October 2018 – bzvelocity.com

Fitting Booties on MLG Legs

I purchased the aluminum “booties” from the factory, as this is an opportune time to install them. The booties are supposed to help with dissipation and spreading of the thermal load due to braking during the landing rollout. Some folks have experienced sag of their landing gear legs due to the temperature rise in the brakes during extended taxi and hard braking.

My first job was to remove the existing axle from the gear leg. This was impossible to accomplish without a hydraulic press. Once the axles were removed, the cut line on the bottom of the gear leg was marked to fit the inside shape and angle of the bootie, while replicating the position of the axle flange. The gear legs were (gulp) cut with a jigsaw – no turning back now… Then the edges and corners of the gear leg were sculpted to fit the interior shape of the bootie socket.

After reinstalling the gear legs into the fuselage and verifying that the height and angles of the axles were correct, the gear legs were glued into the booties with Velocipoxy + cabo, with a smooth fillet around the edges of the joint. After curing, the holes were drilled for the bootie through-bolts.

Titanium Firewall

I received a sheet of titanium that will become the firewall shield. I plan to put a couple of layers of fiberfrax between the titanium sheet and the fiberglass firewall bulkhead as an additional thermal barrier. This combination will buy valuable time if the worst-case engine fire should occur.

Aileron Bell Crank Supports

The factory is replacing the push-pull cable aileron linkage with a new pushrod linkage. There are now bell cranks mounted on the landing gear bulkhead that connect directly to the control torque tube that passes through the keel tunnel. These bell cranks transfer motion to two long pushrods that pass through the MLG bulkhead and the firewall, connecting directly to the aileron control surface torque tubes in the engine compartment at the trailing edge of the wings.

The mating surface on the MLG bulkhead had to be filled and leveled to make a good mounting surface for the bell crank mounting bracket. Then holes were drilled through the bulkhead for the pushrods. I now have to figure out some way to determine the position of the corresponding hole in the firewall bulkhead….