It looks very good. How does the design compare with automotive drilled and slotted rotors? Ted Noel
Just a note of caution here, from experience with drilled rotor in the automotive world: The drilling of rotors is intended to allow liquids and vapors emitted by the pad material to escape instead of being trapped between the pad and the rotor. This allows the friction coefficient to remain high at higher temperatures than could otherwise be used. The drill pattern has to be carefully done as the holes will increase the thermally-induced stress in the rotor and the drill pattern is usually designed to expose every part of the pad to a hole at least once per revolution. One shouldn't underestimate the stresses in the rotor - that's why the rotors tend to warp as they exceeded the yield stress at some spot on the rotor. Also, sometimes you will see spiral-oriented slots on the surface of the rotor and these have the same function as holes - nNo need to add slots and holes. Race cars generally use "soft" organic pads that wear fast, but keep a consistent coefficient. This fast wear means that there is a lot of pad material to get rid of, leading the need for the holes or slots. These organic pads also conduct heat less than metallic pads, keeping the brake fluid cooler. For an aircraft that only has to stop once, the best approach might be to use metallic or semi-met pad material and not drill the rotors. The pad material allows operation at higher temperatures, but will wear the rotor faster. The brake fluid isn't in danger of boiling as the brake will cool before the caliper gets that hot. Just don't do repetitive high-energy stops (like during high-speed taxi tests).
Gary Casey |