Re: Opening a door in flight

From:         drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Organization: Boeing Commercial Airplane Group
Date:         01 Nov 94 00:06:53 
References:   1 2 3 4
View raw article
  or MIME structure

In article <airliners.1994.1661@ohare.chicago.com>,
Paul Callahan <wpcallah@rwasic17.aud.alcatel.com> wrote:
>
>They said that there was much customer interest in "easy"
>to open doors, which did not have to move inside first.
>This was memorable, because I thought the inherent safty
>of the plug design, would keep it for a long time....

The 777 cabin doors are plug type doors.  That is, the structure of the
door is wider than the opening in the door frame structure.

>>(Cargo doors are another matter.  The L-1011 uses plug cargo doors,
>>but it's the only jet that comes to mind for which this is the case.
>>The DC-10 -- and 747 -- certainly do not have plug cargo doors.)
>>
>
>Why not plugs here?  Again, it's easy to argue that they
>have better safty, as in the DC-10 reference.  Does anyone
>know if this is due to ease, cost, or the fact that more
>cargo can be pput next to the door, if you don't have to
>leave space to move the door into the cargo area, and then
>rotate it?

Lost cargo volume for the twin-aisle airplanes is economically significant
if the main cargo doors open inward as a plug door does.  That is one lost
container or pallet position, per door, or roughly 10% of your available
revenue cargo volume.  This is because the doors are large enough to
accomodate containers and pallets, unlike most single-aisle airplanes (the
A320 is the only exception that comes to mind).  The smaller bulk doors
don't have this problem, and can generally be kept as plug doors, though
there is some marketing pressure to turn them into outward opening doors to
gain that last couple of cubic feet of volume.  The 757, for example, has
outward opening cargo doors, but is loaded bulk only.     

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."