Whats the deal with counter-rotating props?

Think about what you do with your right foot during takeoff.

"Dico" wrote in message
oups.com...
Hello,

We're looking into a twin and the Twin Comanche is on our list. I know
that the later models have the counter rotating props -- although i
don't know too much about what this means, other than its "better".
Thanks,

Dico

On Sun, 29 Jan 2006 04:17:23 GMT, "Michael Ware" wrote:


"Dico" wrote in message
oups.com...

We're looking into a twin and the Twin Comanche is on our list. I know
that the later models have the counter rotating props -- although i
don't know too much about what this means, other than its "better".
Thanks,

Think about what you do with your right foot during takeoff.

Most trigear pilots are scratching themselves behind the right ear. :-)

Ron Wanttaja

On Sat, 28 Jan 2006 20:22:23 -0800, Ron Wanttaja
wrote:

On Sun, 29 Jan 2006 04:17:23 GMT, "Michael Ware" wrote:


"Dico" wrote in message
oups.com...

We're looking into a twin and the Twin Comanche is on our list. I know
that the later models have the counter rotating props -- although i
don't know too much about what this means, other than its "better".
Thanks,

Think about what you do with your right foot during takeoff.

Most trigear pilots are scratching themselves behind the right ear. :-)

Not the ones behind big engines. :-))

Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

Ron Wanttaja

I push the rudder with my right foot. This doesn't really answer my
questions though. Like I said, I'm not a "buff" and don't know much
about twins.

-Dico

that's right. i am trying to get you to think why you have to do this,
therefore leading to the reasons why you might want counter-rotating props.

"Dico" wrote in message
oups.com...
I push the rudder with my right foot. This doesn't really answer my
questions though. Like I said, I'm not a "buff" and don't know much
about twins.

-Dico

So with counter rotating props I won't have the plane want to go left?
Or I'd really have to hammer down the right rudder? Even worse if one
engine quit, I could be screwed? And I'm guessing the critical engine
comes into play here. Although I'm not sure if the critical engine
means its the good one (its critical you keep it) or the bad one (its
critical if you lose it)....

-Dico

"Dico" wrote in message
oups.com...
So with counter rotating props I won't have the plane want to go left?
Or I'd really have to hammer down the right rudder? Even worse if one
engine quit, I could be screwed? And I'm guessing the critical engine
comes into play here. Although I'm not sure if the critical engine
means its the good one (its critical you keep it) or the bad one (its
critical if you lose it)....

-Dico


Try Googling "minimum controllable airspeed"

Gerry

"Dico" wrote in message
oups.com...
So with counter rotating props I won't have the plane want to go left?

Correct. Not when they are both running, anyway!

Or I'd really have to hammer down the right rudder? Even worse if one
engine quit, I could be screwed? And I'm guessing the critical engine
comes into play here. Although I'm not sure if the critical engine
means its the good one (its critical you keep it) or the bad one (its
critical if you lose it)....

check this out.

http://avstop.com/Technical/twins.htm

Remember, too, that with a twin (except for planes like a Cessna 337) the
engines are not on the centerline of the fuselage, they are offset a few
feet.


-Dico

interesting... but a diagram with thrust vectors and with and without
counterrotating propellors would add to the clarification for this poster
BT

"Michael Ware" wrote in message
. ..

"Dico" wrote in message
oups.com...
So with counter rotating props I won't have the plane want to go left?

Correct. Not when they are both running, anyway!

Or I'd really have to hammer down the right rudder? Even worse if one
engine quit, I could be screwed? And I'm guessing the critical engine
comes into play here. Although I'm not sure if the critical engine
means its the good one (its critical you keep it) or the bad one (its
critical if you lose it)....

check this out.

http://avstop.com/Technical/twins.htm

Remember, too, that with a twin (except for planes like a Cessna 337) the
engines are not on the centerline of the fuselage, they are offset a few
feet.


-Dico

Thanks for the link.

A very interesting read! I'm that much smarter now!

Another question... can you retro fit planes so that they have CR
props? What kind of cost/job is involved? I am guessing that you'd
need an engine that turns the other way and a different prop... but i'm
sure there is a lot more to it.

-dr