Prop angle of attack vs age

"Maxwell" luv2^fly99@cox.^net wrote in news:ZhKdk.20173$%q.11589
@newsfe24.lga:


wrote in message
...

I can understand why a poor -- as in not smooth -- paint job would
alter the prop's efficiency, but never would have guessed having a
fractional mm of paint ablated from the leading edge of the prop would
affect it that much. Tongue in cheek question -- did the natural color
of the prop clash with that color and scare the air, or something?

On a serious note, have you any thoughts as to why such a minor change
in shape would have such a remarkable change in efficiency? A 5 knot
change in airspeed is like reducing the manifold an inch or so, isn't
it? That's huge! It also suggests there may be very minor changes in
prop that could improve performance too.

---------------------------------------------------

You are absolutely right, and his is just exaggerating again as usual.

Like you'd know, fjukktard.

Just keep an eye on his posts, you will come to expect it in time.



Snort!


Bertie

On Jul 11, 12:14*pm, Bertie the Bunyip wrote:
"Maxwell" luv2^fly99@cox.^net wrote in news:ZhKdk.20173$%q.11589
@newsfe24.lga:







wrote in message
....

I can understand why a poor -- as in not smooth -- paint job would
alter the prop's efficiency, but never would have guessed having a
fractional mm of paint ablated from the leading edge of the prop would
affect it that much. Tongue in cheek question -- did the natural color
of the prop clash with that color and scare the air, or something?

On a serious note, have you any thoughts as to why such a minor change
in shape would have such a remarkable change in efficiency? A 5 knot
change in airspeed is like reducing the manifold an inch or so, isn't
it? That's huge! It also suggests there may be very minor changes in
prop that could improve performance too.

---------------------------------------------------

You are absolutely right, and his is just exaggerating again as usual.

Like you'd know, fjukktard.



Just keep an eye on his posts, you will come to expect it in time.

Snort!

Bertie- Hide quoted text -

- Show quoted text -

Not knowing much about props, what do you mean by "... they are each
2 inches of pitch apart." ?
I thought props were measured in dia. and angle ?

Thanks

"sid" wrote in message
...

Not knowing much about props, what do you mean by "... they are each
2 inches of pitch apart." ?
I thought props were measured in dia. and angle ?

Thanks

--------------------------------------------------------------------

A propellers angle or pitch is expressed in inches. Theoretically, a 24"
pitch prop has an angle that would travel 24" forward with each revolution,
at zero angle of attack. The smaller the number, the flatter the prop.

If that seems confusing, consider a right trangle. If the circumference of
the propeller arc at any given station is the base, the pitch is the height,
and the resulting angle is the pitch angle for that station. That's why
props have less angle at the tip, than at the root. Theoretically, it keeps
the entire lenght of the blade working at the same angle of attack.

Thus climb props are flatter or less pitch, and cruise props have more.

On Jul 11, 3:13*pm, "Maxwell" luv2^fly99@cox.^net wrote:
"sid" wrote in message

...

Not knowing much about props, what do you mean by *"... they are each
2 inches of pitch apart." ?
I thought props were measured in dia. and angle ?

Thanks

--------------------------------------------------------------------

A propellers angle or pitch is expressed in inches. Theoretically, a 24"
pitch prop has an angle that would travel 24" forward with each revolution,
at zero angle of attack. The smaller the number, the flatter the prop.

If that seems confusing, consider a right trangle. If the circumference of
the propeller arc at any given station is the base, the pitch is the height,
and the resulting angle is the pitch angle for that station. That's why
props have less angle at the tip, than at the root. Theoretically, it keeps
the entire lenght of the blade working at the same angle of attack.

Thus climb props are flatter or less pitch, and cruise props have more.

That’s a good explanation.

Looking in my Warrior II Information manual, the prop is listed as a:
Sensenich 74DM6-0-60 or 74DM6-0-58.
Is the "inches of pitch" encoded in that number ?

In article ,
sid wrote:

Looking in my Warrior II Information manual, the prop is listed as a:
Sensenich 74DM6-0-60 or 74DM6-0-58.
Is the "inches of pitch" encoded in that number ?

Yes. 60 and 58

--
Bob Noel
(goodness, please trim replies!!!)

On 2008-07-12, sid wrote:
Looking in my Warrior II Information manual, the prop is listed as a:
Sensenich 74DM6-0-60 or 74DM6-0-58.
Is the "inches of pitch" encoded in that number ?

Yup...the -60 or -58 is the pitch at 3/4 of the blade length. (The 74 is the
diameter in inches.)
--
Jay Maynard, K5ZC http://www.conmicro.com
http://jmaynard.livejournal.com http://www.tronguy.net
Fairmont, MN (FRM) (Yes, that's me!)
AMD Zodiac CH601XLi N55ZC (got it!)

"Maxwell" luv2^fly99@cox.^net wrote in
:


"sid" wrote in message
news:799b2347-57da-401d-b49a-d012f9053f35
@l42g2000hsc.googlegroups.com.
..

Not knowing much about props, what do you mean by "... they are each
2 inches of pitch apart." ?
I thought props were measured in dia. and angle ?

Thanks

--------------------------------------------------------------------

A propellers angle or pitch is expressed in inches. Theoretically, a
24" pitch prop has an angle that would travel 24" forward with each
revolution, at zero angle of attack. The smaller the number, the
flatter the prop.

If that seems confusing, consider a right trangle. If the
circumference of the propeller arc at any given station is the base,
the pitch is the height, and the resulting angle is the pitch angle
for that station. That's why props have less angle at the tip, than at
the root. Theoretically, it keeps the entire lenght of the blade
working at the same angle of attack.

Thus climb props are flatter or less pitch, and cruise props have
more.



nice cuat and paste luser boi.


Bertie