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I've flipped back and forth now several times on this question. FP or CS Prop? Currently, I'm leaning towards the FP.

From what I understand the only downside to the FP is reduced climb rate (but still very acceptable) and possibily a harder time slowing it down.

I thought I would ask some pilots who have a FP for their input.

Do you like it?
Do you have any trouble slowing down?
I'm only 150 lbs and a lot of my flights will probably be alone. Any CG issues with the 7 if I don't have the extra weight on the front end with the CS?

Thanks,
Vince
N701VB

Vince, the best resource is Dan's W&B page from www.rvproject.com where you can see the weights of many different planes and their balance information.

Personally, if I weren't going CS I would put a Sensi on the nose.

I wouldn't say that the FP is any less of a performer. From what I have gathered, you need to pick a performance parameter. Either a cruise prop or a climb prop. Given the way the RV's climb, I would go with a cruise prop.

I have flown FP RV's and slowing down just requires some forward thinking. Plan ahead and you are fine.

Basically what it comes down to is, what do you want? I wanted a CS so I am getting one.

My two...

CJ

I have a fixed pitch propeller on my RV -6. I live in the Pacific Northwest. There have been times that I've wished for a C/S Prop at high elevation strips on hot days, but other that that I don't really need one. At KEUG, I've climbed out of the Delta Airspace while still parallel to the runway on a downwind departure.
As far as slowing the plane down goes, it does take some planning ahead. I have found that if I load it up a little in a steep turn, it slows quickly.
My airplane has an 0-320 turning a Catto 68-74 Propeller. The propeller weighs 15 lbs. I like the airplane's handling qualities as it is, but have had it loaded to the point of neutral stability in pitch. I still have the old 18 lb Prestolite Starter installed for weight and balance reasons.

A friend has an RV-6 with an 0-320 and a C/S prop. Needless to say, he out climbs me badly. At cruise at 8000' he is perhaps 2 Kts faster than I am. Starting out together, after 100 miles I could still see him. I use more fuel than he does.

Bob Severns
RV-6

I fly a 6 with a io 360 180 hp & prince fp prop. For me this is a great setup.
I get a solo roc of 2350' @2350 rpm 110 mph with 1/2 fuel. Level flight
210 mph. Slowing down is not bad just plan ahead!

I have a Catto prop on my RV-4. It's my understanding that if you put a wood fixed pitch prop on an RV-7 you will have similar CG issues as an RV-4 which tends to be a little tail heavy. Not bad, you just have to be mindful of the CG. I have added a harmonic dampener to my prop and it helped with the CG. You could probably do the same on the 7 with similar results. This may be what I end up doing too. If you put a Sensi metal FP prop on, you may not experience the CG issues but you will have the RPM limitation. It's all a trade off, you just have to decide what you want, more RPM, or more rear cargo capacity.

For my 7 I'm heavily leaning toward the Catto 3 blade prop with the Landoll harmonic balancer bolted to the ring gear to add some weight up front and some inertia to the prop.

You have to look at your flying - if you will be doing a bit of hot and high at small fields, then a C/S makes more sense. If T/O and climb performance are not a big issue, you will still be ahead of the spam can pack with the FP. My top priorities are cruise performance and fuel efficiency in cruise.
I am still in the debate myself, but leaning on a Catto 3 blade. Pretty on the -9A, and pitched for cruise will make Van's performance numbers. This has been confirmed by flyers and is guaranteed by Craig Catto. I will lose T/O and climb performance, but usually fly into sizeable fields here in the flatlands, so no issue. You will save an average of $5000 over a C/S (about 35-40 tanks of avgas), and won't have a TBO plus associated costs down the road.
Regarding slowing down entering the pattern or descending, I don't see it as an issue. You will quickly become accustomed to your plane's performance. If you insist on blazing on in, there are various techniques that other's have written of to help slow you down.
My 2 cents... .

I know I mentioned I would go CS, but I might go FP to start to get things rolling a little faster because of $$$. I am looking hard at the Felix Bicamber three blade by Fred Felix. Craig's props are beautiful, but better get your order in early...Carl, Terry W. called him today, and couldn't tell him when it would be shipped (didn't know), and it's supposed to be shipped the first part of January. I'm still looking at Catto, but orders need to be placed EARLY!

Vince,

I have a Sensenich prop on the front of my 7A. I am satisfied with the performance. Yes, a CS prop would give better acceleration and a better maximum climbrate but as others have said, the FP performance is so much better than a Cessna/Piper. The thing I like about the FP is the cost (it was the only prop I could afford) and the ease of maintenance. My prop annual is only taking off the spinner to inspect the prop bolts, pretty simple.

On a related note, a friend of mine has a 3 blade prop on a 7A. The problem he has is removing the lower cowl. It is difficult as you cannot get all the prop blades out of the way. Its not a show stopper but something to think about.

Good Luck!

Tom, bingo. I couldn't afford a fancy prop either. I had big plans for the 7, but financial reality is setting in for me. Probably will be back to the old two bladed Catto prop.

Another consideration - when ordering your Lyco or clone, it is possible to have the engine set up for C/S (hollow crank, etc), but have some minor mods done (plug in front shaft) by the builder/manufacturer so you use an FP. If down the road you change your mind and want to go C/S, it will be easy to pull the crank plug and convert over. Mattituck said they do this mod for a couple hundred dollars. It may help the resale value too knowing that a potential buyer could easily convert to C/S. If I do FP, I will definitely go this route when it's time for the engine order. This will be important to ensure performance is on par with the local builders after seeing what they decide - gotta to keep up with the Jensens...I mean Jones's .

Good point, Carl. I forgot to mention that I did get a hollow crankshaft and the other things necessary for a CS prop in the future.

In my opinion, there should be at least one flight situation where a FP prop should out perform a CS prop. Where this is depends on the FP prop. A "cruise" prop, for example, should have the same profile as a CS prop in cruise flight. Since the CS prop used oil pressure generated by the power of the engine to rotate its blades, a smaller amount of power is available for spinning the prop, therefore you would be slower. There are so many other things that affect speed that it is probably unnoticable but it makes sense to me.

Good Luck!