Re: DC-10 Modifications after ORD

From:         -z- <trsmith@prado.com>
Organization: Altopia Corp. - Affordable Usenet Access - http://www.alt.net
Date:         21 Oct 96 13:31:39 
References:   1
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Jim Messina wrote:
>
> I read the long NTSB report posted here two months ago about the AA DC-10
> crash at O'Hare years ago. I am still uncertain what modifications were
> done to the DC-10 fleet as a result. Can someone summarize them. Thanks
>
> Jim Messina
  As far as physical modifications to the airplane:
    #1:  Two (2) fasteners which are located on the upper spar web of
the wing pylons, immediately forward of the aft pylon-wing mount
bearing, were converted to 'countersunk' fasteners instead of protuding
head 'huck-bolts' ( or the modern equivalent 'hi-loks'). This was to
avoid damage to the upper spar web and aft pylon bulkhead just in case,
in a future pylon installation, the aft end of the pylon should travel
upward and contact the wing mount clevis.
    #2:  Anti-retract valves were placed in the hydraulic return lines
of the outboard ( left and right ) slat actuators, immediately outboard
of each wing pylon. This prevents sudden draining of the actuators in
case another pylon tears out the lines upon break-away. The drain
prevention prohibits the slats from retracting into the wing.

    Non-physical changes:
       Many changes to the methods of pylon removal, installation.
Perhaps some flight emergency procedures training ( not sure on this one
).

-thomas-