Re: Confusion over 777 variants.

Date:         01 Dec 97 02:33:52 
From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
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>I find this whole line very peculiar. If you think this is a problem,
>I suggest you take a good look at Airbus did with the A-300,  There
>are 11 different models of the A300, they are externally almost all
>identical (yes a few are 2 feet longer and 1 inch taller). But unless
>you have a tape measure with you, I doubt you are going to notice.

Not quite -- the first two A300s built (A300B1 models -- add yet another
to your list!) were 167'2" (50.97m) long.  The A300B2 and A300B4 were
stretched to 175'11" (53.6m).  The slight difference you mention is from
these versions to the current -600 models, which have a 21" (0.52m) plug
aft of the wing along with the A310's rear fuselage and other changes.

>There is nothing about the models numbers that tell you very much.

To make it even more confusing, the early versions are often referred
to as simply an A300B4 (or A300B2) while the current models are called
A300-600.  Yet the *correct* designation for the current models is
A300B4-600!

We could further confuse things by talking about the A300B4-2C, which
was rechristened A300B4-200, and various other early designations.  To
really make a mess, how 'bout the A300B10 and A300B11, which developed
into the A310 and A340, respectively?  :-)

>In reality, each airline ends up with its own model. For instance -38
>designation such as 747-438 or 747-338, 767-238, 767-338 belong to
>QANTAS Airways. There are in fact externally the standard aircraft,
>but the internal configuration, certification, engines, MGTOW are
>often unique to that particular airline.

Even this gets muddied, unfortunately.  There are a pair of 747-451s
(51 is Northwest's Boeing customer code) flying around which are
indistinguishable from 747-422s (22 is United's code).  They were
built for Northwest but cancelled at the very last moment (one had
flown in Northwest colors already).  United took them, and in the six
or so months between signing and taking delivery, Boeing converted
them to United's specifications -- but they kept the -451 designation.

McDonnell-Douglas made it easy with the DC-10.  There are just four
models:

   -10   medium-range model
   -30   long-range model
   -40   -30 with JT9D engines
   -15   -10 with high-rated engines from the -30

Or is it easy?  Two DC-10-30s can be very different indeed, despite
having the same model designation.

--
Karl Swartz	|Home	kls@chicago.com
		|Work	kls@netapp.com
		|WWW	http://www.chicago.com/~kls/
"The average dog is a nicer person than the average person." - Andrew A. Rooney