/usr/share/savi/data/tundra.tcl is in savi 1.4.6-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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# * THEORETICAL CONSTELLATIONS
# *
# * Tundra high-latitude coverage - compare with similar Soviet Molnya.
# *
# * Highly-elliptical orbits useful near apogee.
# *
# * Two satellites in separate orbits are necessary for full,
# * continuous coverage of the chosen point.
# *
# * Information from 'Satellite Communication Systems', Maral and
# * Bousquet, 2nd/3rd edition, chapter 7; values are set to match
# * Figure 7.13.
#
# this script for SaVi by Lloyd Wood (lloydwood@users.sourceforge.net)
# http://www.ee.surrey.ac.uk/Personal/L.Wood/software/SaVi/
#
# $Id: tundra.tcl,v 1.12 2011/07/18 14:44:46 lloydwood Exp $
# setup orbital elements
# indicate longitude of slow-moving subsatellite point
# at approximate latitude of 60 degrees.
# east is positive
set apogee_longitude 50
set SATS_PER_PLANE 2
# constant semi-major axis for these orbits
set sma 42164.0
# eccentricity can vary from 0.25 to 0.4
# top loop vanishes at 0.37
set e 0.4
set perigee_altitude [expr ($sma*(1-$e)-$RADIUS_OF_EARTH)]
set apogee_altitude [expr ($sma*(1+$e)-$RADIUS_OF_EARTH)]
set a $sma
# inclination must be 63.435 (stationary apogee in northern hemisphere)
# or -63.435 (stationary apogee in southern hemisphere)
set inc 63.435
# switch sign around to ensure east is positive
set apogee_longitude -$apogee_longitude
# 270 degrees gives an optimal orbit
# to vary latitude, you need to vary omega and e.
set omega 270.0
set T_per [expr 2 * $PI * pow($a,1.5) / sqrt($MU)]
# zero is 90 degrees west
set offset_longitude 90
set apogee_longitude [expr ($apogee_longitude-$offset_longitude)]
# effective limit of coverage
set coverage_angle 5.0
satellites GV_BEGIN
for {set i 0} {$i < $SATS_PER_PLANE} {incr i} {
set Omega [expr $i*180-$apogee_longitude]
set T [expr $T_per * $i / $SATS_PER_PLANE ]
satellites LOAD $a $e $inc $Omega $omega $T "Tundra-$i"
}
satellites GV_END
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