[SS-VehDev] NC Matrix

[Lakestake Rocketry]

OK Bill, you asked for comments... These are not warranted to be
on target, but hopefully they can stimulate some converstaion.

What are the environments requirements/limitations of our nosecone
mounted instrumentation? I suggest we be more specific here.
What are the acceptable temperature, vibration and 'gee' extremes?
For these numbers I think we can specify something standard and
have the payload team get back to us if they have something more
delicate in mind.

You mention a 100fps impact of the airframe, what impact force will
this translate to for the instruments after insulation by the airframe
and payload bay? What shock/vibration/heat insulation does the
design then need to deliver?

Is 10 seconds enough for the heat time? I agree that the burn will
be short, but we may still be heating (or at least not cooling) for the
first part of our initial coast while we are still in some atmosphere.

As we may be talking about composites on the nose, fins or airframe
'too hot' may be lower than the 1000' you have specified. Do we have
any sounding rocket heating data to work from? It would be interesting
to have an idea what environment we will be facing.

What about adding a Concept 4 to the matrix. It would be a hybrid NC
formed from a composite cone with wither a metal tip or metal sheathing.
We might be able to get the best of both worlds.

Do you have definitions for each of the columns? I think many are
self-explanitory, but as we are dealing with an international team it
might be good to jot down a quick sentence or two about what you
are intending.

I am not sure on what basis the numbers in the columns 'Legacy',
'Engineering Evaluation' and 'In/Out' are generated.

Could a short list of the factors that weighed into each number be included
with the matrix? This would allow other team members to understand and
contribute to how the numbers are derived.

I notice a two in the availability column for Titanium. Isn't this already 
handled
by our vendor? If so shouldn't this number be higher as this is no longer an
impediment to selecting that design? I agree that Carbon is harder to find,
but there are many good sources in LA, I have never had a problem getting
just about any grade on a moment's notice. My suggestion, lacking your
insight as to what other factors went into the numbers, is that the 
availability
values should be 4 across the board.

Hope these thoughts help. Anyone else have ideas? That's what we are on
the team for!

Matt

On 9/8/05, william colburn <space1space at sbcglobal.net> wrote:
> 
> The matrix gives about the same score for all
> candidates. Since it is probably about +/- .5 or so,
> the values are really the same.
> 
> I am rather in favor of Andrej's composite-over-
> honeycomb version. It comes out about even with the
> others and even better if he uses carbon composite
> too.
> 
> The idea of adding the attachment points for
> instruments and hardware as nutserts is appealing too.
> 
> The Titanium is the high tech version and would be
> free to us. It suffers from needing insulation for the
> inner workings.
> 
> Comments?
> 
> BC
> 
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