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
|
|||
|
|||
Any Canadians Who Can Provide Numbers on a Champ, Taylorcraft, or Luscombe with Warp Drive Propeller?
Looking for data on how much better, if any, one of the subject aircraft
performs with a Warp Drive or similiar prop. We can't install anything but certified wood props (or expensive aluminum ones) on our old birds. Thus, what we need is hard data so maybe we can approach FAA to let us convert to carbon fiber props. Information on Powerfins, Ivoprops, and anything else would be helpful too. Thanks. |
#2
|
|||
|
|||
In article , Larry Smith
wrote: Looking for data on how much better, if any, one of the subject aircraft performs with a Warp Drive or similiar prop. We can't install anything but certified wood props (or expensive aluminum ones) on our old birds. Thus, what we need is hard data so maybe we can approach FAA to let us convert to carbon fiber props. I fly a 65 hp 1945 Champ with an aluminum prop. I have seen Warp Drive props on friends Ezes. The coning scares me! Setting them to the proper angle is tricky. |
#3
|
|||
|
|||
"EDR" wrote in message ... In article , Larry Smith wrote: Looking for data on how much better, if any, one of the subject aircraft performs with a Warp Drive or similiar prop. We can't install anything but certified wood props (or expensive aluminum ones) on our old birds. Thus, what we need is hard data so maybe we can approach FAA to let us convert to carbon fiber props. I fly a 65 hp 1945 Champ with an aluminum prop. Let me guess. A 7444? 7443? McCauley or Sensenich? Those props are hard to find used and a new one is over $2500. Look in the ACS catalog. I'd like to have one on my 65hp Taylorcraft but stay with the wooden Sensenich 7442, which is much less efficient than your aluminum prop. OTOH, a Warp Drive would cost $500 and is more efficient, if what I hear from Canadian fliers with A-65's and Warp Drives on their certified birds like Champs, Chiefs, Taylorcrafts, 120's, and Luscombes is accurate. I have seen Warp Drive props on friends Ezes. The coning scares me! Setting them to the proper angle is tricky. You can set one with ease. No big deal with the right tool, just a matter of setting the same angle for each blade. Wouldn't it be nice to have a ground-adjustable prop? What's "coning"? I have never heard of a catastophic failure of one of these carbon fiber propellers. With its high strength-to-weight ratio and the characteristic stiffness of carbon, it is the ultimate material for propellers --- better than steel, aluminum, wood, or any other material. A friend of mine dinged the wooden prop on his 160 HP RV-6, and he filled the ding with JB Weld, according to the fashion. A few weeks later he's at 8500 feet when the prop section about 14" long lets go at the stress riser. He was barely able to make it back to a field and was afraid the vibration would pull the engine off the mount. Yeah, I'd go with an aluminum prop but don't want to pay 2.5k for one. Why can't I use a Warp Drive which is ground-adjustable, state-of-the-art, more efficient and costs so much less? There's something wrong here. You can buy the finest forged steel Carrillo connecting rods for a tenth of what rods cost from Teledyne Continental. TCM wants something like $800 for two connecting rods to replace condemned rods they had Cornell Forge make for them -- and which are unsafe because they disintegrate in flight, and are the subject of a TCM critical service bulletin. Something's not right. |
#4
|
|||
|
|||
On Fri, 19 Dec 2003 18:05:53 -0500, "Larry Smith"
wrote: "EDR" wrote in message ... I have seen Warp Drive props on friends Ezes. The coning scares me! What's "coning"? The prop blades bending forward...the prop disk defines a shallow cone (open end frontward, of course) under load. Ron Wanttaja |
#5
|
|||
|
|||
"Ron Wanttaja" wrote in message ... On Fri, 19 Dec 2003 18:05:53 -0500, "Larry Smith" wrote: "EDR" wrote in message ... I have seen Warp Drive props on friends Ezes. The coning scares me! What's "coning"? The prop blades bending forward...the prop disk defines a shallow cone (open end frontward, of course) under load. Ron Wanttaja Thanks. As usual the big R comes through. I've seen the phenomenon but it's not bothersome to someone knowing the great strength and elasticity modulus of carbon fiber. Where is testimony that a blade has failed? There is gossip about an Ivoprop but is it true? |
#6
|
|||
|
|||
On Sat, 20 Dec 2003 10:06:12 -0500, "Larry Smith"
wrote: "Ron Wanttaja" wrote in message .. . On Fri, 19 Dec 2003 18:05:53 -0500, "Larry Smith" Thanks. As usual the big R comes through. I've seen the phenomenon but it's not bothersome to someone knowing the great strength and elasticity modulus of carbon fiber. Where is testimony that a blade has failed? There is gossip about an Ivoprop but is it true? I have a warp drive 70" 3 blade prop on my murphy rebel with an 0-290 engine. I'm very satisfied with the prop and have had no problems with mine. It's fairly easy to change the pitch takes about an hour including retourquing and safety wiring everything. You need to check the torque on the clamp bolts every 25 hrs. There have been some reports of cracked blades on high compression engines. It's suspected that the negative power pulses at idle speed is what causes the cracking. Drew Dalgleish Centralia Ont. |
#7
|
|||
|
|||
Thanks. As usual the big R comes through. I've seen the phenomenon but
it's not bothersome to someone knowing the great strength and elasticity modulus of carbon fiber. Where is testimony that a blade has failed? There is gossip about an Ivoprop but is it true? A friend of mine has a 4 blade on his 180hp Lyc Rebel on floats. He flies all year including a annual trip to the Arctic (he's located about 100miles north of the US border so this isn't a quick trip) He had to land once on a lake with about 3-4 foot rollers when heavy (2K+) and he had spray coming over the windshield etc. Either the prop dipped into the water or something as afterwards he found one blade cracked along the root holder. He maintains his machine like a certified so he grounded the airplane and was on to warp about it pdq. They said he could fly with it as is ie it was still servicable and it wouldn't hurt anything. I think he said he only flew it a few minutes before getting too paranoid about it. He called warp and they replaced the blade for free. They said at that time his was the first damaged blade they had seen and that was in 2000. He still swears by it even though I think he's thinking about a hoffman or the like so he can nudge closer to mach 1 on floats... Even under owner maintained you won't be able to swap a warp for a certified blade. The ministry will tend to frown on such things. You could get a stc and hope they will let you spec a warp but as its not certified you are going to have to be reaaal lucky to get it through. The fee is $900 loonies plus engineering fees which means it will probably be cheaper to buy a new plane by the end f it all ;-] Q |
Thread Tools | |
Display Modes | |
|
|