Brodhead Pietenpol Association

Original Posted By: Michael Perez

Original Posted By: Michael Perez

Original Posted By: H RULE

Original Posted By: Ryan Mueller
Subject: Re: Pietenpol-List: Something other then cables

Original Posted By: Tim Willis

Original Posted By: "Michael Perez"
I used to work for Steen Aero, the sole North American importer from whomall these streamlined flying wires come into this country before going toAS&S, Wicks, etc. While these things have impressive virtues and are vitallyimportant when used in the proper application, I wouldn't dream of usingthem on a Pietenpol, or in fact on any plane where I didn't actually have touse them!First off, these wires are all custom-made in Scotland by Brunton's, with a12+ week lead time because they are all essentially hand-crafted. If youchange something on your plane and a wire length changes beyond the abilityof the fittings to compensate, you have to buy a new piece, and they're NOTreturnable or refundable, unless the factory actually screwed up theirmanufacture (that's rare). A set of wires and fittings for a typical 2-placehomebuilt biplane generally costs WELL north of $12,000, depending uponexchange rates (which are much worse nowadays). Even just the tail wires fora Piet would probably cost as much as most of the rest of the plane!Also, there have been crashes caused by improper substitution of solidstreamlined flying wires in an aircraft that was originally designed forregular round cables. Solid wires are much stiffer than cable, and whenimproperly used, a steady vibration mode can occur. Where the cable willjust vibrate with no discernable effect, a solid wire will flex and focusthe shaking at "nodes" dependent upon the length of the wire, the loading,and the frequency and waveform of the vibration. They then get metal fatigueand eventually the wire fractures clean in half... usually at the worst timepossible!Sometimes, these wires are necessary and vitally important, but in the caseof the Pietenpol, it just doesn't make much sense either cost-wise orstrength-wise or IMHO risk-wise. If I had a Skybolt, I'd certainly notconsider using anything but these, but then it was designed that way fromthe start.As for drag, well... if you really wanna clean up a Piet to go significantlyfaster, you might try making it out of molded carbon fiber to get the weightdown, put a full canopy on it, switch to a cantilever wing with a newairfoil, stuff 250 hp into it, and add retracts. You *might* break 100 mph!-MikeMike WhaleyMerlinFAC(at)cfl.rr.com----- Original Message -----

Original Posted By: Michael Perez

Original Posted By: "Bill Church"

Original Posted By: "Cuy, Michael D. (GRC-RXD0)[ASRC Aerospace Corporation]"
Hey Tim; I'm in central Texas also. Where are you? Not sure about your e-mail addressbut here is mine.will(at)cctc.netWillRead this topic online here:http://forums.matronics.com/viewtopic.p ... __________