Whilrwind 200RV prop is non-aerobatic???

[ao.frog]

We've just installed my new WW 200RV prop, purchased via the group-buy here on VAF a few years ago.
That prop really is a beauty, a piece of art!

I noticed in the manual however, that the manual says it's non-aerobatic??

In my manual, marked REV 2009-1, page 2-3 it says: This 200RV propeller is a standard non-aerobatic hydraulic control propeller system

I must admit that I've not noticed this before, so shame on me, but is the 200RV really NOT suitable for doing acro with a RV?

The definition of acro in the airplane-world is when the bank goes above 60* and/or the pitch goes above 30*, but maybe the WW definition of acro is different one? Maybe "gentleman acro" (the one we can do in the RV's) is allowed? And "hard acro" (ala the typs the Extra's can do) is prohibited?

I'll contact WW regarding this matter ofourse, but this forum is normally so much quicker to provide info. (this made me VERY concerned.... yuk!)

So what's the verdict guys: have I screwed up BIG TIME and need to buy another prop, or is it something I've missed??

 

[cdmiller]

WW 200 RV prop works fine for most aerobatics

The WW 200 RV prop is designed to go to flat pitch if engine oil pressure drops. This can lead to an engine overspeed if the engine has a high power setting. True aerobatic props are designed to go to coarse pitch if oil pressure drops and therefore cannot overspeed. Some aerobatic maneuvers, particularly, transitions from positive to negative to positive G s can cause engine oil pressure fluctuations.

That being said, I have a WW 200 RV prop on my RV-8 and I have successfully flown aerobatics for more than 1350 hours without any engine overspeed problems. I do have a Christen inverted oil system, in addition to fuel injection. Most of my aerobatics consist of positive G maneuvers, including loops, various kinds of rolls, immelmans, cuban 8's, hammerheads, and split S's. I have done some inverted flight, without overspeed problems, but the RV-8 airfoil is not designed for inverted flight and the attitude of the nose is quite high to maintain level flight inverted. I mostly stick to positive G "inside" maneuvers.

I love my WW 200 RV propeller and would not trade it for any other type. It has performed flawlessly for me during the past 7 years, both during aerobatics and cross-country cruising. It is light and very efficient. I think that you are going to like your prop very much. And, it certainly works well for "gentlemans" aerobatics.

Dan Miller
RV-8. Superior IO-360 M1 with 9.2 to 1 pistons, fuel injection, one Lightspeed Ignition, one Slick mag, and a Christen inverted oil system.

 

[Russ McCutcheon]

To put your mind even more at ease I’ll ad to what Dan said.

Your “non-aerobatic” prop that reduces pitch with the loss of oil pressure is the same as 99.9% of what constant speed equipped RVs are using whether it be Hartzell, MT or WW. The true “aerobatic” props use weights to increase pitch against oil PSI, the weights are big, requiring a bigger spinner not standard to RVs.

Like Dan, lots of us are doing acro with these "non-aerobatic" props, your on the right track, no worries.

 

[ao.frog]

Sigh....

Hi guys.

Thanks for the replies. Good to know!

As I mentioned above, I also contacted WW regarding this matter and here's the reply I've just gotten from Jeremy Sutch at WW in Ohio:

The 200RV propeller can certainly be used for, and will perform very well doing what we refer to as “gentlemen’s aerobatics.” Positive G maneuvers. What is primarily meant by the term “non-aerobatic” is because the 200RV is not a counterweighted (pressure to decrease pitch) prop like most dedicated aerobatic props are. The 200RV is commonly used in aerobatic flight and structurally it will do fine – no worries.


So this was a BIG relief!

My second -7 is slowly getting ready for first start and when it's finally flying and done with Phase 1, it'll be interesting to compare my two -7's: they are about 95% identical and one of the diff''s are the prop's:
"Wilco" has a two blade MT prop and "Kermit" has a the WW 200RV prop.

So; it's exciting times ahead....


Don S; if you see this; I tried to answer your PM but your PM box is full....