I understand the first number is the length and second is pitch,but is a 11x3 pitched more than a 11x7 or less? What are the advantages and drawbacks to more and less pitch? I have a Hanger 9 Tribute 36 and an OS .40 La, I would like to have th ability to hover and assume you want the most pitch that your engine can spin without losing power??????????

The pitch is how far the prop will move forward in theory in one revolution. An 11 X 3 will move forward 3" for each revolution while an 11 X 7 will move forward 7" in one revolution. The lower the pitch number, the better the prop will be for climb and vertical maneuvers. The higher the pitch number the faster the plane will fly. Guys who like to hover like the 3 - 4 pitch props while the racers like the 9 and above pitch props.

Hogflyer

11x3 is pitched less than an 11x7. For hovering, I was always told to go with a longer/lower pitched prop. This makes the plane less sensitive to throttle stick inputs. For example if you are hovering with a higher pitched prop you would be able to notice more change with one click up or down on the throttle stick. With a lower pitch more stick movement equals less movement, lets you get closer to the sweet spot.

I use higher pitched props when I want more speed like a pattern ship, etc. I had a .40 LA on my trainer and it seemed to be straining to swing a 10x6. So I would try something smaller in your case. I have a 10x4 on my .40 FP (pizza box) it hovers well, and the engine is still responsive.

This is written about boat props but it holds true of air props in many ways also
http://www.caravelleboats.com/propeller%20info.htm

GIVEN THE SAME RPM:

A higher numbered pitch and smaller diameter prop (9 x 8) will generate a higher top speed with less acceleration.

A lowered numbered pitch and large rdiameter prop (11 x 4) which will generate more acceleration and less top speed.

Pitch is the THEORETICAL distance (in inches) a prop will travel through the air in one revolution. The operative word here is THEORETICAL. The prop has an airfoil shape which will increase this distance, and a lot of slippage through the air which will decrease it.

Dr.1

Hi,

You will also notice that there are wide props made by APC. These are excellant for hovering and they make takeoff rolls faster and they act like air brakes when your landin. I use an 18x4W prop on my Twist 150 with a Saito 150 in it and the plane does more than I even expected it could. It hovers at less than 1/4 throttle and flies fast or you can creep around the field and land almost like an elevator if you have any head wind. 3D demand low pitch props. Thats what they are made for.

JMHO,

Gibbs

3D demand low pitch props. Thats what they are made for.

Actually, low pitch props were around and being used long before anyone even knew what 3D was. They work great on draggy planes, or on scale planes to limit top speed. They also made Full Competition Unlimited Class Fun Fly what it was. We did 3D-type stuff before anyone even knew what a Edge was.

Dr.1