Doug Rodrigues

Active Member
Does anyone have any comments about mounting a full feathering Hartzell prop from a Twin Beech Travel Air to a O-360A1D on an RV-8? The Travel Air cruise speed is about the same as an RV-8....I think? Don't know about the prop governer though?:confused:
 
Does anyone have any comments about mounting a full feathering Hartzell prop from a Twin Beech Travel Air to a O-360A1D on an RV-8? The Travel Air cruise speed is about the same as an RV-8....I think? Don't know about the prop governer though?:confused:
Having a full feathering prop would buy you a small amount of glide performance improvement, but adds a new failure mode. If the prop governor fails, the prop will feather. Personally, I would prefer to not have a feathering prop, unless I had a multi-engine aircraft.
 
It's a good deal.....but....

I've been talked out of it. Too many unknowns and maybes, plus no aid in slowing down with the power pulled way back. It was just a consideration of getting a prop cheap and into the air faster.
 
... plus no aid in slowing down with the power pulled way back.
As long as the engine is developing oil pressure, and the prop governor, oil line to prop, etc are serviceable, it will work like any other constant speed prop. I.e. the prop governor will control the blade pitch to attempt to keep the rpm at the selected value. So, if you pull the power back, the rpm will fall, and the prop will go to fine pitch. Exactly the same as any other constant speed prop.
 
Just got information from a Hartzell engineer....

**He said that the feathering prop is 20 lbs heavier that the Hartzell compact hub with the 7666 blades. Didn't know that.:eek:
 
You'll get a surprise when you accidently run out of gas on the right side and it feathers before you can switch. Just hypotheticals but I really don't think its a good idea to have a fully-feathering prop on a single-engine piston.
 
Won't feather by itself

You'll get a surprise when you accidently run out of gas on the right side and it feathers before you can switch. Just hypotheticals but I really don't think its a good idea to have a fully-feathering prop on a single-engine piston.

Doesn't work that way, you would have to pull prop control all the way back to feather even if the engine is just windmilling. Otherwise, the prop would feather every time you shut the engine down.

John Clark ATP, CFI
RV8 N18U "Sunshine"
KSBA