Friday, September 12, 2008

Stall Warning Microswitch - Section 16







I spent today completing the steps in Section 16, Stall Warning, almost..... All went well assembling the stall warning switch. Because of the problems associated with the washers, as mentioned in my previous post, I elected to place 7 AN960-4 washers (I measured the one's sent to me at 0.023") between the outboard face of VA-195A and the micro-switch. This gave me a build-up of 0.161" compared to a buildup of 0.160" if the AN960-4 washers were per the MIL spec. I placed 3 of of the 0.023" AN960-4 washers between the micro-switch and the VA-195B keeper plate. With this arrangement the stall warning vane did not bind. After I installed the wing skin to check alignment, the vane was centered in the slot in the wing skin. (All of this was approved by Van's via a phone conversation.) Then continued to build the terminal brackets. The terminal brackets provide the contacts necessary to connect the electrical connections between the wings and the electronics in the fuselage. Installed the stall waring micro-switch and then attached the W-1202-L mid-skin to check alignment. During this step, follow the instructions and only cleco where the drawing specify. Cleco'ing as such, allows one to bend the upper skin up a bit, allowing access to the adjustment screws on the stall warning sub-assembly. After this learning process, I was successfully able to adjust the switch per the specifications. Had a problem assembling the terminal bracket. Van does not supply enough MS21042-08 nuts. I had two of the nuts, and need at least 1 more. Anyone noticed this?? Called them, spoke to Tom and will receive them next week. Lucky that this will not influence any further progress. Notice the high tech string through all of the nose ribs. The plans call for the installation of the string, most likely for wingtip lights, etc. The terminal brackets also have the connections that will allow for the future additions.

Time - 5 hours