rsieminski

The plane weighs almost 6 lbs, and I want as much speed as I can get. Can I, should I run this prop, or is there a better one?

MMallory

My Feedback: (1)

For a 6 lb. plane you might want to step up to a .60 sized engine. The only way to tell an engine will turn a prop is to run the recommended prop and check the rpm, then run the questionable prop to see if there is a significant drop in rpm. Most .46's would run closer to an 8x10 (if you want a 10 pitch). Personally I would try a 9x9 first.

Mark

RSands

I run one on a K&B .48 with a tuned pipe. Hauls my DD around much quicker than the 9x8. Without a tuned pipe though, the 9x8 may work better. Also, the dust is ~2.5 lbs and very low drag. A 10x7 may prove to be the fastest depending on your planes design.

rsieminski

I don't necessarly need a 10 inch pitch, just more speed. Right now it'll spin an 11x5 at 15.5-6k. If it runs wot much less than 14.5K, midrange seems to richen up. I'll see what it does with a 10X7. I don't want to have less than 1:1 thrust:weight ratio.
What brand of prop does everyone prefer, APC or MA? I find the MA spin up faster and spin higher rpm, without visible difference in flight performance.

RSands,
Any idea what rpm it runs with that prop?

Cyclic Hardover

My Feedback: (3)

Well I am running a 9/7apc on a 4lb Shrike turning 17k at 130mph on a simple TT46pro!. Your asking for way to much out of a .46 size engine on a 6lb plane. What kind of plane is it?

RSands

I've not tached my motor, but APC's blow the MA's away in terms of performance/efficiency.

Razor-RCU

My Feedback: (50)

What kind of plane, and what kind of engine...?

rsieminski

It's a piped Tower .46bb, on a spad. It'll turn an 11x5 at 15.6K+. On 15%N, 20%O (80/20). It seems very strong for a .46.
The plane is just too draggy. I cut the span down to 42" from 48", and streamlined it a bit. I tried a 10x8 today, but didn't tach it. It seemed to be faster visually though. Acceleration really suffered though. I weighed it yesterday on an accurate scale....gulp 6.6Lbs! I shaved a little more than 6 oz with the wing shortening.
I also tried an 11x7, acceleration was better but not as fast as the 10x8.

JohnVH

My Feedback: (38)

Ive got a 9x7 or 8 on a DD with a OS.46, It sounds awesome in a full throttle dive!

Flyboy Dave

My Feedback: (21)

Nope....9-8...tops...( 9-7 )better... ( if ya want all the revs out of it) 10-6 is good too, but even a 10-7 will reduce the revs...