Re: A3XX vs B747-600 (was: Airbus lawsuit coming?)

From:         Pete Mellor <pm@csr.city.ac.uk>
Date:         23 Aug 96 13:44:59 
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Jean-Francois Mezei <jfmezei@videotron.ca> writes
(Mon Aug 19 04:30:29 1996):-

> Well, whether Boeing or Airbus build a brand new plane, it does not
> necessarily mean that they start from nothing. Both already have
> computer systems (FBW). Airbus already has experience in adapting its
> 320 systems to its other planes (340 and the latest model of the 310).

A320/319/321/330/340 cockpits are virtually identical (except that
the A340 has four engines, hence four thrust levers, etc.). This
was a deliberate design decision by AI intended to reduce the time
and cost of type conversion training. Presumably it also reduced
the design time for the later models.

> And before I would beleive that Boeing can just extend the 747 without
> redesign costs etc, I would like to know more about what changes had to
> be done between the 747-100 and 200, 200 to 300 and 300 to 400.

I have visited the cockpit while flying on a 747-200, and on a 747-400.
The 200 felt cramped. *MASSES* of dials everywhere, and a busy flight
engineer in the rear starboard seat (facing sideways). After my visit
to an A320 cockpit a few years back, and studying the A3XX instrument
layout, it was all totally unfamiliar.

By contrast, the 400 cockpit felt open and spacious. The layout of
the screens was immediately familiar to me from the A320 (PFD and NAV
for C and FO, plus two central EFIS/ECAM screens). The actual displays
on the various screen looked oddly familiar, too. The only really
striking difference from the A3XX was the presence of control columns
instead of side-sticks.

(I asked the captain of the 200 what he thought of all this new-fangled
glass-cockpit automation. "Sooner the better!" he said. :-)

> If Airbus is to build a new big plane, how much of its 340 can be
> re-used ? (Look at what they were able to do with their 310 to make the
> 600 super-guppy transport).

Airbus claim that there is nothing revolutionary about the computerised
flight control system on the A3XX. They point out that they have been
steadily increasing the level of automation ever since Concorde.
Certainly, the basic "fail safe" computer architecture was first proved
on the A300/310 slat and flap control. I would say it is a racing
certainty that the "fail safe" computer box will be the main building
block in any future Airbus design, however the individual boxes are
interconnected.

Peter Mellor, Centre for Software Reliability, City University, Northampton
Square, London EC1V 0HB, UK. Tel: +44 (171) 477-8422, Fax: +44 (171) 477-8585
E-mail: p.mellor@csr.city.ac.uk
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