Re: An-124 and wing dihedral

Date:         08 Jun 98 02:57:54 
From: (Niels Sampath)
Organization: i b4 e xcept after c
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In article <airliners.1998.854@ohare.Chicago.COM> kls@ohare.Chicago.COM "Karl Swartz" writes:
>>(caveat: because the tail engine on the DC-10 was off the centreline viz.
>>one engine out scenario)
>The L-1011 has the same issue.  Are you thinking of the fact that the
>DC-10's #2 engine is so high above the centerline, whereas the L-1011's
>is right on it?  That would affect pitch, not yaw, which is what the
>placement of the wing engines influences.  If the #2 engine on either
>aircraft is shut down, it simply because a sluggish twin.

>My understanding was that the DC-10's wing engines are closer to the
>fuselage than those on the L-1011 because they didn't want to put an
>enormous tail and rudder on the thing.  This is at least partly an
>artifact of the #2 engine placement -- the L-1011 appears to have
>greater rudder area, without significantly different tail height,
>because the S-duct allowed them to get the engine out of the way.

Yes I wasn't clear enough in my little caveat.
The DC-10s engine above the centreline (red herring word in retrospect)
affected yaw only indirectly via the resulting  small rudder.
No. 2 engine out is not the issue. No 1  or 3 was/is.
The DC-10 engines had to be more inboard to reduce thrust
assymetry affects  and keep the small rudder effective
should engine 1 or 3 fail.

(for e-mail replies you -might- have to replace 'nospam' with 'lofgren')