NASA NGSLR, Руководство по эксплуатации

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NGSLR Operations Manual Operations Requirements and Emergency Procedures
Document Number: P a g e | 9
NASA NGSLR OPS Manual (v1.0)
2.1.2 Reasons to stop tracking
Laser Ranging occurs for scheduled passes as cloud conditions and ILRS restricted tracking parameters permit.
Exceptions include the following conditions where the dome must be closed in order to protect sensitive
equipment:
1. Precipitation of any kind
2. Sustained gusts of greater than 40 mph (17.8 m/s)
3. Temperatures that are above 122° F (50° C) or below 14° F ( 10° C)*
Some missions define whether they will allow satellite tracking at a particular time. See the ILRS website for more
information on tracking restrictions at: http://ilrs.gsfc.nasa.gov
2.1.3 System Readiness
Depending upon past tracking performance (both NGSLR and LRO), a decision must be made as to whether any
system alignment procedures or checks need to be performed.
Three levels of tracking readiness can be identified for tracking operations, they include:
1. SLR tracking operations are successful in previous attempts and no changes have been made The
system is tracking successfully (with or without pointing bias), and no additional alignment checks are
needed. Attempt tracking operations.
2. Previous SLR tracking engagements have been unsuccessful for unknown reasons Attempt tracking,
noting any unusual biases, system errors, or hardware anomalies on the log sheet. Immediately stop
tracking should a safety related failure occur.
3. Maintenance, alignment, and or development work is required to bring the system up to full tracking
readiness
Tracking is not possible in this state. This may include laser or equipment replacement,
timing or star calibration issues, or equipment failure.
2.1.4 Equipment to be left running
Warning
: The following equipment should never be turned off!
GPS Time and Frequency Receiver (XL DC)
Computer Clock Sync Interface (CCSI)
Cesium Frequency Standard
Event Timer (ET) Range Gate Generator (RGG)
Constant Fraction Discriminator
The NIM Crate
Power Distribution Box
There are certain devices and equipment that should never be turned off except in the case of an emergency
such as fire, water leaking through the roof, etc. This ensures that accurate timing is maintained. All timing
sensitive equipment will have a yellow warning label as shown below:
Warning: Do not turn off this equipment!
* If you are in the middle of a pass
and the temperature drops below
the lower limit during the pass, you
may complete the pass before
shutting down.