RE: Titan IV B-30 Tracking stations

From: Ted Molczan (molczan@rogers.com)
Date: Thu Apr 28 2005 - 08:59:16 EDT

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    Jim Holland wrote:
    
    > In reference to the launching of the payload on Titan IV 
    > B-30, I am curious if anyone has any informaytion on tracking 
    > procedures for this mission. In the local news here there 
    > have been several articles pertaining to a "mystery ship" 
    > docked in the harbor in Portland Maine. The picture of the 
    > ship shows what appears to be 2 radomes, fore and aft. 
    > According to the articles the ship is being rented by 
    > Lockhead Martin. Since Titan IV B-30 has a trajectory which 
    > brings it along the U.S East Coast it does raise some speculation.
    
    Here are the original news reports from the on this matter:
    
    http://pressherald.mainetoday.com/news/local/050423ship.shtml
    
    http://pressherald.mainetoday.com/news/local/050427mysteryship.shtml
    
    The news reports indicate that The Sage arrived about April 1, which was about 5
    days prior to the April 6 launch date, that had been planned for some time, so
    the timing seems about right to connect the two. 
    
    I suspect that The Sage may be used to provide tracking and/or telemetry
    support, probably to fill a gap in the existing coverage.
    
    Here is how The Sage fits geographically into the ER (Eastern Range):
    
    Wallops Island              37.9 N  75.5 W  Tracking
    
    New Boston, New Hampshire   43.0 N  71.7 W  Telemetry
    
    The Sage (Portland, Maine)  43.7 N  70.3 W  ?
    
    Argentia, Newfoundland      47.3 N  54.0 W  Tracking, Telemetry
    
    The following discussion assumes that The Sage will remain near Portland, Maine
    during the launch.
    
    Since The Sage is located near New Boston (within about 140 km), which provides
    telemetry support, it would seem that it would not have the same mission -
    unless, there are some payload-unique requirements that New Boston could readily
    meet.
    
    Depending on the altitude and ground track of the launch, perhaps The Sage is
    positioned to fill a tracking coverage gap between Wallops and Argentia, near
    the time of orbital insertion, a little over 9 minutes after launch.
    
    In particular, I find that a USA 144 type initial orbit, which would be fairly
    low at the point of orbital insertion (about 210 km), might suffer such a
    tracking gap. I posted a search elset yesterday:
    
    http://satobs.org/seesat/Apr-2005/0273.html
    
    USA 144 type
    1 71002U          05120.08650464  .00690749  00000-0  60000-3 0    08
    2 71002  63.3898 154.6699 0077500  65.0000 328.1000 16.06300000    09
    
    Wallops would see orbit insertion at about 5 deg elevation, about 1 min before
    the vehicle would pass below the horizon.
    
    Argentia would see orbit insertion at about 8 deg elevation, about 2 min after
    the vehicle would rise above the horizon.
    
    The Sage would see orbit insertion at about 33 deg elevation, just past the
    mid-way point of its pass.
    
    I do not know enough about radar to judge whether or not tracking within 5 - 10
    deg of the horizon is considered problematic.
    
    Also, I caution that my search elements can be off by several degrees in terms
    of ground track, and I have not tested the sensitivity of this analysis to that
    uncertainty.
    
    Ted Molczan
    
    
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