ARGOS O/C 37, NOAA

Prepared by: M.Fitzmaurice

Date: June 11 -- 13, 2003

# [Agenda Items D-1: Status of spacecraft: NOAA-11 to NOAA 17]{.underline}

[Review of Spacecraft Current On-orbit Performance]{.underline}

[NOAA-17, 16, 15, 14, 12, and 11]{.underline}

**[EXECUTIVE SUMMARY]{.underline}**

[NOAA\'s on-orbit operational satellite constellation currently consists
of the NOAA-17, 16, 15, 14, 12, and 11 spacecraft. NOAA-17 was launched
June 24, 2002 and replaced NOAA-15 as the operational morning spacecraft
(albeit in a mid-morning versus N15\'s early morning orbit). After an
extensive series of on-orbit verification and functional tests, all
NOAA-17 product systems were deemed operational in October 2002. NOAA-16
was launched on September 21, 2000 and replaced NOAA-14 as the primary
afternoon satellite. Although NOAA-16\'s product systems are functioning
to nearly 100 percent capacity, on-orbit anomalies prevent the satellite
from operating at peak performance and from providing all user needs.
Specific anomalies include 1) degraded performance of the Automatic
Picture Transmission (APT) Very High Frequency (VHF) transmitter and one
of three L-Band transmitters (1707 MHz), and 2) reduction in signal
strength of the 243 Mhz channel on the Search and Rescue Repeater (SARR)
instrument. NOAA-15 has suffered significant bus and instrument
anomalies during its 4 year on-orbit period as the primary operational
morning satellite. Launched May 13, 1998, the satellite has lost
two-thirds of its L-Band downlink capability due to antennas failures.
The only downlinks available are at 1702.5 and 2247.5 MHz and the latter
is the dedicated emergency S-Band downlink. In addition, two of
NOAA-15\'s primary instruments, the Advanced Very High Resolution
Radiometer (AVHRR) and HIRS, have behaved in an erratic fashion since
June 2000. However, their performance has stabilized with occasionally
minor perturbations in scanner and filter wheel performance
respectively. Their operation has been stable enough recently to be
re-integrated into the operational product systems. NOAA-14 has drifted
to an almost 7:00 pm (local) equator crossing node (ECN). It is now
considered a backup satellite but, due to orbit drift (it is orbiting in
the same plane as N15), its environmental products are a lower priority
than N15 from an operations viewpoint. NOAA-12 is currently in standby
mode and transmitting APT, HRPT, and STIP (low rate data which includes
Argos DCS) once per day. NOAA-11 is also a standby satellite producing
stored and real-time low rate data (TIP) to both NOAA CDA\'s and
providing 24 hour dataset (on a delayed basis) support for Argos and
Search and Rescue (S&R) programs including ozone monitoring. Current
planning has NOAA-11 being deactivated before the launch of NOAA N in
2004.]{.underline}

**[ACTION REQUIRED]{.underline}**

[No specific action is required.]{.underline}

Agenda Item: D1

Review of Spacecraft Current On-orbit Performance

NOAA-17, 16, 15, 14, 12, and 11

**[NOAA-17]{.underline}**[ ]{.underline}

[The NOAA‑17 satellite was successfully launched at 11:22am PDT/2:22pm
EDT from Vandenberg Air Force Base on Monday June 24, 2002. The orbital
altitude is approximately 860 km. NOAA-17 began fully operating as the
primary morning polar satellite on March 20, 2003. It replaced NOAA-15
as the primary operational afternoon ascending satellite. The current
equator crossing time for this satellite is 2213 local ascending node
(mid-morning descending). The Satellite Operations and Control Center
(SOCC) in Suitland, Maryland currently retrieves all (24 hour) Data
Collection System (DCS) instrument data via Global Area Coverage (GAC)
playbacks during 10-12 real-time passes over their Fairbanks, Alaska and
Wallops Island, Virginia Command and Data Acquisition (CDA) Stations
each day. The data retrieval timeliness for N17 is routine for a primary
satellite. , When conflicts with other satellite data retrieval
opportunities exists, data retrieval priority is highest (except for N16
which is equivalent and rarely in conflict due to orbit plane
differential).]{.underline}

**[Note: The DCS instrument and all of its Data Recovery Units are fully
operational and no anomalies reported.]{.underline}**

**[NOAA-16]{.underline}**[ ]{.underline}

[The NOAA‑16 satellite was successfully launched at 3:22am PDT/6:22am
EDT from Vandenberg Air Force Base on Thursday September 21, 2000. The
orbital altitude is approximately 860 km. NOAA-16 began operating as the
primary afternoon polar satellite on March 20, 2001. It replaced NOAA-14
as the primary operational afternoon ascending satellite. The current
equator crossing time for this satellite is 1401 local ascending node.
The SOCC is currently retrieving all (24 hour) DCS instrument data via
10-12 real-time GAC playback opportunities each day. As the primary
afternoon satellite, when conflicts with other satellite data retrieval
opportunities exists, data retrieval priority is higher and equivalent
to N17.]{.underline}

**[Note: The DCS instrument and all of its Data Recovery Units are fully
operational and no anomalies reported.]{.underline}**

**[NOAA-15]{.underline}**

[The NOAA-15 satellite was successfully launched at 8:52 PDT/11:52 EDT
from Vandenberg AFB on May 13, 1998. NOAA-15 became operational on
October 26, 1998 and began operating as the primary morning polar
satellite on December 14, 1998. NOAA-15 replaced NOAA-12 as the primary
operational morning descending satellite. With the launch of N17 in June
2002, N15 became a secondary satellite in October 2002. The N15 current
equator crossing time for is 0651 local descending node. This orbit
plane is currently shared by N14, which is drifting at about 5
min/month. As conflicts arise, N15 has priority over N14, but, as a
secondary morning spacecraft, all (24 hour) DCS data recovery is
accomplished using 8 satellite contacts per day retrieving GAC data.
]{.underline}

**[Note: The DCS instrument and all of its Data Recovery Units are fully
operational and no anomalies reported.]{.underline}**

[Note: In less than a month on orbit (May 1998), the high gain S-Band
antennas on NOAA-15 began to degrade in performance. Later, all three
antennas completely failed due to mechanical design flaws. A decision
was made by NOAA management to use the backup omni antennas on board the
satellite. Unfortunately, only two omni antenna downlinks were available
to perform the data playback transmissions, typically performed by the
three, high gain antennas. The omni L-Band downlink (1702.5 Mhz)
supports the real-time High Resolution Picture Transmission (HRPT, which
contains DCS data) while the omni directional S-band downlink (2247.5
MHz) is used for stored mission global data set (GAC). ]{.underline}

**[NOAA-14]{.underline}**[ ]{.underline}

[NOAA-14 was successfully launched on December 30, 1994 into an 850 km
orbit. Since NOAA-16 became operational on March 20, 2001, NOAA-14 and
has been designated as standby afternoon satellite, but, due to orbit
drift, its equator crossing time is that of a morning
satellite.]{.underline}

[With this extensive drift to an early morning orbit, degradation to
environmental products exists. NOAA-14 has drifted from its 1330 Local
orbital insertion 6.5 years ago and continues to drift at an approximate
rate of five (+5) minutes per month. The current equator crossing time
for this satellite is 1851 local ascending node. Currently, the SOCC
retrieves all (24 hour) DCS data via stored TIP playbacks via 4
real-time satellite contacts per day.]{.underline}

**[Note: The DCS instrument and all of its Data Recovery Units are fully
operational and no anomalies reported.]{.underline}[ ]{.underline}**[
]{.underline}

**[NOAA-12]{.underline}**

[NOAA-12 was launched on May 14, 1991 into an 825 km orbit. The current
equator crossing time for this satellite is 1644 local descending node
(launched into a 0732 descending orbit in 1991).]{.underline}**[
]{.underline}**[NOAA-12 is currently standby satellite. It currently
uses a \'recursive\' stored command table and is only contacted once per
day for the downlink of two orbits of stored TIP (STIP). Due to
conflicts with higher priority satellites, the two orbits of STIP (which
contain DCS data) are not a routine coverage area (i.e., the time is
dependent on when SOCC \"squeezes\" a real-time contact and which
recorder is ready for playback).]{.underline}

**[Note: The DCS system is fully operational.]{.underline}**[
]{.underline}

**[NOAA-11]{.underline}**

[NOAA-11 was launched September 24, 1988 into an 850 km orbit and became
the operational afternoon ascending spacecraft on November 9, 1988. The
satellite was placed in standby mode in April 1999.Currently it\'s
transmitting all (24 hour) DCS data via stored TIP playbacks using 4
satellite contacts per day. The current equator crossing time for this
satellite is 2254 local ascending node (launched into a 1340 orbit in
1986) which \"qualifies\" it as a mid-morning satellite and orbit drift
is 1.3 min/month.]{.underline}

**[Note: The Data Collection System (DCS) is fully operational on its
single receiver. Data Recovery Unit 4 had a low throughput, has been
turned off, and is considered failed. The three remaining DRUs are
operating normally. Analog telemetry channel 95, DCS receiver gain,
showed a 6 dB drop in gain on March 19, 1992.]{.underline}**

[Current status of all NOAA satellites can be obtained with monthly
updates at:]{.underline}

**[Summary]{.underline}**

[As can be readily ascertained, NOAA\'s current constellation of 6
satellites is providing extensive coverage. The retrieval of 24 hour/day
of Argos DCS data is being accomplished on 5 of the 6 satellites using
either GAC or STIP dataset recovery. With the planned launch of NOAA N
in June 2004, the deactivation of one spacecraft is currently being
planned. Based on age, NOAA 11 is the most likely candidate, but, power
problems with N14, though currently mitigated, could alter deactivation
planning]{.underline}