Re: Prototype airliners; what is their fate?

Date:         24 Jan 98 02:53:49 
From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
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>What happens to airliner prototypes? Do they eventually
>get modified to production standards and sold to
>airline companies, or do they stay with the maker till
>the end?

It depends.  If it's a true prototype, it may be substantially different
from production models, in ways that make it undesireable or perhaps not
certifiable.  For example, the 707 prototype (the 367-80) has a different
fuselage width than a standard 707.  At best, it would have been an
oddball in an airline fleet.  (One of the MD-8x prototypes, or maybe it
was the MD-90, was actually a different flavor of DC-9, extensively
modified to approximately the new configuration.)

At the other end of the spectrum, the first 777 is a regular production
bird, and Boeing is reportedly preparing it for possible sale to an
airline customer.

>I guess it would cost the manufacturer a lot of money to
>keep and maintain an aircraft (well, maybe not compared
>to the development costs).

Once they've built the thing, it doesn't cost all that much unless they
are flying it, and presumably they'd be paying those costs to fly *some*
airplane if they didn't have the prototype sitting around.

There is the cost of building it in the first place, which is certainly
non-trivial.  However, the cost of diving right into production and then
finding a problem you need to fix on a whole bunch of planes might be
greater than the cost of building a prototype.  Convair learned that the
hard way with the 990, and the stoppage of the 737-600/700/800 production
line was because they found some problems during flight test which meant
modification to the planes which had already been built.

In the case of the 777, Boeing designed the whole process so they could
avoid building a prototype, using computers much more heavily instead.
The 777 gestation was planned for a longer period of time than other
aircraft, and in some cases they tested things anyway (to validate the
computer models), which may mean that Boeing saved little over building
a prototype and doing things the old way.  Their goal was not necesarily
to save lots of money on the 777, but to use it to develop processes
which will help save both time and money on future projects.

>How many prototypes are usually needed till production
>begins?

Rarely more than one for commercial airliners, except for something
really exotic like Concorde.

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Karl Swartz	|Home	kls@chicago.com
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"The average dog is a nicer person than the average person." - Andrew A. Rooney