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Old 30th Jul 2011, 05:23
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JD-EE
 
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Originally Posted by takata
Having a camera showing all the displays and crew actions (postions/attitudes) would be very helpful rather than having to derive something from recorded data which doesn't give any hint about what can NOT be derived. (e.g. was the PNF reading silently the documentation? was he scanning the displays? looking at the PF actions? did they exchange meaningful regards?)
That may require just a whole lot of large disk space for fully readable displays from about ceiling height mid console. Decent HD width video requires about 100 megabits per second or more. Poor quality is about 13 megabits/second. Displays may be visible and gross features may be readable. YouTube video tends to be under 6 megabits/second even for 1080 resolution. So you can figure for yourself about readability with a vibrating cockpit. (That will make compression harder and video readability worse.)

8 megabits/second is a megabyte per second. One hour is 3.6 gigabytes. This is within the size limits for well established solid state disk technology such as could be repackaged into a Honeywell box with modified interfacing. Getting the signal back to the position in the tail will require a new wire, probably using Ethernet, for the data to be store. If Ethernet is used well established backup disk software can be repurposed.

They might be able to get this working in a few months and certified in a couple years. It would be a good idea. And I'd use a larger disk and perhaps 1/2 hour recording time before old is overwritten. Then higher resolution for more readability could be applied. With a 100 gigabyte solid state disk they could record three or four channels at quite respectable resolutions. They might need to be using gigabit Ethernet or even a pair of gigabit Ethernet connections to pass all the data. So four or more new cables might be needed to get the data back to the recorders. That's probably the most difficult to sell part of the concept.
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