Hi
I want to thank you for responding.
I assure you this will not be my first build, I am an experienced A&P mechanic and a certified commercial pilot, but I wish to build something that I cannot be arbitrarily prohibited from flying at my leisure from my own property.
I have purchased the RW-1 plan set from Mr Mann, and have considered it. I have also participated in the construction of a Kimbrel Banty and a modification of Mann's RW-5 Heath Replica (so I have studied the RW-4, 5, 6, and 7 plans). If the Part 103 weight limit was just a smidge higher, say 280 pounds, or if the stall speed worksheet allowed for the use of actual weights instead of standard weights I could simply build either an AC or a SS pretty much to plans.
Working the numbers, I know that this is all possible, and would love to hear from anyone who has done any of these things.
(1) Getting into and out of the "vehicle" without a flop or half-door.
(2) Using the "Cub" or AC wooden landing gear.
(3) Using an "automobile leaf spring" tail skid, a fiberglass tail skid, or the "V" SS tail skid. (Grass field)
Holding certification necessary to my employment, I wish to avoid potential conflicts over (mis)interpretations of rules that are often often contradictory with one another, I am choosing to use the most restrictive interpretation of each espoused rule.
My desire is to build what I consider a "real" Pietenpol, using the "official plans" I purchased from Andy. But like most everybody I will add my own personality to the build.
I have performed three complete analysis of the aerodynamic loads, weights, and balances of the RW-1, SS, and AC. I'm not knocking the RW-1, but my primary issue with the design is that it seems to be designed for ease of production-- odd for something being individually produced. The Pietenpol has to my mind a much superior stress analysis. The RW-1 appears to be safe, but the Piet should be able to take grater loads because the structure is designed to carry the actual local loads.
Again regulations require a minimum level of safety while simultaneously prohibiting improvements over that minimum level.
Look at the wing and empennage plans, without mathematics you can see that the Piets have dimensions based on aerodynamic load. The RWs are designed for symmetry and interchangibility. Their structure is uniform-- but the loads are not. It's like a chain being lowered from a tower. Ideally the upper links should be stronger than the lower links (because they must support the lower links as well as what is at the end of the chain.)
On the RW some parts are overbuilt (which due to regulations is a weight concern). Since failure will occur at the weakest point-- and I don't work for an airport authority that installs a twenty foot wide, ten foot tall gate with razor wire, electronic locks, and a remote video surveliance system, in the middle of an unlighted mile of 36 inch high spit rail fencing around the airport and declare the place secure-- at the very least repositioning the RW's parts will increase the strength of the structure.
Even my 1930 AC plan differs a bit from my 1933 AC plan (I rather like the aesthetics of the squared-off horizontal stabilizer). BHP himself revised the front end for the lighter Continental and Corvair powerplants. There were approximately 900 variations on landing gear design (I rather like the "stock" three point SS design-- I hope Pilatus is sending Andy royalties
). Moving the fuel tank and adding a half door are in the plans. There is an "official" plan to extend the fuselage and to to move the pilots seat back to accomidate a taller pilot, people have extended the lift struts and increased their rake.
I submit that these are all "real" Pietenpols.
When you look at the center of lift and the center of gravity the SS is just a slightly scaled down AC that only seats a single occupant-- important because notwithstanding the fact that anything mechanical can be modified-- to be compliant a ULV cannot be "modified" to hold a second occupant. (Heck years ago I "rebuilt" a certified Aeronca AC-2 from an "airworthy" dataplate and a pile of rusty metal.) The SS has about a six inch shorter fuselage with one less frame than the AC. The front has been effectively extended five inches by raking back the lift struts. Each tail surface is about five inches shorter.
The AC was balanced for fight. With fuel and a passenger if there was one carried on the CG. With lighter air cooled engines BHP extended the nose of both the AC and SS forward. I weigh 125 pounds and am 5' 5" tall. I must move the seat forward or move the controls back. Moving me forward about five or six inches places me in an ideal position with the flight controls "per plan," and it moves the CG forward.
I'll revise my language in the earlier post but I intended to either build the "vehicle" in it's entirety to a scale (IE 95%) or to build a single occupant aircraft of the AC layout to (full or scaled) SS size. I never intended to "willy-nilly" resize things and invalidate the engineering already performed. (I am greatly concerned that building a scaled down (IE 90%) AC would be a regulatory 'Trojan Horse' because I could obviously simply add a front cockpit after certifying it's weights.)
So on to particulars: (I have completed my modeling since my initial post.)
(1) Pilot position will be moved forward about five to six inches in the SS (official plans show how to do the opposite).
(2) The "flop" will be eliminated regardless of which "vehicle" is built (a minor modification).
(3) The wing will be built without a cutout, with a full center rib, and without the fuel tank or its supports (per official plans).
(4) Inner compression struts will be relocated inboard about 1.5 inches each to allow the lift struts to remain at a 90 degree angle.
(5) The width and maximum height of the aircraft fuselage will be decreased from 24 to 21 inches.
(6) The motor mount will be extended forward a little, I need to do a mock-up to determine exactly how much based on alternative arrangements of the muffler and other items as well as the increased weight from the longer mount (there are multiple official engine mounts, one will be adaptable).
(7) On an AC pattern "vehicle" the SS wing would be used (making it a "Sky Camper?)
(8) On an AC pattern "vehicle" the fuselage will be of SS length and have the SS lift strut rake. (Air Scout?)
Any opinions or ideas are welcome.
Jacqueline