Re: 7x7-EFIS question

Date:         31 Dec 99 02:09:30 
From:         Ron Parsons <jrp59@gte.net>
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In article <airliners.1999.1255@ohare.Chicago.COM>, ice
<iceboy@cix.co.uk> wrote:

>How well does the 757/767 conform to the ideal descent profile with
>VNAV engaged with strong tail winds? I have heard FLCH is a better
>tool in such circumstances?

It depends on the accuracy of your descent winds. When they are uplinked
just before descent with an accurate profile the profile works out
pretty well.

However, you do have to know what you are asking the aircraft to do, for
example a 757 descending into San Jose, Cost Rico and using the MEA's as
at or above limits needs about 1/4 speedbrake and throttles idle to get
down.

>Also do you HDG SEL onto the LOC, or LNAV? I assume because of
>Map Shift you HDG SEL..

Old instructors whose mothers were scared as children by midnight tales
of the dreaded map shift always teach HDG SEL, but the aircraft is going
to stay locked on heading with no anticipation in that mode until the
LOC needle is way, way in. Not good on parallel runway intercepts. Most
days at DFW, a HDG SEL intercept on a visual day will see the aircraft
cross the spine road before it gets back on its side of the airport.

However an LNAV intercept at a high angle will begin to turn before
there is any LOC movement at all.

--
Ron