# Explaning how a adjustable pitch. constant speed prop works:

#### CaptainChris87

##### New Member
I was wondering how you guys would explain in the simplest way how an adjustable pitch/contant speed works to a student. This is for me to be able to do the same back to the student and also for me to gain an understanding of how exactly the Nitrogen charged cylynder, speeder spring and counter weights work when you push and pull the prop handles.-thanks

#### moxiepilot

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

There's really only 4 things to explain and then connect:

1. the speeder spring pulls the flyweights inward when there is a lack of centrifical force
2. the flyweights move outward (or to a more flat plane) when centrifical force is applied
3. the flyweights are connected to the pilot valve, so when they move, the pilot valvel moves
4. the pilot valve controls the amount of pressure to the hub

make a simple drawing and it should come together

#### majorityof1

##### New Member
Re: Explaning how a adjustable pitch. constant speed prop wo

A good article written by John Deakin can be found here: http://www.advancedpilot.com/downloads/prep.pdf There are several articles in that link. The first article is 'Manifold Pressure Sucks' which is a great article about manifold pressure. The second article in that link is about props. That is a general outline of how I explain props.

#### holyshirt

##### New Member
Re: Explaning how a adjustable pitch. constant speed prop wo

I usually explain like this..

"When prop lever is pulled back, oil is fed into prop hub. As oil enters the hub it causes a piston to move forward and cause the blades to change pitch. The RPMs are maintained via a governor. The governor works like this..." and then thats when I start to draw it out.

#### Sidious

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

A good article written by John Deakin can be found here: http://www.advancedpilot.com/downloads/prep.pdf There are several articles in that link. The first article is 'Manifold Pressure Sucks' which is a great article about manifold pressure. The second article in that link is about props. That is a general outline of how I explain props.

Just printed and read those articles and I have to say they are great. He explains things in a conversation tone which keeps everything interesting and I'm not afraid to say I learned a few things, especially the Manifold Pressure one.

Thanks

#### Blackhawk

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

A good article written by John Deakin can be found here: http://www.advancedpilot.com/downloads/prep.pdf There are several articles in that link. The first article is 'Manifold Pressure Sucks' which is a great article about manifold pressure. The second article in that link is about props. That is a general outline of how I explain props.
He has some great articles on aircraft systems that I pass on to primary students.

#### USMCmech

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

A good article written by John Deakin can be found here: http://www.advancedpilot.com/downloads/prep.pdf There are several articles in that link. The first article is 'Manifold Pressure Sucks' which is a great article about manifold pressure. The second article in that link is about props. That is a general outline of how I explain props.

Deakins' articles about MAP, & RPM are hands down the best descriptions out there. I simply copy his presentation and walk my students through it.

#### beechpilot84

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

Also explain about how the blade angle changes the speed of the prop. Ya know the whole thrust vs. drag thing.

#### CFmike

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

That article posted up earlier is great! Im still reading my way through it. Very intersting.

#### PFGiardino

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

I start by talking about the disadvantages of a fixed pitch prop and how it would be "real nice" to be able to change the angle.

Then I talk about variable pitch props.
Then I talk about constant speed props.
Then I show them how ours works.
Then I ask them how ours works.

Seems to work out alright.

#### Blip16

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

A good article written by John Deakin can be found here: http://www.advancedpilot.com/downloads/prep.pdf There are several articles in that link. The first article is 'Manifold Pressure Sucks' which is a great article about manifold pressure. The second article in that link is about props. That is a general outline of how I explain props.
where are the rest of the articles?

#### USMCmech

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

where are the rest of the articles?
Go to Avweb, and search.

#### majorityof1

##### New Member
Re: Explaning how a adjustable pitch. constant speed prop wo

BuickCFI, there are three articles in that link: Manifold Pressure Sucks, Those Marvelous Props, and Mixture Magic. All of these articles are written by John Deakin in his Pelican's Perch series on avweb.com. Or you can follow this link or type in: http://www.warmkessel.com/jr/flying/td/jd/index.jsp to find just about all of his articles.

As a warning warmkessel is a random family's webpage. If you go to the 'Home' page of warmkessel and then to Barry's page, you may laugh yourself silly.

Cheers!

#### Blip16

##### Well-Known Member
Re: Explaning how a adjustable pitch. constant speed prop wo

BuickCFI, there are three articles in that link: Manifold Pressure Sucks, Those Marvelous Props, and Mixture Magic. All of these articles are written by John Deakin in his Pelican's Perch series on avweb.com. Or you can follow this link or type in: http://www.warmkessel.com/jr/flying/td/jd/index.jsp to find just about all of his articles.

As a warning warmkessel is a random family's webpage. If you go to the 'Home' page of warmkessel and then to Barry's page, you may laugh yourself silly.

Cheers!
thanks a lot!