GPS IIF-2 Launch Pending

There was speculation about a possible delay to troubleshoot some sort
of electrical problem within the spacecraft but GPS IIF-2 is still
scheduled for launch atop a Delta IV rocket on 7/14/2011. The
launch window is now 0649-0708Z.

--- CHAS

Hi Chas,

Thanks for the info. However knowing which PRN will be used for IIF-2
(SVN63 ?), and its orbital position, is a bit more important.
Even a 2 week delay launching IIF-2 isn't likely to have any
significant impact to the constellation status.
But which PRN is used and what orbital slot the upcoming launch will
take can make far more important effect on the constellation,
specially during upcoming planned satellite delta Vs, Cs clock MX and
other planned GPS satellites downtimes. Hopefully if they take away
PRN30 for IIF-2, SVN30 can be reassigned PRN1 and keep serving the
constellation.

Regards,

Marcelo Pacheco

Marcelo,

Apparently, SVN63 (GPS IIF-2) is going to the D Plane. I'm still
thinking it will replace SVN24 (PRN24) there. According to the
National Geospatial-Intelligence Agency (NGA) GPS Division, it will
send PRN01 from slot D2:

http://earth-info.nga.mil/GandG/sathtml/satinfo.html


I'm not sure if the ultimate PRN assignment for GPS IIF is important.
Speculating about possible options:

a) Turn off residual SVN35 currently using PRN01 (NANU 2011043) and
set GPS IIF-2 to PRN01
b) Decommission SVN24 (PRN24) and set GPS IIF-2 to PRN24
c) If SVN30 (PRN30) is broken, turn it off and set GPS IIF-2 to PRN30

Of course appropriate adjustments in the operational advisory will be
required. The system operators will juggle PRNs to accommodate a
maximum number of satellites restricted by master control limitations.

According to NGA, the first GPS IIF satellite came on the air
utilizing its Cesium atomic standard. Later its clock was switched to
the current Rubidium clock. The system operators might do that for
the new satellite.

--- CHAS

On 2011-07-07 10:55 , HIPAR wrote:

If ve vant you to know, ve vill tell you.

--
gmail originated posts filtered due to spam.

wrote:
0
o

Launch delayed. T - 9hours and counting (hopefully). Time now
18:45GMT, beginning launch window at 06:45GMT.

Marcelo Pacheco