Re: Are Two Engine 757 & 767 Jets Dangerous?

Date:         12 Dec 96 03:49:25 
From: ( 0 Falke_Charlie phone dist )
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> I'm pretty sure the A330's engines are attached at the same point as
> the A340's inboard engines.  If so, the A340 is carrying around more
> rudder than it needs.  Alternately, if the A330's engines are closer
> to the fuselage to allow use of a tail and rudder that are adequate
> for the A340, then drag is greater than would be the case for an un-
> compromised design.

   The A330 engines do mount at the same station where the inboards do
on the A340, but it doesn't mean that the rudder is too big.  The
moment arm of a failed outboard 34K engine twice as far out from the
centerline as a failed 68K engine is the same, and requires the about
the same rudder deflection, all else being equal.  The outboards are about
twice as far out as the inboards on the A340.

Charlie Falke                Pratt & Whitney Aircraft
System Test Team Leader      400 Main St. M.S. 121-05
203-565-9063 x1261 fax       East Hartford, Ct 06108