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Path: utzoo!watmath!clyde!cbosgd!ihnp4!poseidon!brent
From: brent@poseidon.UUCP (Brent P. Callaghan)
Newsgroups: net.space,net.aviation
Subject: Re: "Shadowing" geosync satellites
Message-ID: <1360@poseidon.UUCP>
Date: Mon, 16-Dec-85 09:51:31 EST
Article-I.D.: poseidon.1360
Posted: Mon Dec 16 09:51:31 1985
Date-Received: Tue, 17-Dec-85 04:28:05 EST
References: <441@brl-tgr.ARPA> <605@riccb.UUCP>, <1770@utcsri.UUCP> <6226@utzoo.UUCP>
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Xref: watmath net.space:4968 net.aviation:2265


>> Now for the key question: do you call your lawyer when a 747 flies
>> overhead?  Do you KNOW?
>
>There is at least one case on record in which a small jet's crew were
>thoroughly alarmed for a moment because their radar altimeter suddenly
>showed a much lower altitude than the barometric altimeter.  Then suddenly
>things were back to normal.  Then they realized there was a 747 a few
>thousand feet underneath, slowly pulling ahead of them...

I guess this is getting the discussion a bit off the point, 
but it reminded me of the testimony of an Air New Zealand
DC10 captain at the inquiry into the Mount Erebus disaster
in 1980:

He was giving evidence regarding the accuracy of the "AINS"
(Area Inertial Navigation System).  Air New Zealand has
a 5,000 mile route to Honolulu.  At the same time, two DC10's
would depart Auckland and Honolulu on reciprocal courses.
Several hours out over the Pacific the aircraft would pass
each other at different altitudes.

The crew on the high aircraft could see the low aircraft
pass on their radar altimeter !
-- 
				
Made in New Zealand -->		Brent Callaghan
				AT&T Information Systems, Lincroft, NJ
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