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MT Electric

gvgoff99

gvgoff99

Well Known Member
Has anyone had any experience with putting an MT Electric CS prop on a Lycoming O-320 (160HP). I have a Lycoming O-360 E2D (upgraded to 160 HP) which does not have an accessory case that will take the CS governor, nor is the crank case drilled for the oil return line so without MAJOR (read "$$$$") I am stuck with either leaving it with the Catto FP or for a CS using an electric. I have about 260 hours on the engine so I kind of hate to junk it at this point unless I could sell it, the cowling and prop for about $20,000. I doubt that would happen in this economy.
The Catto is good in cruise but in hot Texas the climb is anemic.

Paying 12G for the MT seems to be a lot but I am also thinking of moving to Durango, CO. The mountains make me reflect on the poor climb above 8000'.:eek:

Does anyone have the 160 HP with MT electric CS combo and thoughts on if it is a big improvement or not? Thanks
 
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electric CS MT propeller on 140 hp engine

gvgoff99 said:
(Stuff Cut)

Does anyone have the 160 HP with MT electric CS combo and thoughts on if it is a big improvement or not? Thanks
Click to expand...

I have an electric CS MT propeller on my RV-3.
I also have flown my RV-3 with a fixed pitch Warnke propeller. (A very nice performing fixed pitch propeller.)

My take off roll is significantly reduced with the CS propeller.
And I get to choose the engine RPM for cruise. I don't think it gets much better than this.

Jim Ayers
RV-3 sn 50
LOM M332A engine - 140 hp (2700 RPM & 35" MAP)
using an electric CS MT Propeller
 
MT7 with Lycoming?

No question, a constant speed prop will improve take off and climb performance be it a MT electric or any other CS propeller. The MT7 with a PSRU and the Subaru H6 was most impressive on take off and initial climb, noticeably better than with a fixed pitch CATTO. But of course the cost and weight difference is quite noticable also.

What of the possible use to the MT7 with a Lycoming engine? There are some MT7's on the market the result of guys moving on from the Subaru experience and at a reasonable price. It is however my impression the MT7 is not suitable for even the 0320 due to vibration issues. But MT could do a vibration survey if anyone wanted to go that route and convince MT to do it. Their engineering people d0 come to the U.S. to deal with technical issues. The MT7 was surveyed with 2.5 and H6 EGG engines.

Just a thought on the issue of acquiring a CS prop. The MT7 is set up for 6/7 inch bolts which would go with the 0320. But the -7 version is quite a bit lighter than the Lycoming certified versions of the prop.
 
MT Electric prop practical info

I understand the MT electric prop is much slower to change pitch than a conventional hydraulic setup. In practice, is this a big deal in an RV?

Some more things I'm wondering about:
What's the static RPM at flat pitch and full throttle? Are there hard limit adjustments to set this?
How well does the prop speed regulate itself on takeoff, and how slowly must you advance the throttle?
Is it practical to leave the prop set to CS mode, or do you find yourself switching between modes in different phases of flight?
Has anyone tried rigging the controller to a conventional pitch lever or knob?
Any comments on what to expect of this prop in aerobatic maneuvers?
How reliable is this prop, particularly with regard to the commutator ring?

Any practical input on the care and feeding of this prop would be greatly appreciated, but please save the comments on FP vs. CS. That seems to have been covered ad nauseum in other threads!

Thanks,

M
 
foka4 said:
I understand the MT electric prop is much slower to change pitch than a conventional hydraulic setup. In practice, is this a big deal in an RV?
Click to expand...

Should not be for instrument flying. Can easily result in prop overspeed doing aerobatics.
 
Hi,
I replaced a wood prop on my RV3 with a MT electric. FYI Jim Ayers was the dealer for MT and he put together a group buy, it was about $7800 including freight. It came totally complete, mounted spinner, etc.

I ended up rebuilding the instrument panel to make space for the controller and MP gauge though. The controller works exceptionally well by the way, in use, the rpm does not vary, it behaves just like a hydraulic prop.

My weight stayed exactly the same, at the same time I installed an Odyssey battery and lightweight starter, the empty CG shifted about one quarter inch forward.

The performance was definitely different. Take off roll is reduced significantly. The push into your back on power application is noticeable! The cruise is quieter because you can run at lower RPM. Full blast as fast as you can go is the same , I did not gain any speed. But you really do not end up running at full throttle and 2700 rpm anyway. I get the same speed with less noise, and essentially the same fuel burn with the MT installed.

In the pattern, wow, that prop is a huge air brake on a light little airplane. Better keep the rpm up to 2000 while in the pattern up to short final or you will imitate the flight path of a brick. The airplane is no longer a glider at idle thrust. This is detrimental in my view, although you learn to live with it.

In 250 hours it has been 100% trouble free. Typical German engineering here.

Would I do it again? No, not enough improvement to worry about My airplane already climbed like mad, but I do not live at 8000 feet either.

If I were you, I would just fly your airplane like it is, or sell it and buy another with a constant speed already on it. Even in today's market you can make a trade like that for less than the cost of changing.

Good luck!
 
pvans said:
Hi,
I replaced a wood prop on my RV3 with a MT electric. FYI Jim Ayers was the dealer for MT and he put together a group buy, it was about $7800 including freight. It came totally complete, mounted spinner, etc.

I ended up rebuilding the instrument panel to make space for the controller and MP gauge though. The controller works exceptionally well by the way, in use, the rpm does not vary, it behaves just like a hydraulic prop.

My weight stayed exactly the same, at the same time I installed an Odyssey battery and lightweight starter, the empty CG shifted about one quarter inch forward.

The performance was definitely different. Take off roll is reduced significantly. The push into your back on power application is noticeable! The cruise is quieter because you can run at lower RPM. Full blast as fast as you can go is the same , I did not gain any speed. But you really do not end up running at full throttle and 2700 rpm anyway. I get the same speed with less noise, and essentially the same fuel burn with the MT installed.

In the pattern, wow, that prop is a huge air brake on a light little airplane. Better keep the rpm up to 2000 while in the pattern up to short final or you will imitate the flight path of a brick. The airplane is no longer a glider at idle thrust. This is detrimental in my view, although you learn to live with it.

In 250 hours it has been 100% trouble free. Typical German engineering here.

Would I do it again? No, not enough improvement to worry about My airplane already climbed like mad, but I do not live at 8000 feet either.

If I were you, I would just fly your airplane like it is, or sell it and buy another with a constant speed already on it. Even in today's market you can make a trade like that for less than the cost of changing.

Good luck!
Click to expand...

THANK YOU! Exactally the info I hoped someone had to share. Excellent write up and very informative. :D
 
breister said:
Can easily result in prop overspeed doing aerobatics.
Click to expand...

I thought you could set these to "manual mode" override to just keep a fixed pitch, with direct control. Would that work better for acro? (And gliding if need be, to allow courser pitch at idle or no power.)
 
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Originally Posted by breister
Can easily result in prop overspeed doing aerobatics.


DCat22 said:
I thought you could set these to "manual mode" override to just keep a fixed pitch, with direct control. Would that work better for acro? (And gliding if need be, to allow courser pitch at idle or no power.)
Click to expand...

You can set manual control, just move a switch from auto to manual and it is done.

Not a good idea for take off however. Did it one time. :)
 
Confirmed...........

I called MT and confirmed that the MT-7 is NOT suitable for use on Lyc 4-cyl engines. :( They do have other models that are suitable.:cool:

David-aviator said:
..........What of the possible use to the MT7 with a Lycoming engine? There are some MT7's on the market the result of guys moving on from the Subaru experience and at a reasonable price. It is however my impression the MT7 is not suitable for even the 0320 due to vibration issues. But MT could do a vibration survey if anyone wanted to go that route and convince MT to do it. Their engineering people d0 come to the U.S. to deal with technical issues. The MT7 was surveyed with 2.5 and H6 EGG engines.

Just a thought on the issue of acquiring a CS prop. The MT7 is set up for 6/7 inch bolts which would go with the 0320. But the -7 version is quite a bit lighter than the Lycoming certified versions of the prop.
Click to expand...
 
PCHunt said:
I called MT and confirmed that the MT-7 is NOT suitable for use on Lyc 4-cyl engines. :( They do have other models that are suitable.:cool:
Click to expand...

Curiously, the MTV-7-F/170-09 was certified in Europe in 1992 on the Cessna 152 and Piper Tomahawk with the 0235 engine. That certification did not make its way across the Atlantic.

The MT-7 coming up for sale over here is the MT-7-C/183-51, the unit Jan Eggenfellner imported. I do believe MT engineered it to match the original 2.5 engine. They did a vibration survey to confirm its integrity. Same must have happened with the 152 and Tomahawk back in '92.

That prop replaced the Quinti with Warp Drive blades in the EGG world. Both are very good propellers, I've flown behind each with Subby - but not with Lycoming.

Too bad we don't have more electric choices with the Lycoming. The systems are lighter and work well. The only issue I had with the MT was the brush blocks dropping off the rails one time due to an improperly designed bracket to hold them. Those rails and blocks are very similar to prop de-ice systems which have been around for years.
 
When I called MT, I specifically asked about an O-320 E2D, 150HP. I may have over-generalized my comment below.
 
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