what hartzell propeller?
 

Hi all,

i have an rv9a ready to install a brand new AEIO360M1B. ( i know this engine is overrated for this aircraft, but i got a really good deal and i cant miss it). The question now is, can someone help me to decide wich hartzell prop should i buy?

Henrique Castro
RV9A PP-XRV

blended airfoil hartzell 74" CY2R would be my choice, but then again with all that extra power a sensenich fixed pitch would do the trick. For what its worth ,the sensenich is just as fast as the constant speed . Neither of which will be utilised to their maximum on a RV9 airframe [speed limitations]

At one point
 

At a higher RPM and subsequent higher fuel burn. Agree the Sensenich is a great prop but apples and apples.


Yes the blended C2YR-1BF/F7496 is the best you can get, for overall performance. For a Fixed pitch, the Sensenich is a great prop for the money. The constant speed Hartzell will cost 5 grand more, but overall performance will be better. However since you are adding a heavy engine in a RV-9a, which was designed for a O-320, you may use the Sensenich to keep the with down a little. With both the IO-360 and Hartzell C/S prop, you are going to be 30-50 lbs heavier on the nose.


There is no Lycoming AEIO-360 M1B that I know of. Is it a IO-360 M1B?

If there is a AEIO-360 M1B, aerobatic engines "AE" are heavy engines, and would not be a great choice for a non-aerobatic RV-9a.

George

Aeio-ei-ei-o
 

As I understand it, all it takes to make an IO into an AEIO is to add an inverted oil system, which is all external to the engine. Lycoming supply a Christen system as it is certificated. The builder can do this at any stage if he desires using any of the aftermarket inverted oil systems.

I browsed the Lycoming 'site once and found an IO-360-M1A listed. It is similar to the M1B but had a front mounted governor. I was interested as I was looking for an aerobatic engine and a front mounted governor is preferable due to less prop surging with oil pressure fluctuations, plus one less external oil line to crack. Has anyone ever seen one? Were they ever made?

RV4 VH-PIO

What engine?
 

Hi Henrique,

So, you're upgrading your 9a from a IO240 to a AEIO360M1B? That will be quite a jump! No chance of selling the AEIO360M1B and getting an io320? If you stay with the heavy AEIO360M1B you may want to seriously consider a lightweight composite prop, like the MT or the Catto. Most people report great results with these light props. If you stay with the AEIO360M1B you'll probably need to add some ballast in the tail. Battery in the back is a good idea, or just some lead ballast right under the VS.

hey everyone,

Thansk for the reply. hey mickey, it?s possible to change, but the agreement that i got requires me to keep the engine for at least 2 years before selling it (brazilian laws, blargh!!!) anyway, believe or not , i bought this engine cheaper than i sold my IO240. For this, its better to keep this engine for a while.

About sensenich prop be the best choice, isnt the hartzell provide me better gas mileage the a sensenich?

Yea I guess so
 

News to me to me, but I looked it up and it seems adding the aerobatic kit is all that makes it different than the n on aerobatic model, as you say. I thought the crank shaft was heavier. As far as forward prop gov, I never have had surge issues with a rear mounted one. I agree no tube is nice, but working around the forward gov is a pain in the RV's and may need a cowl Bump for clearance with a tight cowl. G
Do the math, the hartzell might save on average 0.45 gal/hr. At $3.00/gal and $5000 more for the c/s set-up you, would need to fly 5000 /(0.45 x 3.00) = 3700 hours to pay for the prop. OF course you need to overhaul the prop at 2000 hours which is more than a fixed by a factor of 2 or three.

So gas savings is going to take a while to pay for it self and not the reason I prefer them. However takeoff and climb performance will be much better. In cruise lower RPM is less vibration and noise. A constant speed is better overall, like fuel injection is better than a carb but at a price premium. I have a O-360a1a with a Hartzell and love it. G