Newsgroups: sci.aeronautics.airliners
Path: news
From: hfunk@src.honeywell.com (Harry Funk)
Subject: Re: New Scientist article
X-Submission-Date: Thu, 10 Dec 1992 15:13:01 GMT
References: <airliners.1992.105@ohare.Chicago.COM>
 <airliners.1992.116@ohare.Chicago.COM>
Message-ID: <airliners.1992.135@ohare.Chicago.COM>
Approved: kls@ohare.Chicago.COM
Reply-To: hfunk@src.honeywell.com (Harry Funk)
Organization: Honeywell Systems & Research Center
Sender: kls@ohare.Chicago.COM
X-Submission-Message-Id: <1992Dec10.151301.10339@src.honeywell.com>
Date: 10 Dec 92 16:07:15 PST


In article <airliners.1992.116@ohare.Chicago.COM> dmarble@magnus.acs.ohio-state.edu (Duane F Marble) writes:
>A small point with respect to the material quoted from the New
>Scientist: Global Positioning System (GPS) birds do not "observe"
>anything, they just permit a ground based unit to compute it's
>location.

My guess is that he was referring to Automatic Dependent Surveillance (ADS)
systems based on SATCOM, which has even less to to with GPS/Glonass birds.

The planes [would] communicate their positions by means of a satellite link
to a ground-based tracking/control system.  United currently has a few
747-400's that are so equipped.  The major benefit envisioned is for
oceanic routes, where the fixed spacing (slots) system currently used
results in suboptimal tracks for a number of users of the system.  ADS is
the successor to the Oceanic Display and Planning System (ODAPS), which I
think is currently installed at the Oakland and NY Air Route Traffic
Control Centers (ARTCCs).  
--
Harry A. Funk     Principal Research Scientist        Voice: (612)-782-7396
Honeywell Systems and Research Center             FAX:       (612)-782-7438
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