From: henry@zoo.toronto.edu (Henry Spencer)
Subject: space news from Oct 19 AW&ST
To: sci-space-news@news.arc.nasa.gov
Followup-To: sci.space
Organization: U of Toronto Zoology
Date: Mon, 23 Nov 1992 21:50:59 GMT

[First, a small correction...  In the stuff on GPS for aviation last week,
I characterized precision approaches as "bad weather", the implication
being that non-precision approaches aren't very useful.  Andy Stadler,
in mail to me, reminded me that non-precision approaches are actually
useful even in fairly bad weather.  You need to be able to see the
ground before the actual landing, but that's true of the lower categories
of precision approach too (although typically you have to see it somewhat
earlier for a safe non-precision approach).  Even non-precision approaches
via GPS would be very helpful for bad-weather operation.]

Yet another fast-mission-to-Pluto proposal:  OSC and CalTech propose flying
such a mission for NASA.  CalTech would be prime contractor and supply the
imaging gear; OSC would build the spacecraft.  It would weigh 140-150lbs
and cost $130M for a ten-year mission launched by Proton.

Second successful test firing of Hercules's SRMU (upgraded Titan IV SRB)
conducted Oct 15 at Edwards.

Goldin shuffles personnel at NASA HQ:  Marty Kress goes from chief lobbyist
to space-station policy/management deputy (freeing station director Kohrs
to worry about technical issues), Lennard Fisk goes from space science head
to NASA chief scientist (a new post), and Richard Peterson goes from head
of aeronautics and advanced technology to special assistant to Goldin.
Fisk's former office will split into two, Mission To Planet Earth and
planetary science / astrophysics; Peterson's two-part office will likewise
become two.

White House spokesman, grumbling about Truly's endorsement of Clinton for
president, accidentally reveals what most everybody had already guessed:
Truly didn't quit, he was fired.

FAA announces plans for near-term start on GPS as aviation navigation aid.
By the end of next summer, GPS approaches will be authorized for almost all
airports with non-precision approaches.  In addition, differential-GPS
Category 1 precision approaches will be established at Dallas-Ft. Worth
and at a site in Alaska within a year.  Most of the problems yet to be
sorted out are questions of procedures and certification methods rather
than technical items.  There are still a couple of technical issues,
though:  data links (for differential GPS and for air-traffic control)
and integrity monitoring.  The FAA's current line on the latter is
"smart" receivers that monitor extra satellites and can detect failures.
Three phases are planned.  First, pilots using GPS for non-precision
approaches with non-smart receivers will have to monitor existing
navigation aids too.  Second (by mid-1993), pilots with smart receivers
need not monitor the older aids but must have them available and working.
Third (schedule not set), neither airport nor aircraft would need the
older aids.

On the other hand, Britain's Defence Research Agency releases a somewhat
alarming report on the possibility of jamming of GPS, e.g. by terrorists.
A jammer radiating 1 watt of suitable noise in the GPS band incapacitated
civil GPS receivers at a distance of 22km.  50km or more would not be hard.
Military receivers often have sophisticated antennas that can "null out"
jammer signals, but civil ones don't.  Differential GPS is triply vulnerable,
since it relies on both aircraft and ground station receiving good GPS data,
and on the ground passing differential corrections to the aircraft by some
sort of data link.  Worst of all, the report observes that civil receivers
can lose accuracy fairly badly in the presence of jamming that is not
quite strong enough to blank them out entirely.

Columbia on the pad for launch Oct 22, carrying the Lageos 2 geodetic
satellite and a large set of onboard experiments (notably the Space Vision
System, part of a package of Canadian experiments flying with Canadian
astronaut Steve MacLean, which uses computerized image analysis to help
precise control of the Canadarm [known as the Remote Manipulator System
to the ignorant :-)]).  The tail end of the mission will include lowering
Columbia's orbit to 210km -- lowest ever flown by a shuttle -- to expose
some experiments to a low-altitude environment.

DFS 3, last of Germany's big Kopernikus comsats, launched Oct 12 by Delta.

Arianespace is asking launch insurers to begin distinguishing between
launcher types, i.e. recognizing Ariane's reliability record and giving
Ariane launches lower insurance premiums.  Insurers observe that they
still have to look at failures of the satellites themselves, and also
that "Arianespace will have to accept that when things are going well,
it will have to pay for the misfortune of others".

Next Ariane launch delayed an unspecified amount due to last-minute
modifications to the Galaxy 7 comsat it will carry.

US government and industry attempt to save something out of the rubble
of NLS.  In particular, an effort is being made to keep some work going
on engine development, although teams will be cut back as funding shuts
down.

Thiokol proposes its Castor 120 as a large strap-on for any new-NLS
project.  The Castor 120 is an improved version of Thiokol's MX first
stage, being developed as a private venture.

Arianespace studies offering package deals to low-orbit-comsat systems,
with mass launches on Ariane and replenishment via a smaller launcher.
The choice of smaller launcher is not clear, partly because different
low-orbit-comsat schemes vary so much in satellite mass and orbit.
(Arianespace historically has been on good terms with OSC, mind you,
including having a joint marketing agreement for a while... although
it was not renewed because the small-satellite market did not develop
quickly in Europe.)
-- 
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  henry@zoo.toronto.edu  utzoo!henry
Newsgroups: sci.space.news