I know that 10X5 eg. is a measurement and should perform the same in any brand but....but they are so differently shaped that I wonder if there is some advantage of one design over the other.

Thanks for the imput!

The apc tends to be a more high performance prop and the master airscrew more durable.When i first started flying and was scraping the prop alot on landings..i tended to like the ma prop becasue you could scrape the ground and not break it..however now that i would rather have the performance out of a prop a graupner or apc is what i prefer.I find the ma props tend to flex to much and although they are still fine to use the apc is better. The other side of the coin however is that in scale applications such as a war bird the ma prop looks more scale..Kieth

There is a BIG difference in prop brands due to material used, blade shape, and airfoil shape.

I switched to APC about 15 years ago, and I won't ever use anything else in composite props. I'm past the prop-strike-on-landing stage (usually).

The APC is much more efficient and accurately-pitched than most other composite props in the smaller sizes (under 16").

My wood prop usage is not critical, and I use modified Zingers on my 1/4 Fokker Dr.1 I shape the blades to a more scale outline, and add the metal shielding and logo labels for a more scale appearance. This hurts efficiency a lot, but the G-23 can still handle the plane at 14 pounds.

Dr.1

Just an FYI that 10x5 means its a 10 inch diameter prop with a 5" pitch, meaning for every revolution the prop will move forward through the air 5 inches (this is theoretical in practice its usually less)

The higher the pitch is like running higher gears in a car, it will go faster but not accelerate or pull as well. Lower pitch will accelerate better and hover better but not be as fast on the top end. Also engines make thier ideal power at a certian rpm so the trick is to find the diameter and pitch that put the engine in its accepable rpm range and performs the way you want it to for the airplane its on. For instance a war bird may have a smaller diameter high pitch for top speed where a 3d plane with have a larger diameter but a lower pitch for the same engine so it can hover and accelerate but not go very fast.

My first instructor told me when I asked him that ballancing the prop is not as critical in a .46 engine with a trainer. I am using the same engine I had in my trainer a TT .46 but in a Sea Bee. At what instance is it recomended to ballance the prop?

It may not be critical for a smaller prop..however i balance all my props...unbalanced props cause vibrations which loosen bolts and glue. Although you may not have to do it its pretty easy to do and anything that saves wear on a plane (especially the way i land) cant hurt ,Kieth

IMO, you should check the balance of ANY prop before installing it on an engine. Most composite props do not need balancing, but it's always wise to check. DO NOT sand one of these to balance it. Spray clear poly-u on the front side of the light blade. I also use poly-u on wooden props, although those may be sanded on the front side to balance. If a prop gently swings to the heavy side, it's ok to balance. If it drops to the bench with a THUD, return it.

Dr.1

PS I often take a simple Dubro teeter balancer with me to the LHS.

APC props are more efficient than a MAS prop. To get AN APPROXIMATE EQUIVELANT for power/performance, an APC 10x5 will provide slightly more power/performance than a MAS 10x6, but slightly less than a MAS 10x7.

The MAS props flex more than an APC, so thay are not as efficient. On the plus side, the MAS props are a lot more tolerant of prop strikes (prop hitting the ground ) than an APC.

Another thing to consider is the noise from the prop. Because APC are less flexible than MAS, they are several db quieter than MAS. This is something to keep in mind if noise levels are extremely critical where you fly.

So I would think that for landing training purposes the MAS is better for kissing mother earth with the model and the APC to get serious and take better deal out of a motor!