Brodhead Pietenpol Association

Original Posted By:
The photo of the airplane behind the meeting shows built-up spars of plywoodweb with apparently fir or spruce caps. Have these been described to thelist and does their design have some sort of an operational history?----- Original Message -----

Original Posted By: "bike.mike"
Wow, such attention to detail.....well, that spar design (I built it....)has been used by a few Pietenpol builders. There are a lot of detailedpictures, etc in my log on mykitplane.com.Basically, it's the same size dimensionally as the routed 1" spar built byPietenpol, except that my web is not quite 1/2" thick. The built out topand bottom (where the REAL loads are concentrated) are both 1" square afterthe build out. I used doug fir/T88 but would probably use spruce/T88 nexttime....Not sure about what would qualify as an "operational history" except to saythat I personally know of at least one "single piece" wing Air Camper thatis flying today with such a design.The calculations will likely show that building out the top and bottom to 1"square would only require a 3/16" web (with vertical stiffeners at eachrib). On paper......I'm not saying to do it that way, just that on paper it would most likelyhandle the loads.I did some destructive tests and this thing is strong.(I'm using terms like "most likely" and "will likely show" since all this ispresented as just one possible way of building a Pietenpol Air Camper spar.I obviously believe in the design MUCH more that that terminology mightindicate....)Hope this answers your question (at least to some degree).....Jim----- Original Message -----

Original Posted By: Michael D Cuy

Original Posted By: Jim Markle

Original Posted By: BARNSTMR(at)aol.com