A320 pitch control (was: emergency procedure)

Date:         02 Apr 98 01:24:09 
From:         Julian Scarfe <jas1@scigen.co.uk>
Organization: Scientific Generics
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Pete Mellor wrote:
>
> The next step in the degradation path is direct law, which implies
> direct stick-to-surface-position relationship for both pitch and
> roll, and only manual control of rudder for yaw.

Could you clarify the systems for pitch control on the A320 and family for
me.  My understanding so far is:

Direct law: direct relation between elevator deflection and stick position,
with maximum stick defelection corresponding to maximum elev deflection

Alternate law: stick deflection controls lift, with maximum stick defelection
corresponding to maximum permissible loading

Normal law: stick deflection controls lift, with maximum stick defelection
corresponding to maximum permissible AOA (or is the AOA protected in a
different way?)

Is that anything like correct?  How does the pilot select Alt or Direct law?
--

Julian Scarfe