Constant Speed for O-300 possible
Moderators: GAHorn, Karl Towle, Bruce Fenstermacher
Re: MT
About a year ago I spoke to MT about their electric props. They have one set up for the 172. For the 8 bolt hub they have nothing but did quote about 2 years and 50k to get a prop developed for the 170. They offered to sell the 172 prop but you would have to get a one time STC and manufactuer a hub adapter. The cost a little over 10k, not including the cost of getting the STC or the hub adapter.
Doesn't MT use prodominately either wood or composite construction? Wood (the ultimate composite) and composites have maintenance/inspection issues. But one reason experimental types like them is they also dampen vibrations and typically do not have the stress considerations of all-metal designs. All-metal props must undergo pretty extensive/complicated vibration testing to avoid long-term failure modes. (It's one reason the Sensenich prop has rpm-range cautions.) I wonder if that MT 172 prop isn't wood/composite?)
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
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funseventy
- Posts: 230
- Joined: Fri Oct 25, 2002 11:46 pm
George,
You are right about MT being composite. I have talked to them as well. I wouldn't take them out of the running either but let's see what comes up.
Blueldr,
I don't think you have the pulse of this cult group if you think a 182 is a step up from a 170. That's like a heterosexual switching teams!
Kelly
You are right about MT being composite. I have talked to them as well. I wouldn't take them out of the running either but let's see what comes up.
Blueldr,
I don't think you have the pulse of this cult group if you think a 182 is a step up from a 170. That's like a heterosexual switching teams!
Kelly
Hi Kelly,funseventy wrote:George,
You are right about MT being composite. I have talked to them as well. I wouldn't take them out of the running either but let's see what comes up.
Blueldr,
I don't think you have the pulse of this cult group if you think a 182 is a step up from a 170. That's like a heterosexual switching teams!
Kelly
Blueldr said the 172 drivers would step up to a 182! Hasn't ever sounded like Blueldr is anywhere close to switching teams.
Joe
51 C170A
Grand Prairie, TX
51 C170A
Grand Prairie, TX
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funseventy
- Posts: 230
- Joined: Fri Oct 25, 2002 11:46 pm
Joe,
Thanks for straightening me out! It sounded like a rant at first and so that was how I read it at the end. Woops, my bad!
Blueldr,
I am very sorry about the comment I made and to make it up to you if front of everyone I would like to express how good you look in that dress! HA!
But seriously I'm sorry I read it wrong and I'll put you back on my list of good people!
Kelly
Thanks for straightening me out! It sounded like a rant at first and so that was how I read it at the end. Woops, my bad!
Blueldr,
I am very sorry about the comment I made and to make it up to you if front of everyone I would like to express how good you look in that dress! HA!
But seriously I'm sorry I read it wrong and I'll put you back on my list of good people!
Kelly
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BloomerJohn
- Posts: 55
- Joined: Mon Apr 22, 2002 3:28 pm
MT Props are laminated wood core that is wrapped in a protective composite. They have done exhaustive dynamic testing and found extremely limited instances of harmonic vibrations (mostly on very high compression, electronic ignition motors). They are lighter, have a much lower polar moment and have no TBO. Prop strikes w/ the MT typically shear the blades at the impact point and do not subject the engine to 'sudden stoppage'. Damaged blades are sent bact to the factory and are stripped and rebuilt to new demensions.
The 172 MT prop is avail in 2 blade or 3 blade versions. It is tested and rated up to 165HP. Larry (our U.S. MT Sales Rep) has sent a request to MT for info on a hub that would bolt on to an O-300. You are correct on pricing and time for an STC. Question to you AI's? Could you get a field approval and 337 for the use of the prop??
The 172 MT prop is avail in 2 blade or 3 blade versions. It is tested and rated up to 165HP. Larry (our U.S. MT Sales Rep) has sent a request to MT for info on a hub that would bolt on to an O-300. You are correct on pricing and time for an STC. Question to you AI's? Could you get a field approval and 337 for the use of the prop??
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BloomerJohn
- Posts: 55
- Joined: Mon Apr 22, 2002 3:28 pm
Here is the url of the MT Propeller site that details the operation of their electric props. Still waiting on word of a hub that would bolt to an O-300.
http://www.mt-propeller.com/en/electrvp.htm
http://www.mt-propeller.com/en/electrvp.htm
Both Lycoming and Continental REQUIRE engine teardown/sudden stoppage inspections if the prop requries removal for repair. It matters not if the prop is metal, wood, or putty. If you have insurance, and if you do not perform that teardown inspection...guess whose money you are saving. (Hint: It ain't yours.)BloomerJohn wrote:Prop strikes w/ the MT typically shear the blades at the impact point and do not subject the engine to 'sudden stoppage'.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons.
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BloomerJohn
- Posts: 55
- Joined: Mon Apr 22, 2002 3:28 pm
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BloomerJohn
- Posts: 55
- Joined: Mon Apr 22, 2002 3:28 pm
MT Propeller has a hub for the Cont O-300 / C-145 engine for use with their Electric 2-blade prop. The hub fits the 541 series crank (newer). An adapter is avail for the SA-3 style flange.
This prop is 'certified'., but no STC exists. It could be put on and used on a 170 only as EXPERIMENTAL.
We would need 15 orders confirmed at $9000 ea to begin STC work.
John
This prop is 'certified'., but no STC exists. It could be put on and used on a 170 only as EXPERIMENTAL.
We would need 15 orders confirmed at $9000 ea to begin STC work.
John
Hi John,BloomerJohn wrote:MT Propeller has a hub for the Cont O-300 / C-145 engine for use with their Electric 2-blade prop. The hub fits the 541 series crank (newer). An adapter is avail for the SA-3 style flange.
This prop is 'certified'., but no STC exists. It could be put on and used on a 170 only as EXPERIMENTAL.
We would need 15 orders confirmed at $9000 ea to begin STC work.
John
I'm curious about the costs involved in getting an STC. I assume there may be some manufacturing costs if the STC involved new or modified parts and then life cycle testing and performance testing of said new or modified parts. Aside from that what are the additional costs involved? Is there a standard fee one must pay the FAA to apply for an STC?
As an aside, I checked with xpmods (they make pponks gear legs) not too long ago about getting 140 gear legs and they were after a similar commitment, 10 orders at $5k for new steel gear legs, 10 orders at $8k for titanium gear legs.
tye
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BloomerJohn
- Posts: 55
- Joined: Mon Apr 22, 2002 3:28 pm
My MT source owns STC's for nearly a dozen A/C to use the MT prop. Each one took nearly 18 mos to get and between 40K-50K. FAA is real picky on tests to grant 337 on props. A tremendous amount of vibration, stress and endurance testing must be done, both on test stands and on actual A/C of the type being applied for. He would get the 337 with 15 confirmed orders. He would be at about a breakeven point at that number. Many peolple have asked him to get 337 on various aircraft, but usually this interest ends with the request for a non-refundable deposit from 15 buyers.
John
John