Pietenpol events

Snowflakes
By Doc Mosher
BPANewsletter April 2008

Here at BPANews editorial offices, we get questions, especially from newcomers, about the political correctness of identifying certain Pietenpols. The January issue carried a front page photo of Teresa Sloan flying "Her Pietenpol." Well, we got a very well-intentioned letter pointing out that Teresa's airplane is not a Pietenpol - it is a GN-1. In the type under the photo, we said she was flying "her GN-1 Pietenpol powered by a Continental 65..." It brought to the forefront different comments we have received in the past both pro and con about the question "what actually is a Pietenpol?" which we have dutifully ignored because it sort of seemed like picking fly specks out of pepper. We all have to accede to the natural changes of language and custom. Today you do not really watch a "TV." You actually watch a TV receiver screen. Are you duty bound to correct anyone who refers to the receiver screen as a "TV"?

Fact: Bernard never built any two airplanes alike. He innovated as he went along. Even when Modern Mechanics magazine drew up "Pietenpol" plans and published them in their magazine, he surely deviated from them. After all, they weren't his plans. Wanting to generate some badly needed funds, he had young Orrin Hoopman draw up plans which Bernard then sold. These plans are the plans still being sold by Don Pietenpol after all these years - no updates, no corrections. Hoopman plans lay out the basic dimensions and sizes, but as we all know, the plans were not to aircraft specifications, and in a number of cases were in error and even lacked key dimensions. But the plans have challenged all of us to build a plane with the same frame of mind that Bernard did - with rule of thumb common sense and a realization that sometimes you have to build one or two assemblies before you get it right. Today that's not good enough for an RV or Sonex builder, but seems to satisfy most Piet builders.

Every Pietenpol that was built using these plans turned out slightly different. Here in Oshkosh, at EAA's AirVenture Museum, we have three different Pietenpols - two built by Bernard and one uncovered "here's how you do it if you follow the plans" example built by Ed Sampson, who surely knows how the originals were built by Bernard. All three are different. Is the third one, the one built by Ed really not a Pietenpol? Perhaps it's a Sampson.

Today in Oshkosh (EAA Ski Fly-in Day) it's snowing. A billion (?) snowflakes are falling in my driveway - each one is different. But they all look like snowflakes to me and each one is a beautiful individual creation. But we call each one a "snowflake" and we all know what the other guy is talking about when he says "snowflake." (Which one is an authentic snowflake?) To me, Pietenpols are an awful lot like snowflakes.

In the 1930's, Ace Corben designed his wonderful little one and two-place airplanes and sold them completed, as kits, or simply as plans. Over the years, the Corben company assets were bought and sold, and each new owner upgraded the Corben to satisfy customer requests (wider cockpit, etc.) As a result, today's Corben is a somewhat different airplane than Ace originally built.

The Pietenpol plans have remained stagnant. If you replace the tailskid with a tailwheel (1933 drawings) you no longer have an authentic Pietenpol. You've modified it from the original. If you add brakes, you have modified it more. If you put a fuel tank in the wing instead of using only the original fuselage tank, you have modified it yet again. If you lengthen the cabane struts so you can more easily get into the front cockpit, you surely have changed the aerodynamics. A new upgraded one-page addition to the original Hoopman plans was issued by Don Pietenpol in 1962 when the Corvair engine became available. The fuselage was lengthened in the cockpit area, but retained the genetic Pietenpol tailheaviness. No update there.

In November of 1951, O. G. Borstead wrote an article in EAA's Sport Aviation magazine, complete with a drawing, to advise how to safely and easily attach a Cub landing gear to a Pietenpol.

In January of 1956 Bernard said in a letter to EAA that although he did not have time to update the plans, he would appreciate if EAA would publicize some modifications that Bernard recommended. "In making the fuselage landing gear fittings, make the bottom strap go all the way across the bottom. Where the flying struts are fastened to the wing, slant the wing fittings at about the slant of the flying struts. Cub wing fittings would work swell. Some sort of stop should be put on the controls. If a 65 hp engine is used, make the fuselage just 6 inches longer in front, and make the upper engine mount fittings go back at least 3 inches further into the longeron. A complete Cub landing gear could be used to advantage." Did you have the benefit of these suggestions from Bernard in the authentic Pietenpol plans that you bought?

In the July 1957 issue of EAA's Experimenter (predecessor of Sport Aviation), is a piece (The Homebuilder's Corner) by Paul Poberezny which states: "We have a number of aircraft plans in the mill for use in the manual and to give you the word, the following are in various stages of development for future publications to members. (Several designs are mentioned, the Westphall Sport, Smith single place, Pober Sport.) [One of these is] the Pietenpol of all-wood construction, a two-place ship of which a great many were built. The plans were given to me by member Pietenpol for use by EAA and are currently being redrawn and updated by Vernon A. Eaton of Inglewood, Calif. The plans that we present will be for design consideration and as a guide to construction. The major portions of these will be published in this manual, shop size drawings of some of the more modern aircraft will be available through EAA headquarters at a nominal fee for members, while others will be returned to their originator for disposal or sale."

In August of 1960, John Grega, a talented mechanic, wrote an article for Sport Aviation called "Modernizing the Pietenpol 'Aircamper'." John and Elmer Niebecker said "We have named it the Pietenpol GN-1." They used Reed-clipped Cub wings and a Cub landing gear and replaced the Ford engine with a Continental 65. Look it up.

In the 1980s, Jim Wills, a British Pietenpol builder made new drawings for a Pietenpol which would pass the rigid engineering criteria of the British Popular Flying Association. Wills designed and built a new C-section spar, replacing the original plank or routed plank. He also made changes in the cabling control system, and used a three-piece wing utilizing a center-section in deference to the British style of smaller garages in which to build. He corresponded with Don Pietenpol about this, and received an OK from Don Pietenpol. Actually Don could not have stopped Wills from the redesign and subsequent sale of "Pietenpol" plans. Wills still named the revamped design which looked and flew almost exactly like an original American Piet "Pietenpol," and that is the name that is carried by this thoroughly re-engineered UK flying machine in the officialdom of the UK. Snowflakes in the UK look very similar to American snowflakes.

So here at BPA we admire and recognize each and every "Pietenpol type" airplane for it's separate beauty, workmanship and creative design. To us they are all snowflakes and yet one of a kind. We think Bernard would agree.