If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
The main problem with the Ivo is extreme vibration - not the power
limitation. I never heard ANY inflight adjustable prop that would reduce cruise from 213 down to 170 - inconceivable. Its usually the other way around. H-U-G-E four bangers like the Lyc. IO-360 need very ridgid props because they induce oposing "bang" vibration and can shake the prop out of alignment. Ivo will not sell a prop for Lyc IO-360. There is no problem with 6's because they are MUCH smoother - about 120 degrees out of phase compared to 180 degrees of a four banger. Just compare any 4 cylinder car and 6 cylinder of similar size for smoothnes. Smaller engines like 0-320 do not produce as much vibration because of their smaller size. IVO props really like the 220HP Franklin because, in addition to being a 6, it has a fluid vibration damper system built into the flywheel - very smooth engine. Thats what I have in my plane. A smoother engine has important benefits - longer parts life due to less vibration. A lot of parts failures can be traced to vibration. Here are a couple of Velocities with the Franklin 220HP and IVO props: http://www.ida.net/biz/arlfrd/ (sold) http://www.lavoiegraphics.com/velocityrg/ If you don't fancy Franklin, the Continental IO-360 is also a 6 - but a little heavier. ---------------------------------------------------- Paul Lee, SQ2000 canard project: www.abri.com/sq2000 Dave S wrote in message link.net... I am involved with the building of a velocity, and questions are flying around about propeller choice. For in-flight adjustable, we are limited at this time to an electric control, such as MT or IVO. Cost is pushing our options in this area towards the IVO. I have heard of some vibration/resonance probs with certified engines (i believe it was a lycoming, but dont know specifics).. And one emailer has mentioned when they used the engine on a mazda powered a/c they were limited to 170 mph with the IVO but got 213 mph with a cruise wood prop. I am looking for any other experiences.. good bad or otherwise regarding the IVO inflight adjustable props (particularly in the 200 hp range). Experiences with any other electrically controlled props that can handle 200-220 hp would be welcome too.. but the MT is probably outside my price range.. Dave |
#3
|
|||
|
|||
Since the hub area of the prop is "supposed" to be stationary, why can't
the hub area of the CF blades be wrapped in multiple layers of CF and then bolted on as a "One piece" prop. Granted the individual blades couldn't be removed later, but the price for three blades appears that replacing them all at once would still be cost effective? Also - anyone have more info on the 3 Rotor, 4P at Copperstate? Scott V. H-U-G-E four bangers like the Lyc. IO-360 need very ridgid props because they induce oposing "bang" vibration and can shake the prop out of alignment. Ivo will not sell a prop for Lyc IO-360. There is no problem with 6's because they are MUCH smoother - about 120 degrees out of phase compared to 180 degrees of a four banger. Just compare any 4 cylinder car and 6 cylinder of similar size for smoothnes. Smaller engines like 0-320 do not produce as much vibration because of their smaller size. IVO props really like the 220HP Franklin because, in addition to being a 6, it has a fluid vibration damper system built into the flywheel - very smooth engine. Thats what I have in my plane. A smoother engine has important benefits - longer parts life due to less vibration. A lot of parts failures can be traced to vibration. |
#4
|
|||
|
|||
Scott,
I was the person that saw the 4P with the 3 Rotor Mazda at Copperstate. It looked like it was just finished and still was in primer. A few details needed to be cleaned up but it looked like it was built solidly. Any questions a person who just "took a look" could answer for you just write me at my email address. Bart -- Bart D. Hull Tempe, Arizona Check http://www.inficad.com/~bdhull/engine.html for my Subaru Engine Conversion Check http://www.inficad.com/~bdhull/fuselage.html for Tango II I'm building. Scott VanderVeen wrote: Since the hub area of the prop is "supposed" to be stationary, why can't the hub area of the CF blades be wrapped in multiple layers of CF and then bolted on as a "One piece" prop. Granted the individual blades couldn't be removed later, but the price for three blades appears that replacing them all at once would still be cost effective? Also - anyone have more info on the 3 Rotor, 4P at Copperstate? Scott V. H-U-G-E four bangers like the Lyc. IO-360 need very ridgid props because they induce oposing "bang" vibration and can shake the prop out of alignment. Ivo will not sell a prop for Lyc IO-360. There is no problem with 6's because they are MUCH smoother - about 120 degrees out of phase compared to 180 degrees of a four banger. Just compare any 4 cylinder car and 6 cylinder of similar size for smoothnes. Smaller engines like 0-320 do not produce as much vibration because of their smaller size. IVO props really like the 220HP Franklin because, in addition to being a 6, it has a fluid vibration damper system built into the flywheel - very smooth engine. Thats what I have in my plane. A smoother engine has important benefits - longer parts life due to less vibration. A lot of parts failures can be traced to vibration. |
#5
|
|||
|
|||
Can't speak specifically on IVO, although he's in my area and have
thought it might be interesting to stop by the factory and see whats what. I like the flexibility with which you can configure the props. One thing that you've probably already heard, but I'll restate for other readers, is that, on a canard, the prop lives in the downwash of the wing and turbulence off the fuselage. As a result, each blade is experiencing changing forces as it goes round and round. Over time this may effect the endurance of the prop. This is in contrast to a coventional tractor configuration where the prop is biting into clean air. So I've heard wood props are the thing for canards for at least that reason. Dave S wrote in message link.net... I am involved with the building of a velocity, and questions are flying around about propeller choice. For in-flight adjustable, we are limited at this time to an electric control, such as MT or IVO. Cost is pushing our options in this area towards the IVO. I have heard of some vibration/resonance probs with certified engines (i believe it was a lycoming, but dont know specifics).. And one emailer has mentioned when they used the engine on a mazda powered a/c they were limited to 170 mph with the IVO but got 213 mph with a cruise wood prop. I am looking for any other experiences.. good bad or otherwise regarding the IVO inflight adjustable props (particularly in the 200 hp range). Experiences with any other electrically controlled props that can handle 200-220 hp would be welcome too.. but the MT is probably outside my price range.. Dave |
#6
|
|||
|
|||
|
#7
|
|||
|
|||
The two IVO/Franklin 220HP successfull combos I mentined - N6Q and N570 -
are both canards. The IVO installation instructions mention that the prop tip is expected to flex as much as 4". (Jay) wrote in message . com... ........... One thing that you've probably already heard, but I'll restate for other readers, is that, on a canard, the prop lives in the downwash of the wing and turbulence off the fuselage. As a result, each blade is experiencing changing forces as it goes round and round. Over time this may effect the endurance of the prop. This is in contrast to a coventional tractor configuration where the prop is biting into clean air. So I've heard wood props are the thing for canards for at least that reason. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Comments on new design carbon aircraft kit? | lifespeed | Home Built | 2 | December 3rd 03 03:22 PM |
Props? | Toks Desalu | Home Built | 2 | November 13th 03 09:39 AM |
Hegy Wood Props webpage | HEGYPROPS | Home Built | 0 | October 16th 03 04:50 PM |
Props and Wing Warping... was soaring vs. flaping | Wright1902Glider | Home Built | 0 | September 29th 03 03:40 PM |
Ivo Props | BRUCE FRANK | Home Built | 2 | August 6th 03 03:43 AM |