On 2/24/19 5:37 AM, Rice, Hugh (IPH Writing Systems) wrote:
While HP wasn't a direct defense contractor, we did sell a lot of test
equipment to defense contractors. The big American submarines had a Cesium
Standard or two as part of their instrumentation systems. I know little
about the application, but heard it was part of the communication and/or
navigation systems. Maybe some of you have experience with this, and can add
to the story.
None the less, Sperry corporation was a sub-contractor into the greater DOD eco-system, and
integrated the 5061A into some larger system they sold to the submarine builders. Sperry was a
"real" defense contractor, and had to live by all the DOD rules. There were a number
of defense contractors in Silicon Valley, with Lockheed Missiles and Space Company being perhaps
the largest employer in the area. Both my father, and my wife's father were engineers at LSMC for
their careers. We used to joke at my High School that "everyone's dad worked for
Lockheed." Thus, DOD companies were not a foreign concept to me. But they way the DOD
procurement process worked was very unlike how HP worked and interfaced with our commercial
customers.
Yes, and this how you wind up with $600 hammers/toilet seats/aircraft
coffee makers.
It afflicts the space business too - We call it "heritage" - for
instance, you're designing a new spacecraft. A subsystem, or box, or
anything, that already exists, you know the mass and power of, so you
can put it into your "Master Equipment List" (MEL) and only add 5%
margin. Something new, might have to have significantly more margin,
maybe 25% or 30%.
But on most spacecraft you're severely mass and power constrained,
because the rolled up budgets for those are often set by "what did the
last one do" - or maybe you've got the max mass you can send to Mars on
the rockets that are available.
Even if the new design is infinitely superior in performance, the
additional risk of "something new" gets in the way. Most NASA
Announcements of Opportunity (AO, similar to a RFP) say "Technology
shall be at TRL 6, or a plan shall be presented to insure that it will
reach TRL 6 by Preliminary Design Review" TRL 6 = "demonstrated in a
relevant environment" - basically, you've built the box and run it
through thermal vacuum and vibe testing, but maybe you used parts that
aren't screened.
Notwithstanding that the parts list for that heritage box includes parts
that are no longer available, or that have insanely high minimum order
quantity (the mfrs way of telling you, "use another part, but if you
insist") - that's what gets designed in.
And as Hugh points out, there's a whole team of people who look for ANY
discrepancy from the original design. And those people aren't empowered
to make judgement calls about whether the change is good or bad - it's a
change.
One can, in fact, get waivers. Or, you can, if you have sufficient
budget (Hah!) you could say that your primary design alternative leading
up to PDR is to use the Heritage Unit, but you'll be developing a new
one to replace it, and if it's ready, you can pitch it at PDR (or maybe
CDR).
However, it might be easier (from a risk assessment, budget, and
schedule standpoint) to just use the old design. That is, the extra pain
and cost for finding obsolete parts (Rochester Electronics, "the leader
in the trailing edge of electronics" is your friend) is less than the
pain and cost of getting waivers for a new design.
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