The landing gear lever is mounted to the lower left cock-pit sidewall and is operated from the down position by first pulling it sideways out of a notch or detent and then pulling or ro-tating it to the up position and sliding it sideways into the up lock notch. This lever actuates the down limit switch when in the down notch, and the up limit switch when in the up notch. These switches operate the hydraulic pump in one direction to raise the gear, and in the reverse direction to lower the gear.
This system was simple, but it had one problem. When the gear hits the limit switch actuator lever, it slides across it rather than hitting it straight on. This sliding action had the poten-tial of bending or, as happened in this case, even breaking the limit switch-actuating lever. Once the limit switch-actuating lever was broken, the hydraulic pump would not run in the down direction. While the pump would not run, the gear would still fall due to the force of gravity but with consider-able resistance from the hydraulic pump, fluids, etc. It would take a con-siderable amount of time for the gear to fall under these conditions and would require sideslipping at relatively high speeds in order to force the gear into the over-center locked position. John Williams was aware of this short-coming and had redesigned the lever for production airplanes but had not changed it on the prototype.
The new lever works much the same way, but when the lever hits the limit switch, it pushes it straight in without any sideways motion. This minimizes the potential for damaging the limit switch. Production planes, as well as the prototype, are now equipped with a dump valve that releases all hydraulic pressure and allows the gear to fall into the down and locked position more readily.
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