View Full Version : Cockpit equipement redundancy,

15th Feb 2002, 21:24

Can anyone shed anylight on systems [nav aids, radar, auto pilot, fligt management systems instruments etc.] where redundancy has proven to be effective rather than just a means of satisfying the regulators?


16th Feb 2002, 03:11
This is a wind up ?

16th Feb 2002, 03:16
sorry if you cant take that question seriously.

I am looking for comparisons of redundant systems, to compare to ATC, for my final year project of my Degree.

so can anyone help?

21st Feb 2002, 00:25
Tarpon. .Your email is not working. Contact [email protected]

21st Feb 2002, 05:52
"I am looking for comparisons of redundant systems, to compare to ATC, for my final year project of my Degree."

Sorry Tarpon, John Tullamarine is not the only one having difficulties understanding where you are coming from. Are you under the impression that modern airplane systems don't break down with any regularity?

Even if they didn't break down, redundant systems are required for the normal operation. For example, on modern aircraft, 3 or more IRS systems are used continuously for navigation: IRS's have measurable drift rates and instead of an autopilot using only the position of one IRS as a reference, it uses an "average" position of, say, all three, which should offset some of the drift.

When an aircraft makes an Autolanding, redundant IRS, ILS, Radio Altimeter, Autopilot computers and servo systems are brought into play, operating simulataneously. The signals are compared and oddball values are rejected... or out-muscled.

With things like VHF Comm, there are often three systems. These are generally reliable... However, one of these systems may be in use by the ACARS system (continuously). Therefore, there are really only two systems normally available for voice ops.

Redundant systems are also useful for improving system reliability. If you alternate from one system to another, the aircraft is safer: If you use the same system for every flight, it is likely that that system will break down first... and selecting a backup system which may have been dormant for months or even years, is asking for more trouble (Leave a new car in storage for a year and see how many problems you have when you go to use it <img src="wink.gif" border="0"> ).

Anyway, hope there's some food for thought here?

Rgds.. .Q.