Re: Boeing landing procedures

From: (Ted Gallop)
Organization: Curtin University of Technology
Date:         22 Apr 95 03:53:51 
References:   1
Followups:    1 2
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In article <airliners.1995.437@ohare.Chicago.COM> "Steven J. Leighton" <> writes:

>I am currently undertaking a study into the accuracy of aircraft
>landing systems. As part of the study ILS, MLS and DGPS data recorded
>on board a 767 is being investigated.

>I have been led to believe that for the final 200 feet before
>touchdown Boeing aircraft use the INS system for landing as opposed
>to ILS alone. Could someone please clarify if this is truly the case.

No they don't.

On the latest systems, the autopilot/autothrottle and INS are integrated to
such an extent that when you are using one you can be considered to be using
both. However, the autopilots (all 3 of them) would be engaged and locked on
to the ILS if an autoland was being considered.

Of course, not all ILS ground installations are of sufficient
integrity to permit autolands in 'real' situations (as against fine weather