Sea Launch User's Guide

Test-verified
model required for
final CLA
The spacecraft must have positive margins of safety for yield and ultimate
loads. These loads are generated from limit loads using factors of
safety no less than those displayed in table 6-3. Limit loads for the transient
flight events are calculated by Sea Launch in a coupled loads analysis
(CLA) and provided to the spacecraft customer. Limit loads for the
quasi-static events are calculated using the Sea Launch quasi-static load
factors for ground handling, transportation, and flight. The CLA limit
loads used for verification must be generated using a test-verified model
for the spacecraft. Model verification of the spacecraft can be performed
either by modal survey or sine test.
Fatigue factor of
safety
Compliance to the Sea Launch fatigue environment is demonstrated by
showing positive margin to the fatigue spectrum (section 5, table 5-1)
after increasing the number of cycles at each load level by a factor of
four.
Customizable test
requirements
Sea Launch requires that the spacecraft structural capability be demonstrated.
The Sea Launch qualification requirements on the spacecraft are
standard industry practice, but can be modified to meet specific spacecraft
needs. Structural testing on the spacecraft generally depends on the
design heritage. Unique qualification tests can be developed by the
spacecraft customer to account for design heritage. Sea Launch will work
with the spacecraft customer by evaluating customer proposed testing to
support the spacecraft integration process.
The following tests are accepted by Sea Launch for demonstrating structural
compliance. If the qualification approach that best suits your spacecraft
is not discussed here, Sea Launch will evaluate your proposed alternative
to ensure spacecraft compatibility.
Model survey test
A CLA will be performed with a test-verified spacecraft model before
flight to verify that the maximum expected limit loads for the spacecraft
and the testing performed on the spacecraft structure are in compliance
with table 6-3. Model verification of the spacecraft can be performed either
by modal survey or sine test. Repeat-mission spacecraft do not require
further testing.
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