Re: DC 10-ski topples on to its rear when unloaded!

From:         drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Organization: Boeing Commercial Airplane Group
Date:         24 Feb 94 23:40:47 PST
References:   1 2 3 4
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In article <airliners.1994.952@orchard.chicago.com>,
Dickey Bradley F <bdickey@cc.brynmawr.edu> wrote:
>In article <airliners.1994.929@orchard.chicago.com> John.Stone@bris.ac.uk writes:
>>
>>  I understand that 747's (and possibly others) carry depleted uranium in
>>  the nose for ballast - lots of mass in a small volume. Don't suppose
>>  you could say that _they_ were badly designed :-) Does create a bit of
>>  local concern when they crash, though.
>
>I think that the isotope they carry is the U^238, which is a harmless and
>non-radioactive one (well, OK a bit radioactive, but so is Connecticut).
>The report of this indeed caused a stir during the Lockebie incident, when 
>the locals found out about it.  The Scottish environmental groups realized
>that there was no danger, and let it lie; I do remember one spokesman for
>GreenPeace, I think, who was reported to say;
>"I would be more afraid of the thing dropping on my head than of the danger 
>to the environment later" [sic].
>
>So Pan Am certainly was using Uranium as balast, supposed to be quite cheap,
>as well as the qualities you mention - small and heavy.

Actually, I think everyone is referring to the mass balance in the
elevators.  They used to be depleted uranium, but because of the ecological
extremists (and I am by nature a tree-hugger myself) we have changed to
lead, which isn't as efficient (dense).  Brad is correct about the relative
danger from the radiation in his note above. 

BTW, mass balance in the elevators, and other control surfaces, is to
prevent flutter damage, and well as make the controls easier to move.

Terry

-- 
Terry
drinkard@bcstec.ca.boeing.com
"Anyone who thinks they can hold the company responsible for what I say has
more lawyers than sense."