Re: 747

Date:         10 Jul 97 17:46:12 
From:         kls.spam-be-gone@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
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>> A cousin of mine was flying Sea-Tokyo on a NW 747 on Monday when the
>> captain shut down two engines near Alaska and returned to Seattle.

With two engines out, I'm almost certain the regulations would have
required them to divert to the nearest suitable airport.  If they were
far enough into Alaska, that would have been Anchorage.  Closer to
Seattle, and if an emergency had been declared, they could have gone
to Ketchikan, or turned back to Vancouver.  The only way they could
have legally returned to Seattle if indeed two engines were out is if
Vancouver (and perhaps Paine Field and Boeing Field) were unavailable
due to weather or some other problem.  (United lists Boeing Field as
an alternate, but oddly does not list Paine Field.)

>P3 Orion are often cruised on 3 engines to improve time on station.
>Fewer engines running generally means better fuel consumption all
>other things being equal.

The P3 Orion loiters on *two* engines -- they shut down both of the
outer engines (#1 and #4).  The asymmetry of shutting down only one
engine would require enough rudder to counteract the tendency to yaw,
which would reduce or elimnate the reduced fuel burn (and hence loiter
endurance) which is the point of the exercise.

--
Karl Swartz	|Home	kls@chicago.com
		|Work	kls@netapp.com
		|WWW	http://www.chicago.com/~kls/
Moderator of sci.aeronautics.airliners -- Unix/network work pays the bills