Constant speed props
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Joined: Jan 2001
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From: UK
Constant speed props
I have done the search bit and found some good answers but can anyone point me in the direction of a guide to the operation of these? I need something to pass on for study (I am not very good at the techie explanations) from start up to touch down with practical hints.
Thanks
Thanks
Joined: Jul 2006
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From: The sunny south coast
http://www.thaitechnics.com/propeller/prop_control.html
just found this i have had a brief look seems to cover most of what I did in my atpls if you have any specific questions pm me and I will help if i can .
cheers.
just found this i have had a brief look seems to cover most of what I did in my atpls if you have any specific questions pm me and I will help if i can .
cheers.
Joined: May 2005
Posts: 421
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From: UK
Thorough background and theory from John Deakin on AvWeb.
Deakin: Props, Manifold Pressure & Mixture.
Yet more from Deakin.
(Free registration required for the links above).
A readable article from the PFA giving the essentials. (PDF)
Deakin: Props, Manifold Pressure & Mixture.
Yet more from Deakin.
(Free registration required for the links above).
A readable article from the PFA giving the essentials. (PDF)
Joined: Oct 2004
Posts: 762
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From: UK
very important
One of the most important things to remember is that if you tap a pen down the length of the prop it will make a different noise from root to tip. That is because it is a variable pitch prop.
And vice versa for a fixed pitch prop. Except that it makes the same noise.
Its all a bit technical but i know.
And vice versa for a fixed pitch prop. Except that it makes the same noise.
Its all a bit technical but i know.
Joined: Oct 2004
Posts: 762
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From: UK
thanks dublinpilot
Yes, dublinpilot is right. I am taking the p a bit. Only cos i was bored.
But, Its great that some of you fell for it. In a totally non offensive nice way of course.
It was a joke that the CAA examiner on my IR did to me. Except he kept me guessing for about 5 minutes why the pen made a different noise.
And if any of you say you are not going to try that out with people on a lovely summers day at your airfield, then you are a cad.
But, Its great that some of you fell for it. In a totally non offensive nice way of course.

It was a joke that the CAA examiner on my IR did to me. Except he kept me guessing for about 5 minutes why the pen made a different noise.
And if any of you say you are not going to try that out with people on a lovely summers day at your airfield, then you are a cad.
Joined: Feb 2005
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From: On Earth
Upto The Buffers

Joined: Apr 2006
Aviation Qualifications: CPL
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From: Leeds/Bradford
I've always thought of it as (bad analogy coming up) the equivilent of a gearbox in a car, but when I've used it to explain to other people they seem to have got the idea.
A car has a gearbox, you pull away in 1st gear. In a plane you take off with prop set to full fine. In a car when you get to your desired speed you take your foot off the gas and knock it into a higher gear. In a plane you pull the throttle back and course the prop out. And don't forget you want it full fine again when you're coming into land - helps you get the speed off, and well, you know what happens when you try to pull away in a car with 4th gear selected... don't want that kind of thing when you're going around!
A car has a gearbox, you pull away in 1st gear. In a plane you take off with prop set to full fine. In a car when you get to your desired speed you take your foot off the gas and knock it into a higher gear. In a plane you pull the throttle back and course the prop out. And don't forget you want it full fine again when you're coming into land - helps you get the speed off, and well, you know what happens when you try to pull away in a car with 4th gear selected... don't want that kind of thing when you're going around!
Joined: Oct 2004
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From: UK
Cusco
You seem to be following my details. i hope your not some kind of stalker. But thanks for keeping an interest in my progress.
Its actually 1800hrs / CPL and PPL instructor / FO and most importantly, 36
Its actually 1800hrs / CPL and PPL instructor / FO and most importantly, 36

Joined: Jul 2003
Posts: 1,092
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From: uk
Tapping the prop may have the same effect as railway wheel tappers, might be a way of detecting cracks.
Steam engines and old wind up record players use two bob weights spinning around a shaft that lifts a valve to govern the flywheel speed, in the case of steam engines.
As for the prop, use the analogy of wood screws.
Take off and climb takes a lot of effort, like trying to screw into hard wood, so you would use a fine thread screw, so that the effort required to turn travels a small distance.
Whereas screwing into chipboard takes little effort so the screw has a coarse thread, a bit like coarse prop setting in the cruise.
Steam engines and old wind up record players use two bob weights spinning around a shaft that lifts a valve to govern the flywheel speed, in the case of steam engines.
As for the prop, use the analogy of wood screws.
Take off and climb takes a lot of effort, like trying to screw into hard wood, so you would use a fine thread screw, so that the effort required to turn travels a small distance.
Whereas screwing into chipboard takes little effort so the screw has a coarse thread, a bit like coarse prop setting in the cruise.
Joined: Dec 2003
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From: Massachusetts Bay Colony
Are you ALL numpties???
I can't believe so many of you haven't gotten the joke! OK, I had to read it twice to get it but variable PITCH...different NOTES...think musical "pitch" here, gang.
I'm not sure if the joke was really that clever or you're all really that thick.


Pitts2112
I'm not sure if the joke was really that clever or you're all really that thick.



Pitts2112
Joined: Jan 2001
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From: The Burrow, N53:48:02 W1:48:57, The Tin Tent - EGBS, EGBO
I can hazard a very good guess as to the identity of the CAA examiner involved as he repeated the joke to me only a few days ago.
It's one he uses to help his prospective victims relax a bit during the exam.
It's one he uses to help his prospective victims relax a bit during the exam. 



