Availability Of Replacement Outside Longerons

[ryanclub]

Members of the IRC are being offered the opportunity to support the creation of tooling to form new outside longerons for our PT-22 aircraft.

Caption: Composite photo of the 8' longeron. Many rivets attest to the primary structure responsibility of this part.

For lack of these parts, slightly damaged aircraft frequently cannot be returned to flying condition after experiencing only moderate accident damage. These outside longerons are usually among the first parts of the airframe to require replacement, and are critical to its structural integrity. Replacements have been available only when taken from another airframe that is being permanently taken out of service. Numerous Ryan restorers, metalworkers and repair shops have attempted to make serviceable reproductions of these parts without much success. The difficulty has been in forming the front six inches of the eight-foot-long longeron. Until now, no one has been able to form this section of the part without duplicating the original Ryan tooling, which would be prohibitively expensive, considering the small market available for these parts.

Jim Miller (IRC872), has succeeded in making a roll forming tool that is able to form this area of the longeron using 2024-T3 material, which is about five percent stronger than the original 2024-0 material. The 2024-0 material required many annealing steps, and then expensive heat treatment to the 2024-T4 state, followed by a straightening operation prior to use. Jim is now confident that the part can be formed in small quantities at a price of $1,000 each or less, on completion of both the eight-foot-long tooling to form the hat section and the forming tool for the tapered rear section of the longeron.

Jim is willing to fund the remaining labor, material and development for these tools if members will commit to purchasing at least six sets of the formed part. As of mid-June, members have only committed to four sets, and they have not been required to put up any of their own funds to finance it. Jim advises that no funds will be due until completely formed parts are ready to ship, about six months after the remaining tools are started. Jim has invested well over six months of intense development effort in this project to reach his current ability to successfully form the most difficult portion of the longerons. He will invest no further work into this project without the commitment of supporters to purchase the remaining two sets of formed parts.

The parts will be supplied as formed aluminum material, which can be completed by trimming to width and drilling the 110+ holes that make the formed part into a useable left hand or right hand aircraft part. As this is additional work by the owner or repair shop, the final part will be an ?owner-supplied part,? useable under current FAA rules. A copy of the original Ryan drawing of the longeron will also be supplied, courtesy of the San Diego Aerospace Museum, showing the location and size of all the holes.

This is a challenge to members?Do you really want to preserve these aircraft enough to support this project, even if you do not have an immediate need for these parts? Don?t let this effort be wasted due to lack of interest!

Give Jim a call at 816.358.5086 if you feel you can help.

Jim Miller (IRC872), at 70, is still an active supporter of the homebuilding movement (he has been since 1954). His hobby was kindled by a 1943 war bond drive, when he got a ten-minute ride in a Civil Air Patrol Taylorcraft for buying a war bond with his paper route savings. He has always been concerned with making aviation affordable for the little guy on a fixed budget.

He has built or restored twenty-eight aircraft since 1953. They have encompassed wood, tube and fabric, all metal and composite construction techniques. He is currently restoring a 1937 Ryan STA. One project, an all wood Taylor Titch, was on the cover of the March 1974 issue of Sport Aviation after taking workmanship awards at Oshkosh ?72 and ?73. He has been a homebuilt judge at Oshkosh for thirty years, and a tech counselor since 1966. He was a volunteer at the first Rockford Fly-In, and has remained one since. His latest effort being successful in getting himself appointed as an amateur built DAR in January of this year.

He retired as a Senior Professional Engineer in 1994. He had a colorful engineering career that encompassed the manufacture of Ford?s two-passenger T-Bird and retractable hardtop in the 1950s. His career also included manufacturing nuclear weapons components, power mowers, electrical tools and cooling towers. He was involved with nuclear power plant design and construction just prior to his retirement.

He has written numerous ?how-to? articles published in Sport Aviation and Experimenter Magazines, with more in the works. Aviation has always been his hobby. He has, for the most part, kept it barely self-supporting. But, as he says, ?It has been my most rewarding endeavor!?

By Wes Schmid, Sport Aviation Association magazine, To Fly, Summer 2004.

[BANJO]

Jim: Where do you stand on the longeron project? Do you have the minimum order? <bahern@bellsouth.net>