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From: ems@amdahl.UUCP (ems)
Newsgroups: net.columbia
Subject: Re: Aviation Week Report on Challenger (2/10/86)
Message-ID: <2804@amdahl.UUCP>
Date: Tue, 18-Feb-86 18:04:07 EST
Article-I.D.: amdahl.2804
Posted: Tue Feb 18 18:04:07 1986
Date-Received: Thu, 20-Feb-86 00:01:48 EST
References: <928@decwrl.DEC.COM> <302@meccts.UUCP> <708@bonnie.UUCP>
Organization: Circle C Shellfish Ranch, Shores-of-the-Pacific, Ca
Lines: 30
Summary: What is the effect of a thermal gradient on the SRB's?

In article <708@bonnie.UUCP>, dpw@bonnie.UUCP (David Williams) writes:
> 
>    My copy of Aviation Week arrived today - the coverage in this issue
> focuses primarily on the SRB and its components as the mechanisms for
> destruction of Challenger.  ...
> 
>    - The two SRBs on Challenger's flight were "high performance" boosters
>      designed for extra thrust through lighter casings and improved
>      propellant burning pattern.  Investigators will examine the
>      possiblilty that the new burning patterns caused turbulence and
>      extreme pressure fluctuations at the gaps in propellant between
>      casing segments.
> 
>    - The propellant in the SRBs is considered to be well insulated against
>      fluctuations in outside (launch pad) temperatures - analysis
>      indicates a temperature of 55 deg. F inside the SRBs.

Hmmm, and yet the outer layers MUST have been cooler (due to their
being in close contact with ice, cold wind, etc ...)

What would be the effect on the boosters of having such a thermal
gradient?  With a warm inside and a cold skin, one is tempted to
think that the inside would be compressed somewhat and the outside
streched a bit; but would it matter?  Would it change the risk
of gaps and poor sealing between segments and/or O rings?

-- 
E. Michael Smith  ...!{hplabs,ihnp4,amd,nsc}!amdahl!ems

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