Pietenpol-List Digest Archive

Sat 01/31/04


Total Messages Posted: 12



Today's Message Index:
----------------------
 
     1. 06:16 AM - Re: Long-range planning (Mark Hodgson)
     2. 07:27 AM - Re: videos (Jim Markle)
     3. 07:35 AM - OT....sorry...... videos (Jim Markle)
     4. 08:19 AM - Re: Long-range planning (Carbarvo@aol.com)
     5. 09:01 AM - Re: Long-range planning (Kevin Holcomb)
     6. 12:17 PM - Re: corvair conversion cost (Norman Stapelberg)
     7. 01:33 PM - Re: more airfoil talk (Mike Whaley)
     8. 03:31 PM - Fuel Tanks & Flying Story. (Rcaprd@aol.com)
     9. 04:45 PM - Re: Fuel Tanks & Flying Story. (Peter W Johnson)
    10. 07:18 PM - Re: Graham ! (and idea for storage in a Piet for x-country travel)  (Graham Hansen)
    11. 08:27 PM - Re: Re: more airfoil talk (Rcaprd@aol.com)
    12. 09:07 PM - Re: Re: more airfoil talk (dave rowe)
 
 
 


Message 1


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    Time: 06:16:09 AM PST US
    From: Mark Hodgson <mhodgson@bu.edu>
    Subject: Re: Long-range planning
    --> Pietenpol-List message posted by: Mark Hodgson <mhodgson@bu.edu> Thanks again to the list for all the responses! This answers the main question--"am I going to get killed financially AFTER the Piet's paid for, rather than before?" Looks like there are a number of good options (all involving protecting the structure in some way, of course). I've got plenty of time to sort that out, and have several interesting leads to follow up on in this Piet-scarce area. Hope I can get to Brodhead again this year, BTW. Mark do not archive


    Message 2


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    Time: 07:27:27 AM PST US
    From: "Jim Markle" <jim_markle@mindspring.com>
    Subject: videos
    Burning the CD now.....do you have a cell phone? Or we can just meet at the museum..... cu later my cell: 469-371-0669 -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Clif Dawson Sent: Saturday, January 31, 2004 12:00 AM To: pietenpol-list@matronics.com Subject: Re: Pietenpol-List: videos Absolutely!! That's it! Thats great! A CD will be just fine. Thank you Jim. --> Pietenpol-List message posted by: Jim Markle Do you mean the site that had a lot of jpg's and a bunch of short video clips? I copied them (and the entire site, actually) before the site went down.....if that's the one you're referring to.... I'll burn a CD for you and bring it this weekend. If you prefer DVD, let me know. do not archive


    Message 3


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    Time: 07:35:41 AM PST US
    From: "Jim Markle" <jim_markle@mindspring.com>
    Subject: videos
    My apologies to everyone....I meant to send this offline....oops jm -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Jim Markle Sent: Saturday, January 31, 2004 9:27 AM To: pietenpol-list@matronics.com Subject: RE: Pietenpol-List: videos Burning the CD now.....do you have a cell phone? Or we can just meet at the museum..... cu later my cell: 469-371-0669 -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com]On Behalf Of Clif Dawson Sent: Saturday, January 31, 2004 12:00 AM To: pietenpol-list@matronics.com Subject: Re: Pietenpol-List: videos Absolutely!! That's it! Thats great! A CD will be just fine. Thank you Jim. --> Pietenpol-List message posted by: Jim Markle Do you mean the site that had a lot of jpg's and a bunch of short video clips? I copied them (and the entire site, actually) before the site went down.....if that's the one you're referring to.... I'll burn a CD for you and bring it this weekend. If you prefer DVD, let me know. do not archive


    Message 4


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    Time: 08:19:07 AM PST US
    From: Carbarvo@aol.com
    Subject: Re: Long-range planning
    Pieters: The light at the end of the tunnel has alerted me to a need to house this airplane somewhere. I have gotten interested in a company from Boone, NC named US-Buildings..(800/463-6062). They have five styles of steel buildings which appear to be simple to erect..(unlike some other aspects of my life). One of these styles is reminiscent of B. Pietenpols hanger in Cherry Grove (now at Oshkosh). I would be very interested to hear of any experiences any of you may have with this company or with this style of building. At the prices they were quoting, I figure it will pay for itself within five years............CAVU Carl Vought


    Message 5


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    Time: 09:01:19 AM PST US
    From: "Kevin Holcomb" <ksholcomb@mindspring.com>
    Subject: Re: Long-range planning
    MARKETING_SUBJECT, MIME_BOUND_NEXTPART I recently purchased a 50x50 straight sided quonset hut. There are a number of companies with very similar products, all of them reluctant to initially quote a price but eager to beat their competitors price. Spend a few months and play them off each other. My experience was that the 'special, good this week only price' was still available the next month. Expect a lot of carrying on, 'special deals', 'buy now before the price of steel goes up', etc from the salesmen. Ignore all of the carrying on and just keep going back and forth. The final price I paid was about half of the first quote I received. My building is not complete yet, so far 17 out of 25 arches are up. I started on Dec 26 and have worked evenings and weekends as I have a day job. An arch per full day of work is about what it works out to. Mostly it has just been my wife and I; you will need someone to hold the nuts. At least with my building (which is 50 ft wide and thicker than usual to meet Florida's wind codes) I found the instructions that show the arches being assembled on the ground to be a joke as the arches would buckle under their own weight. Instead I have been building the arches in place. With large holes in the metal and small bolts most of them go through with little trouble. A couple of drift pins help a lot. When you price the job out do not forget to add in the concrete for the pad as that came to around 2/3 the cost of my building. Also expect to rent a man lift (scissor type) for a couple of months during assembly and a forklift for a day to unload the truck when it arrives. Doo rs are also quite expensive. The good news is that there are no difficult skills to master, no heavy lifting, and little heavy equipment. A frame steel building with siding would probably have gone together faster, however that would have involved heavy equipment that I do not have. The thought of a collection of 50 ft beems being dropped in my yard and having to figure out how to get them in position 16 feet in the air makes a quonset look great to me. Kevin www.airminded.net ----- Original Message ----- From: Subject: Re: Pietenpol-List: Long-range planning Pieters: The light at the end of the tunnel has alerted me to a need to house this airplane somewhere. I have gotten interested in a company from Boone, NC named US-Buildings..(800/463-6062). They have five styles of steel buildings which appear to be simple to erect..(unlike some other aspects of my life). One of these styles is reminiscent of B. Pietenpols hanger in Cherry Grove (now at Oshkosh). I would be very interested to hear of any experiences any of you may have with this company or with this style of building. At the prices they were quoting, I figure it will pay for itself within five years............CAVU Carl Vought


    Message 6


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    Time: 12:17:42 PM PST US
    From: "Norman Stapelberg" <norshel@mweb.co.za>
    Subject: corvair conversion cost
    --> Pietenpol-List message posted by: "Norman Stapelberg" <norshel@mweb.co.za> Sorry just downloaded my messages; I should have also said that I am running a Lycoming 0-235. When my test pilot did his test he got 2000RPM static and unloaded to 2100RPM in the take of roll, he did a dive down to the runway and she unloaded to 2200RPM at a max of 75kts, cruised at 55kts 2100RPM. I agree that I have to much prop, I just got back home from the previous owner, he gave me one of the previous props that was on the plane a GSC 72" dia, the original owner no longer has any of the props he had tested on her. Just some history, the plane did a nose over on landing in about 1984 and had not flown since, she has been recovered and the motor has been majored with all the mandatory mods done. The 0-235 has of date 10Hrs since major, airframe has 1.3Hrs since major. << Also what pitch and dia should I be using(currently 72X48) and only getting 2000RPM >> Norman, Most of the Continental A65's that I've seen, including mine, has a 72 X 42 wooden prop. Sounds like you have too much prop. Is that you on the business end, or in the driver's seat ? Chuck Gantzer NX770CG


    Message 7


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    Time: 01:33:24 PM PST US
    From: "Mike Whaley" <MerlinFAC@cfl.rr.com>
    Subject: Re: more airfoil talk
    --> Pietenpol-List message posted by: "Mike Whaley" <MerlinFAC@cfl.rr.com> > it would be cool to have multiple wings (the standard set, a pair of > speeders, a super high lift set, etc.), depending on the day's application. > It would be the Swiss army knife of AirCampers. The heck with this 3-piece wing stuff. How about a 12-piece wing. Just pick the speed you want to fly and take off as many sections as you dare. When you can't lift off anymore, you went one step too far. :)


    Message 8


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    Time: 03:31:50 PM PST US
    From: Rcaprd@aol.com
    Subject: Fuel Tanks & Flying Story.
    --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/30/04 11:55:41 PM Central Standard Time, vk3eka@bigpond.net.au writes: << Thanks Chuck, I presume the cowl tank would have to have a level indicating the capacity of the wing tank. This would allow the cowl tank to use enough fuel to enable the wing tank valve to be turned on and re-fill the cowl tank without overflowing the cowl tank. Unless there was a float valve on the cowl tank inlet from the wing tank. I think may be a better idea would be to have the fuel valves on each tank seperatley feeding the gascolator. You would also need some sort of wing tank quantity guage. What do you think? >> Peter, The beauty of a Pietenpol is in it's simplicity. Keep it simple. If it isn't there, it can't break or leak. Bernard Harold Pietenpol maintained this strategy throughout. He simply valved the line from the wing tank to the cowl tank. Use 3/8" aluminum fuel lines and 37 flaired aircraft grade 'B' nuts throughout. You also need a 'Finger Screen' in the outlet of each tank. This is your third line of defense against getting crap in the carb. First line of defense is use clean fuel, during re-fuel operation, and during storage, you also need to cap the L shaped vent, with a flag that says 'Remove Before Flight'. For some reason, wasps and other bugs don't seem to mind the odor of fuel. Fourth line of defense is the fine mesh screen in the gascolator, and finally the Very Fine screen in the inlet of the carburetor. The Cowl tank is in fact the main tank. The Wing tank simply replenishes the cowl tank, when you see the level of the wire / cork get low enough. In flight, there is no need to see the quantity of the wing tank. This system does, however, require fuel management during flight, because you can overflow the cowl tank during an in flight re-fuel period. Ya gotta keep an eye on the wire, during re-fuel. Pre-flight fuel quantity indicator is a dip stick, one end for the cowl tank, the other end of the stick is for the wing tank. To make the stick, have the plane on level ground, and tail down. Start out with an empty tank, and add 1 gallon increments, dip and mark the quantity on the stick at each gallon line. During each pre-flight, record the 'Fuel Onboard' in your pre-flight log, along with the time, date, hour meter, etc. Check all this again at post flight, and this enables you to determine your fuel burn rate. I have a flying story about this system: On my way back from Oshkosh last year, I was 30 miles southeast of Kansas City, and the wire in the cowl tank showed me I was low enough to add some fuel. Any time you move any fuel valve in any airplane, you should be within gliding distance of an airport. I had a small airport within sight, so I reached up and turned the wing tank valve on, and settled back to enjoy the scenery and unparalleled beauty of flying an open cockpit plane. It takes over 6 minutes to empty my wing tank, and although I glanced at the wire as it came up, I thought the entire contents of the wing tank, would fit in the cowl tank. NOT !! A 1/4" stream of fuel began squirting out of the cowl tank vent, and instantly covered my windshield with FUEL ! I squinted my eyes, reached up and turned the valve off, went full power climb to try to use more fuel. Ducked down in behind the windshield, with eyes squinted, I watched the left wing tip to maintain wing level, and watched the airspeed to maintain a steep climb rate. I was afraid of getting fuel in my eyes, which would have been DISASASTEROUS !! It took about minute or so, before the fuel stopped covering my windshield. Whew !! That was a close one !! Lesson Learned !! Chuck Gantzer NX770CG


    Message 9


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    Time: 04:45:27 PM PST US
    From: "Peter W Johnson" <vk3eka@bigpond.net.au>
    Subject: Fuel Tanks & Flying Story.
    --> Pietenpol-List message posted by: "Peter W Johnson" <vk3eka@bigpond.net.au> Chuck, Sounds like fun!!! As I noted, a mark on the cowl fuel tank contents level to show when there is enough space in the tank to take the contents of the wing tank would be useful. Thanks for the suggestions. Peter. -----Original Message----- From: owner-pietenpol-list-server@matronics.com [mailto:owner-pietenpol-list-server@matronics.com] On Behalf Of Rcaprd@aol.com Subject: Pietenpol-List: Fuel Tanks & Flying Story. --> Pietenpol-List message posted by: Rcaprd@aol.com In a message dated 1/30/04 11:55:41 PM Central Standard Time, vk3eka@bigpond.net.au writes: << Thanks Chuck, I presume the cowl tank would have to have a level indicating the capacity of the wing tank. This would allow the cowl tank to use enough fuel to enable the wing tank valve to be turned on and re-fill the cowl tank without overflowing the cowl tank. Unless there was a float valve on the cowl tank inlet from the wing tank. I think may be a better idea would be to have the fuel valves on each tank seperatley feeding the gascolator. You would also need some sort of wing tank quantity guage. What do you think? >> Peter, The beauty of a Pietenpol is in it's simplicity. Keep it simple. If it isn't there, it can't break or leak. Bernard Harold Pietenpol maintained this strategy throughout. He simply valved the line from the wing tank to the cowl tank. Use 3/8" aluminum fuel lines and 37 flaired aircraft grade 'B' nuts throughout. You also need a 'Finger Screen' in the outlet of each tank. This is your third line of defense against getting crap in the carb. First line of defense is use clean fuel, during re-fuel operation, and during storage, you also need to cap the L shaped vent, with a flag that says 'Remove Before Flight'. For some reason, wasps and other bugs don't seem to mind the odor of fuel. Fourth line of defense is the fine mesh screen in the gascolator, and finally the Very Fine screen in the inlet of the carburetor. The Cowl tank is in fact the main tank. The Wing tank simply replenishes the cowl tank, when you see the level of the wire / cork get low enough. In flight, there is no need to see the quantity of the wing tank. This system does, however, require fuel management during flight, because you can overflow the cowl tank during an in flight re-fuel period. Ya gotta keep an eye on the wire, during re-fuel. Pre-flight fuel quantity indicator is a dip stick, one end for the cowl tank, the other end of the stick is for the wing tank. To make the stick, have the plane on level ground, and tail down. Start out with an empty tank, and add 1 gallon increments, dip and mark the quantity on the stick at each gallon line. During each pre-flight, record the 'Fuel Onboard' in your pre-flight log, along with the time, date, hour meter, etc. Check all this again at post flight, and this enables you to determine your fuel burn rate. I have a flying story about this system: On my way back from Oshkosh last year, I was 30 miles southeast of Kansas City, and the wire in the cowl tank showed me I was low enough to add some fuel. Any time you move any fuel valve in any airplane, you should be within gliding distance of an airport. I had a small airport within sight, so I reached up and turned the wing tank valve on, and settled back to enjoy the scenery and unparalleled beauty of flying an open cockpit plane. It takes over 6 minutes to empty my wing tank, and although I glanced at the wire as it came up, I thought the entire contents of the wing tank, would fit in the cowl tank. NOT !! A 1/4" stream of fuel began squirting out of the cowl tank vent, and instantly covered my windshield with FUEL ! I squinted my eyes, reached up and turned the valve off, went full power climb to try to use more fuel. Ducked down in behind the windshield, with eyes squinted, I watched the left wing tip to maintain wing level, and watched the airspeed to maintain a steep climb rate. I was afraid of getting fuel in my eyes, which would have been DISASASTEROUS !! It took about minute or so, before the fuel stopped covering my windshield. Whew !! That was a close one !! Lesson Learned !! Chuck Gantzer NX770CG advertising on the Matronics Forums.


    Message 10


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    Time: 07:18:09 PM PST US
    From: "Graham Hansen" <grhans@cable-lynx.net>
    Subject: Re: Graham ! (and idea for storage in a Piet for x-country
    travel) --> Pietenpol-List message posted by: "Graham Hansen" <grhans@cable-lynx.net> Michael, For years, I used a metal cover over the front cockpit in cooler weather and, when the a/c was hangared, keep out pests of various kinds. The sheet metal covers were fine, but I had leave them at home when I went anywhere, so I had covers made from fabric material used for sailboat sail covers. Snap fasteners hold them in place and they can be rolled up and taken with the airplane in the wing center section which has always been the small baggage compartment on my Pietenpol (I have only the fuselage nose tank holding about 15 US gallons of fuel). I have never flown really long distances with my Pietenpol, but on occasion have removed the front stick and secured stuff onto the front seat using the lap belt and shoulder straps. I have thought of making a canvas sling, similar to yours, but never got around to doing so. I find the Pietenpol uncomfortable after about an hour "in the saddle" and like to land for a little "walkabout" after perhaps 1.5 hours. If some extra fuel is required, I strap a 5 gallon container onto the front seat and empty it into the fuel tank during such a stop. I have always preferred to use only the top half of the fuel in the tank, and to not make serious demands on the lower half. So these stops fit my philosophy nicely. At one time I was inclined to fly my Pietenpol to Oshkosh and/or Brodhead, but never got things arranged so that I could get away. Nowadays, I am too old for such an undertaking (Hint: I am the same age as the Pietenpol design) and the distance is simply too great. If I lived closer, say within 500 to 600 miles, you would see me there, but 1600 to 1700 miles is at this stage a bit much. Besides, border crossings have become a hassle and clearing Canadian Customs when returning is awkward because many airports of entry are no longer available on this side. With the Piet's limited range there could be problems and I just don't need that sort of thing! Many years ago (It now seems to be in another life) I used to fly old Bell helicopters from Edmonton to the northern Yukon, Northwest Territories and Arctic coast, and back again. Those Bell 47s were even slower than my Pietenpol, but we had practically unlimited places to land and didn't have to play the Customs game. It was somewhat tiresome going north in the spring, but much more pleasant when returning in the autumn. Today, people like Ted ("Iron Butt") Brousseau can do the honors in my place! Thanks for the tips, Mike. Cheers, Graham (Pietenpol CF-AUN in chilly Alberta, where we now have LOTS of snow for ski flying.)


    Message 11


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    Time: 08:27:57 PM PST US
    From: Rcaprd@aol.com
    Subject: Re: more airfoil talk
    --> Pietenpol-List message posted by: Rcaprd@aol.com Corky, Robert, et all, When you change anything in an aircraft design, you will change a host of other things, especially if it's the airfoil that you consider changing. The 'French Curve, Ten Minute' (FC-10) airfoil has been designed into the Pietenpol for very good reasons. It allows the C.G. to be further aft, than any airfoil that is not undercambered. It's a High Lift airfoil, that allows a low power engine to be used. The down side of the high lift, is that it is High Drag. The overall high drag of the Pietenpol also has it's advantages...it's difficult to achieve a high enough speed for flutter to occur. None of the flight control surfaces of a Pietenpol are mass balanced. If a more efficient airfoil is used on the Pietenpol, higher speed will result. This higher speed, will certainly approach the speed at which one of the control surfaces will flutter. B.H.P. called out the Vne of the Piet at 90 m.p.h., and must be adhered to. On three separate occations, I've wittnessed a model R.C. airplane flutter one of the control surfaces. I could hear the sound - z z z Z Z Z Z as it went past, and it took just a couple of seconds before the control surface tore itself loose from the plane, and the plane crashed into hundreds of pieces. On two separate occasions, I've witnessed the results of an aft C.G. on a model R.C. airplane. These two planes were of aerobatic design, and maintaining the C.G. at the aft limits allows the plane to be Very agile, and also increases it's efficiency. Both times, the pilot thought he would be all right with the C.G. just a tiny bit behind the aft limit, and after entering a spin, the plane would not come out of the spin, no matter what the pilot did with the stick or power setting, and the model airplane spun all the way to the ground, with disastrous results. The Grega G1 has a larger radius on the leading edge, in an attempt to soften the stall break. It's actually the rapid increase in 'Induced Drag' that causes the Pietenpol to slow down quickly, and surpass the 'Critical Angle of Attack. 'Parasite Drag' is at it's minimum during the slow flight of the Landing. On prototype certified aircraft, they have some underpaid experimental test pilot, take the plane up for flutter tests. He dives it, in incremental speed increases, until one of the control surfaces begins to flutter, and immediately pulls power and eases the nose up, to slow down. If his prayers are answered, the control surface will still be attached to the aircraft. The designer then reduces this speed by 25%, and this is the Vne of the aircraft. If anything is changed to any of the flight control system, these flutter tests must be re-done. Steve Wittman did these flutter tests on his design, down very close to the frozen Lake Michigan. If a control surface would flutter and come off, he would land at a very high speed, and slide to a stop. I don't believe it ever did happen, though. Talk about Big Kahoona's !!!! I am all for experimenting, and learning as much as possible as to why things are designed the way they are, but you must understand all the consequences before you make any changes to the aircraft. Chuck Gantzer NX770CG


    Message 12


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    Time: 09:07:32 PM PST US
    From: dave rowe <rowed044@shaw.ca>
    Subject: Re: more airfoil talk
    --> Pietenpol-List message posted by: dave rowe <rowed044@shaw.ca> Amen. A lot of us R/C guys have experimented and seen the results. Much cheaper and the only thing hurt is our wallets! We once tried overpowering our club piper clipped-wing cubs, and quickly tore the horzontal stab from one. It took a complete redesign to allow us to fly with the power we wanted for doing crazy things. I also experienced flutter with a unlimited Sukhoi, fortunately just lost one elevater, and was able to land without further incident! If you want to screw around, build an R/C Pietenpol and have a blast, cheap way of trying new things! I'm sure DJ Vegh will volunteer his . . . Rcaprd@aol.com wrote: > > --> Pietenpol-List message posted by: Rcaprd@aol.com > > Corky, Robert, et all, > When you change anything in an aircraft design, you will change a host of > other things, especially if it's the airfoil that you consider changing. The > 'French Curve, Ten Minute' (FC-10) airfoil has been designed into the > Pietenpol for very good reasons. It allows the C.G. to be further aft, than any > airfoil that is not undercambered. It's a High Lift airfoil, that allows a low > power engine to be used. The down side of the high lift, is that it is High > Drag. The overall high drag of the Pietenpol also has it's advantages...it's > difficult to achieve a high enough speed for flutter to occur. > None of the flight control surfaces of a Pietenpol are mass balanced. If > a more efficient airfoil is used on the Pietenpol, higher speed will result. > This higher speed, will certainly approach the speed at which one of the > control surfaces will flutter. B.H.P. called out the Vne of the Piet at 90 > m.p.h., and must be adhered to. > On three separate occations, I've wittnessed a model R.C. airplane > flutter one of the control surfaces. I could hear the sound - z z z Z Z Z Z as it > went past, and it took just a couple of seconds before the control surface tore > itself loose from the plane, and the plane crashed into hundreds of pieces. > On two separate occasions, I've witnessed the results of an aft C.G. on a > model R.C. airplane. These two planes were of aerobatic design, and > maintaining the C.G. at the aft limits allows the plane to be Very agile, and also > increases it's efficiency. Both times, the pilot thought he would be all right > with the C.G. just a tiny bit behind the aft limit, and after entering a spin, > the plane would not come out of the spin, no matter what the pilot did with > the stick or power setting, and the model airplane spun all the way to the > ground, with disastrous results. > The Grega G1 has a larger radius on the leading edge, in an attempt to > soften the stall break. It's actually the rapid increase in 'Induced Drag' that > causes the Pietenpol to slow down quickly, and surpass the 'Critical Angle of > Attack. 'Parasite Drag' is at it's minimum during the slow flight of the > Landing. > On prototype certified aircraft, they have some underpaid experimental > test pilot, take the plane up for flutter tests. He dives it, in incremental > speed increases, until one of the control surfaces begins to flutter, and > immediately pulls power and eases the nose up, to slow down. If his prayers are > answered, the control surface will still be attached to the aircraft. The > designer then reduces this speed by 25%, and this is the Vne of the aircraft. If > anything is changed to any of the flight control system, these flutter tests > must be re-done. Steve Wittman did these flutter tests on his design, down > very close to the frozen Lake Michigan. If a control surface would flutter and > come off, he would land at a very high speed, and slide to a stop. I don't > believe it ever did happen, though. Talk about Big Kahoona's !!!! > I am all for experimenting, and learning as much as possible as to why > things are designed the way they are, but you must understand all the > consequences before you make any changes to the aircraft. > > Chuck Gantzer > NX770CG > > > > > >




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