Return-Path: Received: from YCC.COM ([204.155.150.41]) by truman.olsusa.com (Post.Office MTA v3.1.2 release (PO203-101c) ID# 0-44819U2500L250S0) with SMTP id AAA11503 for ; Thu, 19 Nov 1998 22:27:39 -0500 Received: from YccPrimaryDomain-Message_Server by YCC.COM with Novell_GroupWise; Thu, 19 Nov 1998 21:30:42 -0600 Message-Id: Date: Thu, 19 Nov 1998 21:30:07 -0600 From: "Bill Gradwohl" To: lancair.list@olsusa.com Subject: Theft Protection Mime-Version: 1.0 Content-Disposition: inline X-Mailing-List: lancair.list@olsusa.com <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> I hope to spend some time flying outside the US, and was wondering about theft protection measures for when the plane is sitting in less than ideal surroundings. What I had in mind was something to make the plane unuseable unless you knew the "secret" to flying it. Any lock can be picked, including the door and master switch when the prize is worth enough. My background forces me to come up with electrical ideas. I was hoping others would come up with mechanical suggestions to cripple systems that aren't obvious. i.e. hydraulic gadget to lock the brakes, canopy lock alteration to prevent closing without a key, gadget to lock the nose wheel off center, etc. I had one idea which involves a minor electrical modification that is absolutely safe when I fly the plane, but absolutely unsafe or totally uncooperative (depending on wiring) when someone else attempts to move it under its own power. I took the idea from a "wrap plug" used in the computer industry and the valet keys that some cars are equipped with. Wires always go between two points. My idea is to take several wires from critical systems that go from various points (A to B, C to D, E to F, etc) and run them with a slight modification as follows: A to y, y to z, z to B; C to w, w to x, x to D, etc. Electrically this produces the same result as the original wiring and therefore is absolutely safe. The "secret" to the scheme however involves the intermediate y, z; w, x; etc connections. By using a multi pin MIL connector to hold these y,z; w,x; etc points, one could create various wiring alterations simply by plugging in an appropriately wired plug. One plug would have the correct wiring diagram. It is my "key" to the electrical system in the plane. I put it in my pocket when I leave it. Another plug would be wired in such a way so that critical electrical systems either didn't work, or worked to the detriment of the thief. One could easily make sure that fuel transfer pumps were inoperative, the ELT was tripped when the gear came up, or any number of other imaginative pranks to make stealing the plane terribly difficult. Just leaving the MIL plug with no connector in it would cripple critical systems (open circuit) and make the plane unfriendly to steal. In essence, it would be like rewiring the switches on the panel to perform functions completely different than their markings would suggest. All it takes is one or more MIL plugs, some wire, and some soldering time. I think it meets the KISS test, and if someone wanted redundancy, it could be wired with two MIL connectors in parallel where either would be enough to complete the circuits under normal conditions. My arrangement would be however I decided to wire it up, and someone else's would be completely different. No two systems would be alike, so it would be impossible (impractical) for someone to try to figure out how to hot wire the plane. Can someone come up with some mechanical gizmos? Bill Gradwohl IV-P Builder N858B