---------------------------------------------------------- RV-List Digest Archive --- Total Messages Posted Thu 12/29/05: 21 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:18 AM - Re: rpm run up vs tail wheel staying down (luckymacy@comcast.net (lucky)) 2. 08:40 AM - MT Props in IMC (Dan Beadle) 3. 08:52 AM - Re: Lyco rumble (Brad Gould) 4. 10:00 AM - Re: Darn good Christmas! (Chopper 1) 5. 10:22 AM - Re: MT Props in IMC (David Leonard) 6. 12:19 PM - Re: Lyco rumble (Rob Prior (rv7)) 7. 01:03 PM - Re: Lyco rumble (Bob J) 8. 01:48 PM - Re: MT Props in IMC (Kyle Boatright) 9. 03:54 PM - Re: Darn good Christmas! (Bobby Hester) 10. 04:21 PM - Flap Fairing Fit (Mike Draper) 11. 06:26 PM - Re: Darn good Christmas! (Fiveonepw@aol.com) 12. 06:41 PM - Re: Darn good Christmas! (Fiveonepw@AOL.COM) 13. 06:49 PM - Re: rpm run up vs tail wheel staying down (Fiveonepw@aol.com) 14. 07:19 PM - TruTrak DigiFlight II VSGV (Russell Daves) 15. 07:45 PM - Re: rpm run up vs tail wheel staying down (dick martin) 16. 08:10 PM - Re: MT Props in IMC (dick martin) 17. 08:51 PM - Re: rpm run up vs tail wheel staying down (JOHN STARN) 18. 10:37 PM - Re: MT Props in IMC (LessDragProd@aol.com) 19. 11:33 PM - Re: MT Props in IMC (LessDragProd@aol.com) 20. 11:56 PM - Re: AoA (Todd Bartrim) 21. 11:56 PM - Re: AOA sensor mounting question (Todd Bartrim) ________________________________ Message 1 _____________________________________ Time: 05:18:53 AM PST US From: luckymacy@comcast.net (lucky) Subject: Re: RV-List: rpm run up vs tail wheel staying down --> RV-List message posted by: luckymacy@comcast.net (lucky) stick was full back. my rpm gauge read ~1700 rpm. later i determined that i'm reading lower than actual. A standbyer with hand held tach recorded ~2200 rpm. -------------- Original message -------------- From: "Randy Lervold" > --> RV-List message posted by: "Randy Lervold" > > ----- Original Message ----- > From: "lucky" > To: "RV-List" ; "RV yahoo" > ; "RV8 List" > Subject: RV-List: rpm run up vs tail wheel staying down > > > > --> RV-List message posted by: luckymacy@comcast.net (lucky) > > > > When running up to about 2200 rpm, my RV8 tail lifts off of the ground. I > > have an angle valved, 200 hp engine with hartzell CS prop. 27 degrees up > > elevator throw. > > > > Does that sound right? > > > > I haven't done my CG yet but I have my battery in the back and the elt > > installed under the VS. My tail is relatively heavy compared to another > > local tail dragger 8 I have picked up. He has a 180 HP engine and also a > > CS prop, battery on the FW and thinks something is wrong as his won't lift > > up at that rpm. > > > > thoughts? > > > > lucky > > Lucky, > If you're not holding your stick full back then the tail may well come up, I > was never brave enough to try it. I did do quite a few 2400 rpm runs though > for prop balancing, but again with the stick full back and had no problem. > > Randy Lervold > www.rv-3.com > www.rv-8.com > > > > > > > > > > > > > > stick was full back. my rpm gauge read ~1700 rpm. later i determined that i'm reading lower than actual. A standbyer with hand held tach recorded ~2200 rpm. -------------- Original message -------------- From: "Randy Lervold" randy@romeolima.com -- RV-List message posted by: "Randy Lervold" ----- Original Message ----- From: "lucky" To: "RV-List" ; "RV yahoo" ; "RV8 List" Subject: RV-List: rpm run up vs tail wheel staying down -- RV-List message posted by: luckymacy@comcast.net (lucky) When running up to about 2200 rpm, my RV8 tail lifts off of the ground. I have an angle valved, 200 hp engine with hartzell CS prop. 27 degrees up elevator throw. Does that sound right? I haven't done my CG yet but I h ave my battery in the back and the elt installed under the VS. My tail is relatively heavy compared to another local tail dragger 8 I have picked up. He has a 180 HP engine and also a CS prop, battery on the FW and thinks something is wrong as his won't lift up at that rpm. thoughts? lucky Lucky, If you're not holding your stick full back then the tail may well come up, I was never brave enough to try it. I did do quite a few 2400 rpm runs though for prop balancing, but again with the stick full back and had no problem. Randy Lervold www.rv-3.com www.rv-8.com e ________________________________ Message 2 _____________________________________ Time: 08:40:58 AM PST US Subject: RV-List: MT Props in IMC From: "Dan Beadle" --> RV-List message posted by: "Dan Beadle" I have heard that wooden props are not very durable in rain and ice. The MT props seem to address some of the issue with composite and SS inserts. Does anyone have experience with a high-time MT prop's performance? I like the 20# weight savings up front, but am concerned about wear. While my RV will be mostly aerobatics in clear air, we are setting it up for IFR and intend to fly it if the weather is appropriate ________________________________ Message 3 _____________________________________ Time: 08:52:46 AM PST US From: Brad Gould Subject: Re: RV-List: Lyco rumble --> RV-List message posted by: Brad Gould If the piston speed is the same b/w the Subbie and the Lycoming, but the RPM is higher, the piston acceleration should be higher. The average acceleration intuitively would be proportional to the rotational speed. Is this right? I would imagine that piston acceleration has a greater effect on engine longevity than piston speed, since the acceleration would determine the stresses imposed on the engine components, while speed itself seems to be more relevant to internal friction, which can be lubricated away. Brad Not yet started on an 8 Time: 10:35:25 PM PST US From: Tedd McHenry Subject: Re: Lyco rumble & Subie was :Re: Subaru 6900 RPM in a RV Thank goodness I kept my spreadsheet! Piston Speed ============ Piston speed is simply one half the stroke times the rotational speed (in appropriate units). Another way of looking at this is the ratio of stroke lengths for two different engines gives the ratio of piston speeds at a given RPM. The stroke for a Lycoming O-360 is 4.375 inches. The stroke for an Eggenfellner Subaru is 3.11 inches. (Gary, you were right not to trust my memory. I had remembered the Subaru stroke as being closer to 2.5 inches.) Therefore, the stroke ratio for the two engines is 4.375/3.11=1.4. So the Subaru has the same piston speed at 3400 RPM as the Lycoming has at 2400 -- lower than I remembered. Eggenfellner recommends a cruise RPM between 3800 and 4200, which is between 12 and 24 percent higher than the Lycoming's cruise piston speed (assuming the Lycoming is cruising at 2400 RPM). --------------------------------- ________________________________ Message 4 _____________________________________ Time: 10:00:35 AM PST US From: "Chopper 1" Subject: Re: RV-List: Darn good Christmas! --> RV-List message posted by: "Chopper 1" Sounds great!! Bring it to the meeting and show it ???? Mike ----- Original Message ----- From: Subject: RV-List: Darn good Christmas! > --> RV-List message posted by: Fiveonepw@aol.com > > Best present I got this year (next to my new front tire) was the one-six > right DVD- If y'all haven't seen this, it's the best documentary I've seen (even > if there were no RVs in it) since Michelle's "The West Coast RV Trip"- The > air2air fotogs are well worth the price of admision alone... > > Get it from Sporty's http://onesixright.com > > Mark do not archive > > ________________________________ Message 5 _____________________________________ Time: 10:22:48 AM PST US From: David Leonard Subject: Re: RV-List: MT Props in IMC --> RV-List message posted by: David Leonard I think that is mostly an issue with unprotected props. I would get the leading edge protection and you should be OK. I have flown my aymar DeMuth wood prop with composite leading edge protection into moderate rain on several occasions, totaling about an hour of flight in rain. There is no evidence of any problem or damage. Ice would probably be a different story. Dave Leonard On 12/29/05, Dan Beadle wrote: > > --> RV-List message posted by: "Dan Beadle" < > Dan.Beadle@hq.InclineSoftworks.com> > > I have heard that wooden props are not very durable in rain and ice. > The MT props seem to address some of the issue with composite and SS > inserts. Does anyone have experience with a high-time MT prop's > performance? I like the 20# weight savings up front, but am concerned > about wear. While my RV will be mostly aerobatics in clear air, we are > setting it up for IFR and intend to fly it if the weather is appropriate > > -- Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html ________________________________ Message 6 _____________________________________ Time: 12:19:57 PM PST US From: "Rob Prior (rv7)" Subject: Re: RV-List: Lyco rumble --> RV-List message posted by: "Rob Prior (rv7)" On 8:52:15 2005-12-29 Brad Gould wrote: > If the piston speed is the same b/w the Subbie and the Lycoming, but > the RPM is higher, the piston acceleration should be higher. The > average acceleration intuitively would be proportional to the > rotational speed. Is this right? I would have to work through the entire calculation of the engine dynamics to be sure that's right, but it sounds correct. However, I believe the parts in the Subaru engine are also smaller, so the mass of the moving parts is lower than in the Lycoming. > I would imagine that piston > acceleration has a greater effect on engine longevity than piston > speed, since the acceleration would determine the stresses imposed on > the engine components, while speed itself seems to be more relevant to > internal friction, which can be lubricated away. You're partly right. Acceleration is a factor, but it's only part of the story. The real factor to consider is the forces on the components. Since Force = Mass x Acceleration, the force is proportional to both the mass of the components *and* the acceleration. In this case, the acceleration is a higher, but the mass is lower. It's possible the net force could be higher, lower, or the same, but I don't have the numbers to say which is the case. -Rob ________________________________ Message 7 _____________________________________ Time: 01:03:13 PM PST US From: Bob J Subject: Re: RV-List: Lyco rumble --> RV-List message posted by: Bob J Piston speed is just one aspect of sizing the internal components of an engine to and making sure all the parts are up to task (rod journal diameter, mains diameters, etc.) Speaking strictly about piston speeds, you have to run the calculations based on things like the height of the crankshaft circle, lateral position on the crankshaft circle, piston pin height, height of the connecting rod triangle, etc. In plain english this means as the crank is turning the piston speed is constantly changing, so you calculate your piston speeds based on the position of the crank (theta), and the length of the connecting rod. In other words, you can run higher rpm's on an engine, but the piston speeds can be similar to a slower-turning engine with a larger diameter crank and a longer connecting rod. Obviously there are many more considerations one could get into comparing Subaru vs. Lyc. but to just use rpm's as a factor in deciding one engine over another is short-sighted. Just because one engine runs 7000 rpm's at cruise in itself doesn't necessarily mean that forces exerted on internal components is that much more than of a slower-turning engine. Again piston speed is just one part of the whole. Regards, Bob Japundza RV-6 flying F1 under const. On 12/29/05, Rob Prior (rv7) wrote: > > --> RV-List message posted by: "Rob Prior (rv7)" > > On 8:52:15 2005-12-29 Brad Gould wrote: > > If the piston speed is the same b/w the Subbie and the Lycoming, but > > the RPM is higher, the piston acceleration should be higher. The > > average acceleration intuitively would be proportional to the > > rotational speed. Is this right? > > I would have to work through the entire calculation of the engine dynamics > to be sure that's right, but it sounds correct. However, I believe the > parts in the Subaru engine are also smaller, so the mass of the moving > parts is lower than in the Lycoming. > > > I would imagine that piston > > acceleration has a greater effect on engine longevity than piston > > speed, since the acceleration would determine the stresses imposed on > > the engine components, while speed itself seems to be more relevant to > > internal friction, which can be lubricated away. > > You're partly right. Acceleration is a factor, but it's only part of the > story. The real factor to consider is the forces on the > components. Since > Force Mass x Acceleration, the force is proportional to both the mass of > the components *and* the acceleration. In this case, the acceleration is > a > higher, but the mass is lower. It's possible the net force could be > higher, lower, or the same, but I don't have the numbers to say which is > the case. > > -Rob > > ________________________________ Message 8 _____________________________________ Time: 01:48:17 PM PST US From: "Kyle Boatright" Subject: Re: RV-List: MT Props in IMC --> RV-List message posted by: "Kyle Boatright" My experience with an Aymar/Demuth prop in the rain is different. On the way to SnF last year, I flew through areas of light rain or drizzle for 45 minutes at 2100 rpm or less. The rain was intermittant, so the exposure to rain was under 30 minutes. On arrival at Lakeland, I found that the paint was off the first 6" of the leading edge and there was minor damage on the composite leading edge. A little sandpaper and some rattle can paint took care of the damage when I got home from the show. Kyle Boatright 0-320 RV-6 N46KB ----- Original Message ----- From: "David Leonard" Subject: Re: RV-List: MT Props in IMC > --> RV-List message posted by: David Leonard > > I think that is mostly an issue with unprotected props. I would get the > leading edge protection and you should be OK. > > I have flown my aymar DeMuth wood prop with composite leading edge > protection into moderate rain on several occasions, totaling about an hour > of flight in rain. There is no evidence of any problem or damage. Ice > would probably be a different story. > > Dave Leonard ________________________________ Message 9 _____________________________________ Time: 03:54:28 PM PST US From: Bobby Hester Subject: Re: RV-List: Darn good Christmas! --> RV-List message posted by: Bobby Hester I got my copy for Christmas :-) Here is something I read last week that makes me sick, especially after the release of this movie. I can't beleive they are even allowed to do this. They have banned the very aircraft that aviation is showing the largest growth in right now. HOW SOCAL IS WORKING TO BAN DIVERSITY EAA says it's making progress in reversing or modifying restrictions on experimental aircraft imposed on four busy California airports by the Van Nuys Flight Standards District Office (FSDO). In April of 2004, then-FSDO Manager Robyn Miller issued a memo that effectively barred some experimental aircraft from regular operations at Van Nuys (yes, of One Six Right fame ), Whiteman, Burbank and Santa Barbara airports. Most experimentals are homebuilts but many warbirds are operated in the experimental category, also. The memo says that "phase II and 'normal' operations [by experimentals] will not be allowed" at the four airports although "exceptions may be made based upon current office policy, certification category, aircraft type and operator experience." More... Surfing the Web from Hopkinsville, KY Visit my web site at: http://www.geocities.com/hester-hoptown/RVSite/ RV7A Slowbuild wings-QB Fuse-XPO360 engine :-) Fiveonepw@aol.com wrote: >--> RV-List message posted by: Fiveonepw@aol.com > >Best present I got this year (next to my new front tire) was the one-six >right DVD- If y'all haven't seen this, it's the best documentary I've seen (even >if there were no RVs in it) since Michelle's "The West Coast RV Trip"- The >air2air fotogs are well worth the price of admision alone... > >Get it from Sporty's http://onesixright.com > >Mark do not archive > > > > > > > > > ________________________________ Message 10 ____________________________________ Time: 04:21:26 PM PST US From: Mike Draper Subject: RV-List: Flap Fairing Fit --> RV-List message posted by: Mike Draper I'm stumped and am curious if others ran into the same problem. I just finished my first trial fit of the wings. Sweep and incidence is spot on. After a gazillion interations of trim, remove, install and trim again my right flap fits nicely and tucks under the fuselage. My problem is trying to fit the *%$&&!@!! aft flap fairing (F- 872C). I can line up the topside with the flap, however, there is no way I can get the bottom side to fit under the fuselage. It's a gross misfit, not even close to the plans or the pictures on Randy's site. I figure I must be doing something wrong. What did everyone else experience? Do I need to take a pair snips to it? Thanks in advance for any tips, comments or moral support. Happy New Year. Mike Draper Finish ________________________________ Message 11 ____________________________________ Time: 06:26:25 PM PST US From: Fiveonepw@aol.com Subject: Re: RV-List: Darn good Christmas! --> RV-List message posted by: Fiveonepw@aol.com Woohoo- I get the "presentation" two months in a row! It really is an awesome video- you'll see... Mark DO NOT ARCHIVE ________________________________ Message 12 ____________________________________ Time: 06:41:31 PM PST US From: Fiveonepw@AOL.COM Subject: Re: RV-List: Darn good Christmas! --> RV-List message posted by: Fiveonepw@aol.com Yeah, we'll see how it shakes out- will be interesting to see how "involved" EAA gets with this one- pretty damn cool video, though! Ready to fly yet? May be going down to Ft Payne AL 4A9 for b'fast Sat- if not, ya gonna be out at yer hanger? ________________________________ Message 13 ____________________________________ Time: 06:49:42 PM PST US From: Fiveonepw@aol.com Subject: Re: RV-List: rpm run up vs tail wheel staying down --> RV-List message posted by: Fiveonepw@aol.com In a message dated 12/28/2005 11:41:49 PM Central Standard Time, jhstarn@verizon.net writes: Every RV is different BUT ALL of them can, have & will continue to nose over. >>> Thanks a lot, John- now my nosedragger ain't even an RV! (sniff) OH! I get it- yer talkin' about them "off field" landings! 8-) (never mind...) Mark RV-6"A" do not archive ________________________________ Message 14 ____________________________________ Time: 07:19:07 PM PST US From: "Russell Daves" Subject: RV-List: TruTrak DigiFlight II VSGV --> RV-List message posted by: "Russell Daves" For those of you who have the DigiFlight II VSG or the VSGV TruTrak advised me today that they now have the VSGV software completed to couple with the GRT EFIS. I will be sending in my VSGV for software upgrade (no cost since I purchased the VSGV model originally. VSG models can also be upgraded but at the price differently for the VSGV version. Russ Daves RV-10 #40044 ________________________________ Message 15 ____________________________________ Time: 07:45:13 PM PST US From: "dick martin" Subject: Re: RV-List: rpm run up vs tail wheel staying down --> RV-List message posted by: "dick martin" Randy, I had a 200 hp I0-360 w/Hartzell originally on my RV8.The 200hp engine is considerably heavier than the 180 (approx 30 lbs) and mine did the same thing even though a weight and balance indicaated a proper CG. Do your W&B to confirm an acceptable CG before you become overly concerned. Dick Martin RV8 N233M the fast one ----- Original Message ----- From: "Randy Lervold" Subject: Re: RV-List: rpm run up vs tail wheel staying down > --> RV-List message posted by: "Randy Lervold" > > ----- Original Message ----- > From: "lucky" > To: "RV-List" ; "RV yahoo" > ; "RV8 List" > Subject: RV-List: rpm run up vs tail wheel staying down > > >> --> RV-List message posted by: luckymacy@comcast.net (lucky) >> >> When running up to about 2200 rpm, my RV8 tail lifts off of the ground. >> I >> have an angle valved, 200 hp engine with hartzell CS prop. 27 degrees up >> elevator throw. >> >> Does that sound right? >> >> I haven't done my CG yet but I have my battery in the back and the elt >> installed under the VS. My tail is relatively heavy compared to another >> local tail dragger 8 I have picked up. He has a 180 HP engine and also >> a >> CS prop, battery on the FW and thinks something is wrong as his won't >> lift >> up at that rpm. >> >> thoughts? >> >> lucky > > Lucky, > If you're not holding your stick full back then the tail may well come up, > I > was never brave enough to try it. I did do quite a few 2400 rpm runs > though > for prop balancing, but again with the stick full back and had no problem. > > Randy Lervold > www.rv-3.com > www.rv-8.com > > > ________________________________ Message 16 ____________________________________ Time: 08:10:17 PM PST US From: "dick martin" Subject: Re: RV-List: MT Props in IMC --> RV-List message posted by: "dick martin" Dan The MT prop will not dissapate the electric charge of a lightning strike because of the construction design of the blades. The only composite propeller that will do it reliably is the Aero Composites carbon fibre prop. The ACI prop has a perforated metal shield molded into the blades full length. It also has a cast Nickle Cobalt one piece leading edge. In my testing , I have found tht the ACI prop will yield a considerably higher speed than either the MT or the Hartzell. Climb will be slightly less than the MT (100 to 300 fpm). It will be considerably smoother than the Hartzell and 10 to 15 lbs lighter depending on length. In my testing of different lengths on my RV8 a 74" is optimum. A RV7 or RV6 will probably better with a 72". Note: the hub and blade retention system on the ACI is considerably stronger than the MT (no lag screws) because it uses a screwless blade shank retention system and a forged one piece hub. If you want to discuss this in detail, (I have over 500 hours on my ACI prop) please call me at 920 619 6968. Dick Martin RV8 N233M the fast one ----- Original Message ----- From: "Dan Beadle" Subject: RV-List: MT Props in IMC > --> RV-List message posted by: "Dan Beadle" > > > I have heard that wooden props are not very durable in rain and ice. > The MT props seem to address some of the issue with composite and SS > inserts. Does anyone have experience with a high-time MT prop's > performance? I like the 20# weight savings up front, but am concerned > about wear. While my RV will be mostly aerobatics in clear air, we are > setting it up for IFR and intend to fly it if the weather is appropriate > > > ________________________________ Message 17 ____________________________________ Time: 08:51:43 PM PST US From: "JOHN STARN" Subject: Re: RV-List: rpm run up vs tail wheel staying down --> RV-List message posted by: "JOHN STARN" I was talking about tail wheel RV's, but now that you thought of it, I have heard of several "A" types having their spinners making contact with the ground. Not by over aggressive run-ups however. Not all of those were "off" field either. "A's" don't make good wheelbarrows if landed on that end (the "A" end) first. Dirty side UP, Yep, that's why N561FS has a tall, strong rollover bar (or as we refer to it: "the entrance & egress handle device", we don't wear "crash helmets" either ) . 8*) KABONG Do Not Archive ----- Original Message ----- From: Subject: Re: RV-List: rpm run up vs tail wheel staying down > --> RV-List message posted by: Fiveonepw@aol.com > > In a message dated 12/28/2005 11:41:49 PM Central Standard Time, > jhstarn@verizon.net writes: > Every RV is different BUT ALL of them > can, have & will continue to nose over. >>>> > > Thanks a lot, John- now my nosedragger ain't even an RV! > > (sniff) > > OH! I get it- yer talkin' about them "off field" landings! 8-) > (never mind...) > > Mark RV-6"A" > do not archive ________________________________ Message 18 ____________________________________ Time: 10:37:27 PM PST US From: LessDragProd@aol.com Subject: Re: RV-List: MT Props in IMC --> RV-List message posted by: LessDragProd@aol.com The MT propeller blades have a stainless steel leading edge insert. Stainless steel is three times more resistant to water and sand erosion than aluminum. Dull Gray blades with Gloss White tips is recommended for an IFR propeller. This works just the same as the gray painted aluminum blades. The rain and sand will wear off the Dull Gray top coat of the paint and expose the dull Gray primer coat underneath. Just the same as the aluminum blades; as the worn off Gray top coat exposes the Gray aluminum underneath. Unlike the aluminum blades, MT propeller blades are not life limited. The stainless steel leading edge can be replaced, if needed. And, in the case of blade tip damage, up to 15% of the blade length can be replaced. Specifically, the MT Propeller blades can be rebuilt back to their original length. You might consider a counterweighted blade MT Propeller for aerobatics. It has the obvious benefit of going to coarse pitch with a momentary loss of oil pressure and protecting the engine and propeller from overspeeding. There is also a 67% reduction in propeller drag in the event of a total oil pressure lose in the event of an engine failure. Unfortunately, the counterweights add 12 pounds to a 3 blade MT Propeller. Regards, Jim Ayers In a message dated 12/29/2005 8:41:52 AM Pacific Standard Time, Dan.Beadle@hq.InclineSoftworks.com writes: --> RV-List message posted by: "Dan Beadle" I have heard that wooden props are not very durable in rain and ice. The MT props seem to address some of the issue with composite and SS inserts. Does anyone have experience with a high-time MT prop's performance? I like the 20# weight savings up front, but am concerned about wear. While my RV will be mostly aerobatics in clear air, we are setting it up for IFR and intend to fly it if the weather is appropriate ________________________________ Message 19 ____________________________________ Time: 11:33:34 PM PST US From: LessDragProd@aol.com Subject: Re: RV-List: MT Props in IMC --> RV-List message posted by: LessDragProd@aol.com Hi Dick, Are you smoking the funny stuff? :-) You're talking about a certified propeller manufacturer who has had the lightning strike test performed. Perhaps you should be comparing the ACI prop to other uncertified propeller manufacturers; like Whirlwind, or Ivoprop. Jim Ayers Less Drag Products, Inc. - An MT Propeller distributor In a message dated 12/29/2005 8:11:30 PM Pacific Standard Time, martin@gbonline.com writes: --> RV-List message posted by: "dick martin" Dan The MT prop will not dissapate the electric charge of a lightning strike because of the construction design of the blades. The only composite propeller that will do it reliably is the Aero Composites carbon fibre prop. The ACI prop has a perforated metal shield molded into the blades full length. It also has a cast Nickle Cobalt one piece leading edge. (Stuff Cut) Dick Martin RV8 N233M the fast one ________________________________ Message 20 ____________________________________ Time: 11:56:13 PM PST US From: "Todd Bartrim" Subject: RE: RV-List: AoA --> RV-List message posted by: "Todd Bartrim" Hi Steve; I have both the PSS AOA and the D10 with AOA. I bought the PSS system early in my build and bought the D10 after first flight. The PSS system should be a better system due to it's direct measurement of AOA, while the D10 is an inferred measurement, however I have found them to track each other perfectly and both give accurate warning of a stall. The only time they don't track together is during a turn and this is expected as I have them mounted on opposite wings. The early D10 doesn't have any audio output, so the PSS system is nice to have for this feature and I also mounted my PSS LED display on the glaresheild which gives me a crude but effective poor man's HUD, which is visible in all but direct sunlight. If I was building today I would just go with the new Dynon or comparable EFIS that has this feature as it has proven (to me) to be as accurate as a stand alone system. Todd --> RV-List message posted by: "Steve Sampson" Has anyone experience of using both the AoA in the Dynon D10A and the dedicated systems (Advanced Flight Systems and Lift Reserve Co.). For the money you pay I would hope the later systems are providing a whole lot more info., but I wonder? My only data point is that I have flown with the non audio D10 system and it appeared to give a very repeatable forecast of the stall. Thanks, Steve. ________________________________ Message 21 ____________________________________ Time: 11:56:13 PM PST US From: "Todd Bartrim" Subject: RE: RV-List: AOA sensor mounting question --> RV-List message posted by: "Todd Bartrim" Unfortunately I have to keep my RV tied down outside 365 days a year which includes melting snow on the wings, which should be the worst condition for water entering the top AOA sensing hole and yet I have never found so much as a drop of water when checking the drain. YMMV Todd --> RV-List message posted by: "RV Builder (Michael Sausen)" Rob (AFS guy) had mentioned at OSH that he really never has any water in it. The hole is so small it is difficult to penetrate with water. I plan on leaving it without a drain hole until I can gauge if it's a problem or not. Michael Sausen -10 #352 Fuselage --> RV-List message posted by: RKAlex123@aol.com A question for those of you that have installed an Angle of Attack indicator. The upper wing sensor has a water separator which requires access from below to drain any accumulated water. Did you just drill an access hole in the lower wing to reach this drain with an extension wire? Or is water draining needed so infrequently that using an access panel or wingtip removal to reach the drain sufficient? There is no clear guidance in the instructions from Advanced. Appreciate any advise. Bob Alexander RV7