Here I'll put a collection of mechanical information/ideas regarding my

Sonex Plansbuild Airplane Project




Kart seat-pan:

This type of seat may be just right for the dual-stick setup. The seat-pan is available in carbon-fibre and covered with thin deer-leather (and is probably still less heavy than the Sonex sheet aluminum pieces).



Drills, Hole Sizes, Hole diameter Limits, June 17th, 2001

(for rivets used at Sonex, taken from AC43-13)

 Rivet  Drill Size  Min. Hole Diam. Max. Hole Diam.

 AD4 =

1/8" = 3.18mm

#30 = 3.25mm  0.125" = 3.18mm  0.135" = 3.43mm

 AD5 =

5/32" = 3.97mm

 #21 = 4.04mm

#20 = 4.09mm

 0.156" = 3.96mm  0.171" = 4.34mm

  AD6 =

3/16" = 4.76mm

 #11 = 4.85mm

#10 = 4.93mm

 0.187" = 4.75mm  0.202" = 5.13mm



Seats, June 15th, 2001

I researched the racing cart scene recently, particularily for brake/rim products. Besides of this interesting products I found also very lightweight carbonfibre seats. I tend to install two of these instead if the crude Sonex sheet metal seats.



Bushings, March 28th, 2001

For support of the elevator pushrod the Sonex' plans show some cheap 'snap-in' plastic bushings. From my point of view this will cause unnecessary friction in the pitch control system. Friction counteracts the airodynamic counter-forces which may lead to unpleasant flight characteristics. So what I'll do is to install low-friction linear bearings

Igus is a German supplier for such quality plastic bushings (iglidur)