The American Bonanza Society Air Safety Foundation is offering cash prizes to those who can come up with a solution to the Beechcraft V-Tail Bonanza’s ruddervator problem.
The problem
According to society officials, the grade of magnesium used for ruddervator (pitch/yaw) flight control skinning in Beech Model 35 (V-tail) Bonanzas is very costly and difficult to source. Magnesium corrodes rapidly when exposed to the atmosphere, and the need to reskin ruddervators is fairly common. However, there are no approved repairs to even very light damage or corrosion to magnesium ruddervators except for complete control surface reskin.

“Because of their unique characteristics ruddervators require precise balance and aerodynamic flutter properties,” officials explained. “Ruddervators must be kept comparatively light to avoid excessive aircraft tail-heaviness.
The challenge
Engineer a replacement skin or complete replacement control surface that meets balance and flutter protection requirements, that does not adversely affect overall aircraft weight and balance, and that uses readily available materials, such as more readily sourced magnesium, aircraft aluminum, composite and/or modern, long-life fabric covering, at costs comparable to existing control reskin or replacement, while addressing any issue of dissimilar materials interaction.
The ABS Air Safety Foundation Manuel Maciel Aviation Research Prize is designed to spur research and certification of alternative to current ruddervator skinning techniques. The prize is funded by the Manuel Maciel bequest for aviation safety research. Maximum combined prize payout is $200,000.
The prizes
The ABS/ASF Manny Maciel Structures Engineering Prize
$20,000 each to the first five teams from an academic or vocational aerospace engineering or aircraft structures repair program, private enterprise, or engineers working privately or together, that:
- Designs a replacement ruddervator skin or control surface replacement meeting all FAA control surface balance and flutter control criteria for at least one iteration of ruddervator design (the design varies in models produced in 1947-1949, 1950-1963, and 1964-1982), across that airplane’s entire existing flight envelope, and validates that design using industry-acceptable practices;
- Constructs and tests a full-scale ruddervator and/or Finite Element Model confirming the design using criteria in (1) above and using industry-acceptable testing practices;
- Successfully addresses any issue of dissimilar materials interaction;
- Submits to the ABS Air Safety Foundation a detailed engineering report, including the time and cost to complete FAA certification, and an estimated cost of the repair or replacement of one control surface assuming certification is obtained;
- Passes a peer review process as determined by a panel of industry experts in consultation with the ABS Air Safety Foundation; and
- Makes the final report and all results available in open source documents for free use by any firms pursuing FAA Supplemental Type Certificate approval of the design for commercial application.
Individuals or teams using open source information published by others who have previously earned the Structures Engineering Prize are not eligible for the prize without demonstrating through the peer review process that their design is substantially different, easier to certify or is or significantly less expensive to produce than other entries, society officials note.
Deadline for submission of entries for the Structures Engineering Prizes is June 1, 2023.
The ABS/ASF Manny Maciel Ruddervator STC Prize
One prize of $100,000 to the first commercial enterprise that earns FAA STC approval for ruddervator reskin or replacement valid for all models of Beech Model 35 Bonanza across the airplane’s existing flight envelope without adversely restricting the airplane’s current loading envelope. The winner must have available for purchase at least five complete modifications kits or finished control surface units at a price no more than 20% greater than traditional magnesium skin replacement or complete control surface replacement, based on December 2018 prices.
Deadline for submission of entries for the STC Prize is Dec. 31, 2025.
Balsa and Topflite Monokote is what I use.
So what is the official December 2018 prices?
“at a price no more than 20% greater than traditional magnesium skin replacement or complete control surface replacement, based on December 2018 prices.”
3d print the thing solid using a structural infill to save weight. Ultum material is already approved to use in flight by the faa.
+1 on carbon. Do I get my 500 $ share for precisizing Kevlar?
I’m not part of a teamp51Don’t have the where with all to design or manufacture and test a part to FAA standards.
But an all carbon fiber part should be lighter, stronger and impervious to corrosion.
Just send me $1,000 if my idea works.
typo after team teamp51 was a typing error
Sounds like a natural for Titanium alloy…