A mandatory AOA indicator as apart of stby instruments can be a solution.
If you lost everything fly the AOA.
In fact, a version of this is in use and can be purchased as an option for A 330.
If All ADRS are gone, PFD displays a green band, simply adjust speed to fly within.
Ironically, T 38 Talon manufactured 1968, we used to fly green AOA light on approach regardless weight and Flap.
Last edited by JABBARA; 9th June 2009 at 07:52.