Hi There! -----Original Message----- From: Sean H. Breheny To: PICLIST@MITVMA.MIT.EDU Date: 27 July 1999 06:41 Subject: Re: [OT] Re: Car LED lighting system; PIC filament monitoring >Ok, I know that I don't seem to get things straight when I watch those TV >programs about crashes , but here goes another recollection: > >If they haven't implemented it already on some aircraft, the idea is >definately at least in the proto stage to do exactly what you say,Wagner. >They are planning on a two-way data link that transmits weather info, air >traffic control info, aircraft flight/engine instrument readings,etc. IMHO, The system is already implemented and uses the VHF communications rx/tx, It is called ACARS. this is only one data transfer system. The ATC system uses a new mode called the Mode S, this is used for the TCAS (Transport Collision Avoidance System) system, can also be used as a digital data transfer system. Then there is the new SATCOM system wich replaces the old HF communication system, which can also be used as a data transfer system. They are busy building centres all over the world to capture the data and send it from there to the airlines, and manufacturing places. >I don't think it would be a bad idea to have an "external control" >switch,which you could turn on and it would allow people on the ground to >set the autopilot,etc. Just in case of the "Pilot and Copilot are dead" >situation,which the movies love ;-) > >Also, I don't know about the IrDa,but they DO use digital recording >methods,and have MANY sensors, recording at a lot faster than once per second. > >In fact, they use voice recorder ICs for the CVR. Even the tape which they >are no longer using on new models, was digital,unless you go way far back. >This last part I learned from the link which was recently posted here, > This is true that the old tape models are being replaced by flash memory. There is not only one "Black box" onboard an aircraft but two. One is called the Cockpit Voice Recorder and the other the Data Recorder. Everybody knows what the CVR does, the Data Recorder Records essential Data from various sensors which is the most important. There is also a big difference between the old aircraft which used the analog standard and the new aircraft which uses the ARINC 419 spec., more sensors can be recorded and at a quicker rate. This is the only two units used for official enquiery int an accident but there is another data aquasitioning system which the airlines use for general performance data, this system is capable to record more than just half an hours data and much more sensors. To give an example, the tire presure of each tire is recorded and the duration of each Radio System is recorded plus much more, If memory serves correct over 2000 sensors lives on the aircraft but not all is recorded, this depends on the ailines. I can try and get more technical info if anybody is interested. I will however not be available for three weeks becuase i am going on vacation to CANADA >http://www.airdisaster.com > >Sean Zack E-Mail: spazzman@iname.com One regrets more the things that you did not do than the things you did do.