzzzz!

Hawgdog
10-03-2003, 08:28 PM
LilHorse wrote:
- LOL! Out comes the Shakespere with 20lb test.
- Whizzzzzzzzzzzzzzzzzzz!

spare me, I'm serious.
I've been screwing around with the pitch, at higher speeds I've been backing it off to 85-90% at high speeds.
Believe me, Id rather use the lame search engine for facts than be accused of trolling.
I had assumed (trying to learn the He-111) that 100% to take off was the key.

input, no razzes thanks-




<center></script>The original HawgDog, dont be fooled by fneb imitations
~W~ cause S! has become USELESS
When you get to hell, tell 'em Hawgdog sent you
http://users.zoominternet.net/~cgatewood/assets/images/sharkdog.gif

XyZspineZyX
10-03-2003, 08:49 PM
100% RPM or fine pitch (the high pitch numbers) is what you use for takeoff. Absolutely correct.

The car gear analogy is seriously flawed and pretty much useless if you want to explain prop pitch at a level enabling someone to fly using it.

Cheers,
Fred

"If we are an arrogant nation, they will resent us. If we are a humble nation, but strong, they will welcome us."
- George W. Bush, during his campaign. No comment.

(Quote brought back by popular demand - RBJ missed it so much he mailed me about it)

XyZspineZyX
10-03-2003, 09:18 PM
Pitch in FB suks.............Dosent work like gear box ,
its biteing air. Like youre DOG .
Parts on LA7 tres hombres~ fall off over 700 anyway
Who cares.................................../i/smilies/16x16_smiley-very-happy.gif

The genuine Hawg-dawg....USA
Proud former member of Kelly Johnson's "SKUNK WORKS"
Fat Boys and.... Props Forever....Baby

XyZspineZyX
10-03-2003, 09:23 PM
for the he111 I use 100% for takeoff/climb and 80% for level flight with bombs, 75-80% level flight without bombs.

XyZspineZyX
10-03-2003, 09:27 PM
Hawgdog wrote:
-
- LilHorse wrote:
-- LOL! Out comes the Shakespere with 20lb test.
-- Whizzzzzzzzzzzzzzzzzzz!
-
- spare me, I'm serious.
- I've been screwing around with the pitch, at higher
- speeds I've been backing it off to 85-90% at high
- speeds.
- Believe me, Id rather use the lame search engine for
- facts than be accused of trolling.
- I had assumed (trying to learn the He-111) that 100%
- to take off was the key.
-
- input, no razzes thanks-


Sorry, Hawgdog. You being one of the oldies, I thought you were having a bit of fun.

But, Fred is right higher numbers are fine pitch, lower to coarsen. 100% or 95% for take-off. Coarsen some more for speed and climb out. Coarsen some more to lower RPMs for cruise.

Good luck with the 111. You're a better man than I there.

Hawgdog
10-03-2003, 09:35 PM
Thanks for input- I'm in HP now flying the He-111, I'll be dammed, I can get some good speed reducing the pitch to 75 over the water with bombs, and no over heat (open to 6- throttle at 80%) Same speed prior with 100% throttle and pitch to 100 with rad open to 4!!

kudos

doggie out and back to flying, ah, welcome the weekend- friday night at the fights!!!!



<center></script>The original HawgDog, dont be fooled by fneb imitations
~W~ cause S! has become USELESS
When you get to hell, tell 'em Hawgdog sent you
http://users.zoominternet.net/~cgatewood/assets/images/sharkdog.gif

XyZspineZyX
10-03-2003, 11:41 PM
LilHorse wrote:

-
- But, Fred is right higher numbers are fine pitch,
- lower to coarsen. 100% or 95% for take-off.
- Coarsen some more for speed and climb out. Coarsen
- some more to lower RPMs for cruise.
-
- Good luck with the 111. You're a better man than I
- there.
-
-

Depends on whether you're talking constant speed prop or variable pitch. With a CS prop, although the blade angle does coarsen at higher speed, you don't need to change anything. For max power set 100% and that's it. At high speed, or at low speed in a climb you want 100% for max power. You might set lower settings to reduce wear and tear, or heating. It seems around 90% corresponds to the max continuous power setting for most types, so would be the normal recommended climb setting. Anything from 50-75% seems to give typical cruise rpm.

Unfortunately, it seems you need to manually play with the variable pitch props to get best performance - even the supposedly auto ones. As speed increases you need to coarsen the blade angle to keep rpm within limits.

FWIW, what I use in the 111 (I keep power=pitch, so fig applies to both):

T/O 100%
Climb 90%
Cruise 60% (gives around 280 ias)
Landing is the exception, as prop is set to 100% ready for an overshoot, while power is reduced to 0%.

Kernow
249 IAP