[STEVE]

STEVE on March 6, 2022 at 10:55 am #21273

I believe the MT is more expensive than either the Hartzell or McCauley. I suggest you call a prop shop that sells MT props, to see what kind of deal you can work out using your existing prop as a trade in.
McFarlane Aviation is now the go to spot for MT prop information.
Steve

[Mick Kennedy]

Mick Kennedy on March 2, 2022 at 4:34 pm #21267

No problem Steve

My main concern was the durability of the MT working out of unimproved (gravel/grass etc) strips. I have had an experience of a 3 bladed MT on a F1 Rocket beginning to delaminate on the tip due to moisture ingress.

All advice on any of the three options is appreciated. Cost is also a consideration. Any idea what the MT is worth? If anyone has done the 3 blade conversion (McCauley, MT or Hartzell) I would be interested to hear of your experience, performance numbers and price.

Mick

[STEVE]

STEVE on March 2, 2022 at 10:38 am #21264

Hi Mick,
OOPs I mis read your question.
If you decide to install the three blade Hartzell you will lose 32 pounds of useful load. The McCauley three blade weighs 7 pounds more than the Hartzell.
The Hartzell three blade is 76 inches so no ground clearance will be gained if you replace your two blade with the Hartzell; the McCauley is also a76 inch diameter so no gain.
The TBO for the Hartzell three blade is 2400 hours/5 years; the McCauley is 2000 hours/6 years.
Hartzell cites these reasons for choosing its three blade over the McCauley: lower price and longer TBO.
Advantages over the two blade are cited as better take off and climb performance.
The one drawback that’s rarely mentioned when choosing to replace a two blade with a three blade is the additional cost to overhaul the three blade.

For what it’s worth, I have a two blade Hartzell on my Comanche and it’s been fault free.
That’s all the personal experience I have with these choices.
Let me know if you have further questions.
Steve

[STEVE]

STEVE on March 2, 2022 at 10:21 am #21263

Hi Mick;
The MT three-bladed prop has a smaller diameter (74 inches) than your present two-bladed prop (76 inches) so unless the MT has a larger disc than the two bladed disc, you’ll gain some ground clearance there.
I have spoken with the US rep for MT props and he showed me some videos that demonstrated the the nickel-cobalt leading edge is very tough; much more resistant to rock damage and rain erosion than an aluminum bladed prop.
A local friend has installed an MT prop on his Comanche 250 and has told me how smooth it is.
One interesting point is that the MT prop is much lighter than an aluminum prop assembly, this makes starting easier (spins faster) and the engine shut down is very abrupt since there’s no “flywheel” effect from the weight of the prop.
Go to http://www.flightresource.com for more information.
Let me know what you decide.
Steve

[Mick Kennedy]

Mick Kennedy on March 2, 2022 at 3:30 am #21262

Hi
My 2 blade props are up for overhaul soon and I’m looking for any info from anyone who’s upgraded to 3 bladed.
I’m concerned about the MT for the low clearance for some of the strips we will operate from. I am wondering about the pro’s and con’s of the McCauley v’s Hartzell top prop.

Any advice would be appreciated