Re: Domestic Aircraft

From:         kls@ohare.Chicago.COM (Karl Swartz)
Date:         22 Jan 93 02:59:52 PST
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Michael Weiss asks:
>This had me wondering something.  Clearly, aircraft with long ranges (such as
>the 767, 747, DC-10, etc., etc.) can be flown directly from the US to any
>nation, so delivery is no more complicated than flying to the appropriate
>country.  What about the shorter-range aircraft, like the 727 and 737?  How
>do they get from the US to, say, the middle east?

And Robert Dorsett replies:
[interesting stuff about EROPS deleted]

As a note to any other readers who had to read this a few times to
really follow it, Robert is talking about extended range operations
in a fairly general sense, not the more familiar and controversial
specific topic of flying twin-engine aircraft on trans-oceanic
flights.  One example of the issues involved beyond overwater ops
is the recent cancellation of United's Round-the-World offerings,
which was the result of the pilots refusing to fly the leg between
Hong Kong and Delhi.  United chose to operate this segment with a
767 using a route that would pass over the Himalayas; the pilots
objected because of the 767's inability to maintain sufficient
altitude over the mountains with one engine out.  (Why exactly the
route went over the Himalayas is not entirely clear to me, since
it would be quite easy to go slightly south and avoid them, but that
is another topic.)

>Extended-range twin operations is often referred to as "ETOPS."

My favorite interpretation of that acronym is "Engines Turn or
Passengers Swim," which I've heard is popular amongst pilots.  :-)

>Ferry operations, which you refer to, are simply a subset of a generic EROPS
>class, minus the unique particulars which might qualify an airplane for max.
>range.

By "unique particulars ... for max. range" are you referring to extra
fuel tanks?  As has been mentioned elsewhere the standard tankage can
be extended with fuel bladders, and often is for long ferry flights,
so the basic aircraft may indeed not be equipped with sufficient fuel
tankage for a long delivery flight.

Other equipment, though, such as additional redundancy required for a
twin to fly regular ETOPS wouldn't necessarily be on the aircraft.  I
doubt they'd add that stuff just so they could deliver it!

>for long-range delivery flights, there is no alternative but to stage
>it in short hops

This simply isn't true, unless you consider "short hops" something
approaching transcontinental range, where I'm rather ethnocentrically
referring to the North American continent.  Consider Hawaii.  The
closest major airport is San Francisco, nearly 2,400 air miles away.
Yet Aloha operates 737s and Hawaiian has DC-9s; Aloha Commuter even
has De Havilland DHC-6 Twin Otters!

I'll bet the jets flew there from the U.S.  That's an awful stretch
for the Twin Otters.  They may have come from the other direction --
Midway Island is the closest place with an airport, I believe, but
even with that route and several additional island hops from Asia
there are 1,400 mile legs which are probably at the limits of, if not
beyond, the normal range of a Twin Otter.  Of course that's turning
into a rather expensive delivery odyssey for an aircraft made in
Canada!

The alternative is to add fuel bladders and carry a maximum load of
fuel, with as little else as you can get away with.  Perhaps in some
cases it may even be necessary to go to the extreme of stripping out
the interior to eliminate unnecessary weight.

While it's reaching beyond the topic of airliners a bit, there is of
course yet another option for small aircraft -- go over aboard a boat
or fly inside a bigger aircraft.  (The Air Force ferried F-117A Stealth
fighters to Europe and back inside C-5B cargo jets, though this was
before their existance had been acknowledged and may well have been
more for secrecy reasons than range limitations.)

--
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