Re: Fourth landing gear on MD aircraft ?

From:         simonlc@ozemail.com.au (Simon Craig)
Organization: OzEmail Pty Ltd - Australia
Date:         12 May 95 03:22:46 
References:   1
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>         Is the 4th gear a feature that only MD now uses (as is the tail
>         mounted 3rd engine) or will that feature also be used by other
>         major manufacturers ?
>
>         Is the purpose of that gear to provide additional breaking power
>         or as a structural feature to support the weight of aircraft during
>         touchdown ?
>
>         If the 4th gear was required to support the weight of aircraft, was
>         this required because they used less structural metal in the fuselage,
>         or because of a weird and new design or because they wanted the plane
>         to be able to carry more weight (cargo/passengers/luggage) ???

Goodness, no.  This is a normal feature of an MD11, which you described so
well.  But it is not a new feature.  The centre main wheel is also used on
the DC10, its predecessor, although I believe the very early model DC10s
did not have this centre wheel set up.  I think it is mainly a structural
thing, although it does have a standard brake on each wheel.

Simon Craig

simonlc@ozemail.com.au