three blade prop for M-5-235C

[pitts10ch]

Hi all,

Is there an STC or method of putting some three blade prop on an M-5-235C with an O-540J1A5D? If so, which one? Thanks very much.

Chris

By the way all, the bird is for sale on Barnstormers Red and white and 2000 restoration. Thanks again.

[YELLOWMAULE]

Calling TomD.....

[TomD]

One Mr. Jeremy Ainsworth has the STC for a Mac. three blade.

I have one hanging in front of my O-540J1A5D and love it.

TD

[g5280]

I got my 3 blade prop about 8 maybe 10years a gohttp://www.mauleak.com/ that would be Jeremy

[pitts10ch]

What type of performance changes can one expect from the addition of a three blade prop on the M-5-235? Thanks guys.

CH

[maules.com]

Pros: Quieter for pilot and passengers and those on the ground, smoother for pilot, rivets, welds, electric connections, instruments, etc so less fatigue. Faster acceleration to wing lift speed and greater climb rate in vx best angle over the obstacle, then at vy best rate and cruise not much difference. Same cruise speed in standard configuration but slightly faster in dirty configuration with floats or big bushwheels.
Sex appeal.
Cons: Cost more to buy. Cost more to repair if damaged. Weighs 16lbs more than 2 blade. Not as much reserve metal to keep filing off if working in larger agregate rock bars or beaches. Harder to prop start.
Personally I use 3 blade for smooth and quiet and initial thrust.

[maules.com]

The above comparisons are versus the 81 inch McCauley two blade which is superior to the older 81inch Hartzell and far superior to the old 78inch Hartzell.

[benflyn]

Jeremy,

Is there any otions for a M5-210tc outside the hartzell 78"?
Had any experience with the MT's?

Thanks!!

Butch

[maules.com]

I know of no other prop but that does'nt mean there is'nt one. Maule was testing an MT on the 180 and 235 at one time but I think cost was restrictive and the idea died away or is on back burner.

[UP-M5]

so it is time for me to buy a new prop, and i want to make the most educated choice that i can. i have talked to lots of people about this, but thought i would throw it out to everyone here. i am narrowed down to the 3 blade mac or the 2 blade 81" mac. the 2 blade 84" mac wouldn't be legal on 8.50 tires that i run in the winter with my wheel skis- as far as i know. if i am incorrect about this please let me know.
so i initially was set on the 3 blade due to the high sex appeal, but the more i talk to folks operating them up here (AK) the more i am leaning toward the 2 blade 81incher. the float guys are having good luck with the 3 blade, and i hope to be on floats in the not too distant future, but i am in the gravel and rocks most of the time now.
i know price difference is a couple grand. but i have a mint condition spinner assembly for a 3 blade already, and that could offset that difference.
so lets hear it 235 owners- anyone have experience with both or either??? which prop has the highest thrust? i have heard different answers depending on who i ask

[a64pilot]

I have the Hartzell Scimitar. Can't comment on the Mac. I only fly on wheels. Gut feeling is that there isn't much difference between it and the 2 bld Hartzell performance wise, except the three blade costs more and weighs more. The three bld is smoother though. I got mine for a little less than the cost of a two bld from Hartzell as it had 6.5 hours on it. The cost being less and maybe it will help re-sale one day is why I bought it.
At least with the Hartzell, if your expecting a big performance gain then you will be disappointed.
I think most people will think there is an increase in performance, based mostly because of all the money they spent. If you are buying it mostly for the looks then you won't be disappointed.

[Flyin'Dutch']

From my understanding Jeremy's Januarly post sums it up neatly.

[210TC]

I was talked into a four blade on my rocket. Smooooooth lots of clearance and the engine will accelerate like a racing engine. Got good high altitude performance, lost elsewhere.
If I had it to do over again I WOULD UNDER NO CIRCUMSTANCES CONDUCT BIZ WITH MT PROP AGAIN. They set a new standard for the worst words in the dictionary. GET everything in writing or you will be sorry. Check for law suit's against MT for FALSE and deceptive practices.
YOU HAVE BEEN WARNED
Remember, LONG props climb the best. Thrust test are easy to do and don't lie.

[maules.com]

An addendum to 'long props climb the best'.....but only as long as the tip speed remains below the speed of sound.
For example the 86" two blade McCauley I developed for the 2400rpm O540J engine can work well, but at 2700rpm on the IO540V 260hp it is too fast at the tip and must be cut down.