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Heavy props and RV-6 flying qualities

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whifof100ll

Well Known Member
Interested in opinions from RV-6 flyers on flying qualities of their RV-6's given different weight props.

I am getting ready to order FF forward for my 6 and will go with 180HP parallel valve Lyclone. Now that it is almost time to order, I'm waffling a bit on the prop selection.

I plan on gentlemens acro (loops rolls ect), and want good climb performance. I also plan on lots of cross country so speed and efficiency is important.

I am willing to spend more for the performace of a C/S prop, but not willing to compromise handling.

Based on what I've read and been told, Hartzell BA would be my choice for C/S. I've also been warned away from lighter C/S props by some that currently own them, wishing they had gone Hartzell. What worries me about the Hartzell is the weight and if it materially detracts from the flying qualities of the 6.

My other stong contender is a Catto (if I can get one). Not sure about 2 or 3 blades, but the attraction there is that I would not suffer in cruise, would have a better handling airplane, and in the case of a lost engine, would have more glide range. My assumption is that a light prop works well on a 6. True?

I am also interested in hearing about performance differences in 2 vs. 3 blade Catto props.

I had read some interesting posts about the Felix / Eclippse options and some other post about ground adjsutable props that might also be of interest, but I have not found an offereing yet.

I'm not really interested in the Sensi since it is heavy. If I'm going heavy, I'm going C/S.

Advice by 6 flyers that have upgraded to Hartzell C/S, was it worth it? Other considerations?

Regards,
Dale
 
whifof100ll said:
Interested in opinions from RV-6 flyers on flying qualities of their RV-6's given different weight props...
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I've flown quite a few combinations. All handled very well. A wood prop with O-320 has notably lighter elevator forces but that doesn't mean that more forward CGs don't fly very nicely indeed. Somewhere toward the midpoint would be my preference but one easily adapts to those small differences.
 
My RV6 was built with an O-360 and a Sensenich wood prop and flew that way for 1400hrs. The last 800 hrs it has flown with a Hartzell.

With the wood prop it was a lot lighter in pitch and a tad more fun to toss around. The down side was less pitch stability and the thing was a bear to land with lots of baggage and low fuel. The elevator got downright "goosey" in the flare. The Hartzell has made the handling much more stable. The plane can be trimmed for level flight and stays there for a long time. A heavy baggage load is no longer a problem. Overall I much prefer the additional weight up front since we used the plane a lot for travelling.

Martin Sutter
RV6 & RV7A
building an flying RV's since 1988
 
Acro weight.

Anothing motivating factor is acro weight.

If Vans suggest 1375# for acro, it doesn't take much to blow that in a 6.

For single person acro, I expect that I'd be fine with a Hartzell, but for 2 person acro it is probably a no go.

With a Catto, I could probably build a 1030 # plane painted and take along a skinney person and 10 gallons for a roll or two.

How hard do you guys feel the 1375# limit is?

Cheers
 
I have a 180/hartz and roll my 6 everytime out. Full fuel and two heavies (ie 1800lbs) or 1/4 fuel and no passenger. The plane doesn't care how much weight is in it as I'm only pulling about 1.5 g's.
 
....We have over 300 hours..

......with our three-bladed Catto and I'd do it exactly the same again. Craig pitched it for max cruise, per my request, and he delivered 4 MPH over Van's cruise numbers and the airplane came in at 1047 lbs, unpainted. I can tell you sincerely, that it is an absolute joy to fly, easy to land with full baggage and two up. I weigh 190 and my wife 130 and a 200 MPH cruise is normal.
We give up a little on takeoff distance (still under 750 feet) and climb performance. At 140 MPH she'll do 1600 FPM with two aboard...not too shabby.

Regards,
 
Nosewheel impact?

pierre smith said:
......with our three-bladed Catto and I'd do it exactly the same again. Craig pitched it for max cruise, per my request, and he delivered 4 MPH over Van's cruise numbers and the airplane came in at 1047 lbs, unpainted. I can tell you sincerely, that it is an absolute joy to fly, easy to land with full baggage and two up. I weigh 190 and my wife 130 and a 200 MPH cruise is normal.
We give up a little on takeoff distance (still under 750 feet) and climb performance. At 140 MPH she'll do 1600 FPM with two aboard...not too shabby.

Regards,
Click to expand...

Thanks Pierre,

I wonder how much the nosewheel tames the CG issues mentioned by others. I will have a tailwheel, but I have thin skins in the emp and no lights back there. I will also mount an Oddesey battery on the firewall ala RV-7. I think the fuel injected O360 will add a little weight up front as well.

If I do go light prop option, was thinking about a dynamic balancer as well which might help.

Either way, I would want to cowl it as if it was C/S to maintain that option.

Do you know if the Catto be cowled for C/S and used with a dynamic balancer?

Regards,
 
Doug Eves said:
I have a 180/hartz and roll my 6 everytime out. Full fuel and two heavies (ie 1800lbs) or 1/4 fuel and no passenger. The plane doesn't care how much weight is in it as I'm only pulling about 1.5 g's.
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I have a 135/Catto and roll my 9 everytime out when the wife isn't with me. Full fuel and two heavies (ie 1650lbs) or 1/4 fuel and no passenger. The plane doesn't care how much weight is in it as I'm only pulling about 1.5 g's. :)

Oh, that's right, I have a -9 and it isn't supposed be rolled. I'll just have to remember that next time out. ;)
 
I had a RV6 with an 0-360 and a Sensenich prop and it was a joy to fly. Light or heavy landings were fine. The climb performance was very good at 1650fpm at gross and in excess of 2000fpm light. Cruise was very good also. Save your money and go fixed pitch. Loops and rolls were a joy. The slight advantage of climb performance with a constant speed in my humble opinion isn't worth the cost or weight.
 
Sorry Norman, there is a huge difference....

Norman CYYJ said:
I had a RV6 with an 0-360 and a Sensenich prop and it was a joy to fly. Light or heavy landings were fine. The climb performance was very good at 1650fpm at gross and in excess of 2000fpm light. Cruise was very good also. Save your money and go fixed pitch. Loops and rolls were a joy. The slight advantage of climb performance with a constant speed in my humble opinion isn't worth the cost or weight.
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I have flown both, and there is no doubt the Hartzell Blended Airfoil CS significantly outclimes the fixed pitch machines I have flown. It also significantly improves short field landings and take off distances. If you have a fixed pitch that climbs well, it will suffer in cruise, so there is a balance and trade off. There is a reason CS props where developed.
However, that does not mean it outperforms a fixed pitch. Performance can be judged in many ways, that is why my 3 will be light with a fixed pitch, but for an entirely different mission than the 6.
My 6 with the firewall mounted battery and CS prop is slightly nose heavy when solo and just perfect loaded. I have the .016 tail surfaces.
 
Norman CYYJ said:
I had a RV6 with an 0-360 and a Sensenich prop and it was a joy to fly. Light or heavy landings were fine. The climb performance was very good at 1650fpm at gross and in excess of 2000fpm light. Cruise was very good also. Save your money and go fixed pitch. Loops and rolls were a joy. The slight advantage of climb performance with a constant speed in my humble opinion isn't worth the cost or weight.
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This question came up at our local RV builders meeting last weekend. A builder was getting opinions on the subject.

At our altitude of 4000'+, it was overwhelming in favor of C/S from all the guys that actually have them.

Since I've flown both, considering these higher elevation airport altitudes; the C/S was one of the most important items on the shopping list.

But.............then we have a lot of mountains, all around here, that suddenly shoot up thousands of feet! :D

L.Adamson
 
JonJay said:
I have flown both, and there is no doubt the Hartzell Blended Airfoil CS significantly outclimes the fixed pitch machines I have flown. It also significantly improves short field landings and take off distances. If you have a fixed pitch that climbs well, it will suffer in cruise, so there is a balance and trade off. There is a reason CS props where developed.
However, that does not mean it outperforms a fixed pitch. Performance can be judged in many ways, that is why my 3 will be light with a fixed pitch, but for an entirely different mission than the 6.
My 6 with the firewall mounted battery and CS prop is slightly nose heavy when solo and just perfect loaded. I have the .016 tail surfaces.
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There is a difference I won't argue. I have also many hours on both. As for stopping shorter maybe but I would never have know unless you have a reversing prop. Slowing down is a bit faster and descent rate can be faster at the start. Take off is for sure better but by only by maybe 200 ft. But if you are operating out of 1000 foot strip it might make a bit of a difference. Cruise is the same. But the cool factor of having a constant speed prop to impress other pilots and friends has no price tag. To me not worth the extra weight or money or maintenance.
 
RV-6 taildragger W&B

Can some of you guys post your empty weight and empty CG for your tailwheel RV-6's.

I particularly interested in comparing W&B information between O360 parallel valve powered RV-6 (taildragger) equipped composite or wood FP props and Hartzell C/S. If you post the weight of a composite or wood prop, can you please tell me the prop weight and additional weight you have added to get the CG where you want it?

Regards,
Dale
 
RV-6 N168TX

Day/Night VFR. Dynon D10A w/backups, dual comms and dual GPS.
Catto 3-blade...wt=17 lbs.
Aircraft empty weight=1026 lbs.
No added ballast. Fully loaded it is close to aft limit. My airplane is a little more pitch sensitive than most, but you get used to that. It's been flying since 5/93 and I wouldn't change a thing.
BTW, the 1375 lb. gross weight for acro is FIRM. It's based on G-loading.
 
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CS Prop now and later

Save time and energy. Put a CS prop on it from the outset. Make sure you have a CS prop compatible engine, whether building or buying a flying RV. Besides performance on t/o and climb, you will not have to manage rpm with the throttle, never good. I added about 20-25 lbs to my 1st RV6 by putting a CS prop on it, vs a metal Sensenich, AND got the empty weight CG more forward, always good. There are lots more reasons for a CS prop, and the debate is endless of course. My 2 cents from experience.
 
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