RivetBangers.com

I sent my order in to Fred Felix this week to have my prop made. It will be his "BiCambered" airfoil prop, two blade, fixed pitch wood prop for 160hp.

His design spec for his prop on a 160hp 7 is...

The design point for your RV is for 2,850 RPM at 200 MPH when flying at sea level. This is to allow redline RPM of 2,700 at 8,500' MSL which would be 75% power. This should give 190 - 192 MPH TAS.

My goal for 160hp is 190mph max cruise, and 180mph at 65%. With the BiCambered prop, this should be doable.



http://bicambertechnology.com/application1.htm

The three blade prop is really cool looking, but anything below 200hp won't turn it fast enough to get the performance it is supposed to deliver. People use it, but only for looks. They are much slower, according to Fred.



So, two blade it is!

Wacky! I've never even heard of them. Congrats on a new toy ordered!

Guy

Never heard of Felix wood props??? The BiCambered Tech stuff is new, but Felix has been making props for a long time. He's working with Paul Lipps on the new Elippse prop...Paul designed it, Fred built the one for his RV-6 (Catto built the one on Paul's Lancair).



[Edited for more info]

Chad-

Congrats on your purchase. I ordered my prop today also -- Whirlwind 200RV!

bullojm1 wrote:<snip>I ordered my prop today also -- Whirlwind 200RV!

Sweet dude!! If I had your money, I'd burn mine!!

Seriously...that WW 200RV is one sweet prop! Jack has it on his 7, and it performs as advertised! Cool!!

man, there should be a whole bunch of us taking to the skys at one time here shortly..

cjensen wrote:

bullojm1 wrote:<snip>I ordered my prop today also -- Whirlwind 200RV!

Sweet dude!! If I had your money, I'd burn mine!!

Hey! That's my line!!!

Chad, I never even heard of them either!

Leave it to you to find the no name guys!



OTOH, I like the looks of them. I will keep my finger on the pulse of this one, for sure!

CJ

Chad, what were your deciding factors for this prop? What others did you consider, etc.?

1:1_Scale wrote:Chad, what were your deciding factors for this prop? What others did you consider, etc.?

"The list is long, but distinquished!"

I've been talking to Fred for about 7 months about his props (first contact was July 18, '07). He has answered EVERY single question in a timely manner, and has been completely honest in his responses. He sent me a sheet with customer testimonials. I read thru every page on the BiCambered website about how it works to generate more thrust with a quieter sound signature. Fred has been in the prop business for a long, long time, and has been doing custom work for special applications for a long, long time.

Once the decision to go with a fixed pitch prop was made, reading about Felix props, and talking to the man himself made the decision pretty easy.

Another factor...Catto props are the norm for non-metal fixed pitch props for RV's, I think we'd all agree. HOWEVER...I know the man is busy, but I can't understand how an email or two goes unanswered for two months with questions regarding specifics on a possible order. I know he has plenty of business, and won't miss me, but I stopped trying to get a response. People love his props, and swear by them. A friend of mine here in town did get an order in for his two blade prop for his O-360 7A. It was supposed to be here in January...he still doesn't have it. Another friend waited 13 months PAST his projected delivery date for his. He has it now, but 13 months?

Cost...The Felix two blade prop will perform as good or better (with the BiCambered airfoil) as the Catto two blade for about $500 less. Even the three blade is $300 less, and that's WITH the BiCambered charge of $230 ($140 for the two blade). This prop cost me $1189 with BiCamber, and special paint.

I don't know how many Felix props are flying, but I'd be willing to bet there are more than Prince and Performance, and probably on par with Catto. NOT on RV's, but there are other airplanes out there...

I considered everything...Catto, Performance, Prince, Hammond, MT, Sensenich (metal and wood), IVO, McCauley, Wernke, Sterba...It comes down to what you get for the money, and I firmly believe that this BiCambered Felix prop is THE bang for the buck in props.

I ruled out a constant speed prop a while back because of cost of purchase, and maintenance/overhaul. The benefits of the CS prop, in my opinion only, do not outweigh the cost of entry.

What about an Elippse prop? I'm sure there aren't many out there, just curious if it crossed your mind?

Yeah, I made note of that prop in an earlier post in this thread...

They are really cool, and Fred Felix is the one building them now...Catto did build one that is on Pual's Lancair.

Being that it's a brand new prop, and only a couple flying, with Paul flying the airplane, I'm not gonna be a beta tester on it. I did ask Fred about the Elippse, and he is excited about it, but Paul is flying the numbers off the one on his -6 right now to see if any changes need to be made. It's gonna be expensive though...I don't have my Contact! magazine in front of me, but I seem to remember $3500 for it. I'll look it up tonight (if I can remember to), and quote the price that's in the magazine.

http://www.batterson.net/EAA499/Issue77_8-13.pdf

I just received an email from Fred that my prop will be number 410, and he started building props in 1993.

captain_john wrote:Chad, I never even heard of them either!

Leave it to you to find the no name guys!

CJ

I hardly think Felix props are "no name" props. You guys need to do more research!

cjensen wrote:

captain_john wrote:Chad, I never even heard of them either!

Leave it to you to find the no name guys!

CJ

I hardly think Felix props are "no name" props. You guys need to do more research!

Research schmesearch!

Don't confuse me with any facts!

CJ

cjensen wrote:They are really cool, and Fred Felix is the one building them now...Catto did build one that is on Pual's Lancair.
http://www.batterson.net/EAA499/Issue77_8-13.pdf

Yeah, I've read that article, and it makes a lot of sense to me. Actually, it makes more sense to me than an airfoil with a ditch cut in the middle of it I find the Bicamber stuff quite interesting, and have read a fair amount of stuff on that page when you first posted it a while back. Does Felix have any direct numbers comparison between his standard prop and a bicambered prop?

1:1_Scale wrote:Does Felix have any direct numbers comparison between his standard prop and a bicambered prop?

I'm sure he does, but I don't have anything. All I know is that the BiCambered prop is creating more thrust in all realms, so in theory, it should be faster than the standard Felix airfoil.

I'll email him and ask if he has direct comparisons between standard and BiCambered...

Looks like some guy did a software simulation of drag with this design and it didn't end up doing well compared to the other designs. Does Felix talk about this at all? You can make more lift all you want, but if you have more drag to overcome, you have essentially done nothing.

http://www.rcgroups.com/forums/showthread.php?t=611943

Very true, but the design is drag reducing as well. It is talked about on the BCT site...

http://www.bicambertechnology.com/technology.htm

It's shown in this drawing how drag from airflow is reduced...now, it's just a drawing, but from the reviews I have read, from Felix's customers, it works in practice as well...



I can forward the documents to anyone who would like them, but without his permission to post on the internet, I'm not gonna put them here...

cjensen wrote:I'll email him and ask if he has direct comparisons between standard and BiCambered...

Cool I would think as a propeller manufacturer, it would be pretty easy for him to test the two designs back to back, esp. with a fixed pitch prop

There was a fairly detailed write up about Felix propellers in Sport Aviation about 10 or 15 years ago. I was quite interested in them myself at the time. I believe Van had something in RVator many years ago also and he was not real impressed with them as I recall. Felix props were advertised in Sport Aviation for several years and the write up in SA. Then they were listed again until about a year ago. I have been looking for on a RV at Oshkosh but never saw one. Of course I didn't make it to Oshkosh last year for the first time since 1990. Maybe there will be some there this year. Chad I will be interested in your feedback when you get your RV flying.