Re: Airbus Gust-Load Alleviation systems

From:         Pete Mellor <pm@csr.city.ac.uk>
Date:         31 Jul 96 12:29:41 
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Martin Fiddler <m.fiddler@staffs.ac.uk> asked:

> So, is there such a system as I have described?

Yes, quite definitely. The Load Alleviation Function (LAF) is
performed by the Spoiler and Elevator Computers (SEC). The SECs
(there are three of them) control the spoilers in all of their
roles: assisting roll control, speed brakes, gust load alleviation,
ground spoilers.

> Does it work like I described it?

I haven't trawled through the manuals for the aerodynamic aspects
of LAF. My main interest is the Flight Control System. I would be
interested to learn more about what goes on out there on the wings.

> Is it's complexity worthwhile -

I've often wondered! Certainly it must add to the workload and
complexity of the SEC software.

> - considering the highly optimised airbus wing that may well
> need protecting from high bending moment, and the availability
> of the SEC computers it may be a good system?

I heard early on in the life of the A320 that weight had been
saved in the design by "optimising" the wings. Later, someone
(I forget who) contradicted this, and said that the A320 wing
is perfectly "standard" in all aspects of design.

Since you have been to a lecture on the wings, perhaps you could
clear this one up for me?

Cheers!

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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