Landing Gear Notes

From "Construction Notes" Falco Builders Letter, September 2003

Bob Hendry reports that "the gear on VH-SWF (N747SW) would not retract cleanly when I went out for some touch and goes. The motor kept trying to run and it would run and then not run, etc. Eventually the gear came all the way up, and it came down with no problems. On the second takeoff, it refused to retract at all, so I pulled the breaker and hand-cranked it up. I reset the breaker and the gear came down perfectly. I am going to put it up on jacks tomorrow and check for end-lan, etc. But it sounds like I may be having the screwjack wear issue that the service bulletin talked about."

I would go very slowly and first analyze and confirm what the problem is. I doubt that it has anything to do with screwjack wear. First check for end play, but I doubt that's the problem. Then I would check the system and confirm that all of the parts work properly when hand-cranked. Then try it with the motor. Are the screwjacks properly greased?-Scoti

Brake Pads for Rosenhan Wheels and Brakes
The Rosenhan 5.30 x 6 wheels and brakes once offered for the Falco use the same brake pads that are used for the Cleveland 5:00 x 5 main landing gear. We don't have an exact part number, but if anyone can offer it, we would be happy to include it here.

Cecil Rives sent us the following.

Servicing Oleo Struts -- Frank Stricker's Method
1. Jack up wings.

2. Loosen Shrader valve.

3. Lower wings, fully collapsing the strut. Make a mark on the strut indicating the fully collapsed postion.

4. Jack up wings.

5. Use a hydraulic fluid reservoir with some sort of pump to fill the struts completely full of fluid. The strut should fully extend as fluid enters.

6. Lower wings so that the strut collapses to within one inch of the mark made in step three. Provide some means to catch excess fluid.

7. Jack up wings.

8. Close Shrader valve and inflate strut to 600 psi.

9. Lower airplane and bounce airplane up and down a few times.

10. One wing will probably be low so add air to the strut on the low wing until level with the other wing.

This same procedure can be done with struts removed from the airplane and might be less messy.

Comment: The Falco shock absorber struts have an internal metering tube which insures that you have the correct amount of fluid. This method of collapsing the strut 'within one inch' of the fully collapsed position provides one inch more fluid that was intended in the design of the strut.

The usual method that we are familiar with is:

1. Jack up the airplane.

2. Loosen the Shrader valve and remove the Shrader valve core.

3. Take a length of rubber hose that will fit tightly over the Shrader valve, push one end over the Shrader valve and put the other end of the hose in a can of hydraulic fluid.

4. Lift the wheel up to collapse the shock absorber strut completely. This will cause air to be expelled from the end of the hose in the can of hydraulic fluid.

5. Lower the wheel to fully extend the shock absorber strut. This will cause fluid to be drawn into the strut.

6. Repeat steps four and five until bubbles no longer come out of the hose in the can of hydraulic fluid.

7. Repeat step four and while the strut is fully collapsed, remove the hose from the Shrader valve.

8. Lower the landing gear.

9. Install the Shrader valve core.

10. Pump the shock absorber struts to 600 psi or enough so that the landing gear struts are fully extended with no one in the airplane.

11. Tighten the Shrader valve.