What is an electric variable pitch prop?

A more common variable pitch prop is the "hydraulic" one which uses engine oil pressure to move the blades. An electrical one uses a small motor to change the pitch. Not uncommon on older Bonanzas.

The MT prop control is the small knob on the panel hanging below the panel to the left of the throttle (directly below the takeoff/landing checklist placard).
 
flyingron said:
A more common variable pitch prop is the "hydraulic" one which uses engine oil pressure to move the blades. An electrical one uses a small motor to change the pitch. Not uncommon on older Bonanzas.

The MT prop control is the small knob on the panel hanging below the panel to the left of the throttle (directly below the takeoff/landing checklist placard).
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Pretty much. I don't think they were ever common, but electric props were in use in the 30s and 40s. Grumman Wildcat used an electric prop too.
 
Is it a constant speed prop, or just adjustable pitch?
 
Constant speed, it comes with a little governor box.
 
That's an MT electrically adjustable prop. It allows the addition of variable pitch to planes that were previously fixed pitch. It's a neat concept. I believe it's constant speed, but haven't dealt with it much personally.

Hydraulically adjustable props are more standard. Early Bos had electric props. It will add some cost because it will be more expensive to overhaul than a fixed pitch prop, but you do get something for your money.
 
The MT is constant speed. It can come with either a simple "faster or slower" controller or one (like this one) where you set the RPM you want with a knob.
 
I have one.
http://www.mt-propeller.com/en/entw/pro_elec.htm
Mine uses the P-120-U controller in the panel:
5-10-2011013.jpg


In auto mode you just dial in the RPM you would like. In manual mode the RPM dial is non-functional and you use the right side toggle switch to go to "start" which is high RPM for takeoff and landing or push down for cruise pitch. It uses small brushes on the back side of the flywheel (just like for a de-iced prop) to send power to the servo motor in the prop hub which changes pitch.

The electric prop changes pitch slower than a hydraulic prop but works well.
 
Now that I think about it I have flown a Grumman AA5 with a MTV electric prop and the same P-120-U controller which mine has.
 
FORANE said:
Now that I think about it I have flown a Grumman AA5 with a MTV electric prop and the same P-120-U controller which mine has.
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How many of them are there? I thought the Tiger + electric prop combo was quite rare.
 
asicer said:
How many of them are there? I thought the Tiger + electric prop combo was quite rare.
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I have no idea. The only AA5 I have ever been in had one though. The guy was based at an airport where I had been working and he needed to re-position his plane but was out of medical. He asked me to serve as PIC for him.
 
Yeah......that was mine repositioned by Forane - thanks again!
There are a dozen or so MT-equipped Tigers about, I think.
The OP listed plane seems very well equipped and quite a bargain I would say.
The Sandel unit adds value as does the MT.
Jaguar cowling is well regarded in Grumman community, Power-Flow exhaust adds significant performance.
Altitude Hold could be added to the C-II.
Accident history?
Maintained by Ken Blackman in that part of country? - if so, jump on it!
 
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MickYoumans said:
The ones I've seen were just variable pitch and not constant speed. They used a motor to drive the pitch between the climb versus cruise settings, but nothing in between

http://www.ivoprop.com/inflightmagnumodel.htm
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Actually it is everything in between! I had one of these on my RV for a while. After you level off, you manage RPM manually with the switch. In level flight you can have any RPM you want (within the pitch range of the prop)..When you let go of the switch, the prop stays at that setting - no automatic adjustment, so if you start a climb or descent, the prop acts like a fixed pitch prop (because it is, until you hit the switch). IVO makes a constant speed controller, but I never got one. Now I have an MT and as noted previously, it does have a constant speed mode. The electric motor is not as fast as a hydraulic prop, but other than that it works the same.
 
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