SonexBuilders.net

One thing I noticed from various completed B-model Sonex is the lack of brake lever at the passenger side. If you are using the aircraft for training purpose and giving left seat experience for new builders. It would be nice to have full access to all controls from the right side, including brake.

With B-model sonex (with center stick), the brake lever has to be the opposite hand holding the stick. The brake master cylinder is located on the pilot side wing attach angle at seat level instead of floor level. I wonder if anyone have some ideas on how to add another lever at the passenger side that has mechanical connection to the pilot side?

I am thinking of adding a torsion tube attached to the floor pan in front of the wingbox. with lever on each end. Then add a link from the left lever to the master cylinder arm. I have seen similar mechanism on A-model dual-stick sonex from a builder who wanted put the lever in the middle. I am thinking of using 6061 tube as torsion tube and weld a lever at the end of the tube. But I am concerned if 6061 can handle shear load or twist required to provide braking force to the master cylinder.

if your going with hydraulic brakes you could just T off the hose and run another activation lever on the other side. the other option might be to place a hydraulic brake lever on the center stick, like a hand brake on a bicycle.

I dont know if one could run master cylinder in parallel. They do sell remote master cylinder without reservoir that you can run in series with the primary master cylinder. It could be a safer bet than dealing with designing lever mechanism and potentially could be lighter as well.

Master cylinders are run in series on almost all small planes having brakes on both left and right rudder pedals. Matco has diagrams on their website showing the plumbing. A normal master cylinder is “flow through” when not depressed.

See: https://static.veracart.com/matco/item_ ... ument1.pdf

This is the reason (having brake control from either side) why I will be using feet operated brakes in my XENOS-B

Carlos