Sharon,
I would like to
take the opportunity to explain the matrix I included for yesturday's
telecom. Even with the additional factor of 1.25, the conclusions are
very much the same. See the attached, updated, matrix.
The loads, by themselves,
are not very significant. They are based on all the flexures, in all the
locations, with several launch configurations, and a MUF included. They
do, however, provide a means of defining a requirement, and allow us a simple
means of controlling a qualification test. But, they do not imply
anything beyond that. As a design engineer, I am more concerned with
ensuring that the structure we design will survive the launch
environment. Ultimately, this means that I am concerned about the stress
in the part, and enveloping the critical stress conditions through
testing. The matrix that I sent, shows that we envelope the critical CLA
predicted stress levels for both flexure types, in a combined manner, even
though we do not exceed the combined CLA loads, per the requirement. So,
the point of this matrix demonstrates that any test we design to meet the
combined load requirements of the CLA will not be as severe as the random
vibration static equivalent tests performed to date, so long as we don't use
the random vibration test configuration to provide the load.
With that said,
we intend to re-design the test to meet CLA specified combined loads for both
flexure types. I believe that we can do this by selecting the proper axis
to test and removing two flexures, as required. This will put more shear
load into the flexures under test, without adding axial load that will
overstress the hardware (analysis will ultimately determine the success of this
test). Since this is a change of scope, I will put together a quick plan
to accomplish this and obtain approval from Tom Borden to proceed.
I hope that this
makes a little more sense now. If you have any questions, please contact
me.
Thanks, Erik
Erik A.
Swensen
Deputy General
Manager, HYTEC Engineering Inc.
110 Eastgate
Drive
Los Alamos,
NM 87544
Phone:
(505) 661-4991
Fax:
(505) 662-5179
Web:
http://www.hytecinc.com/hei/index.html