radar alt redundancies?
Question to engineers/system designers/knowledgeable 73NG pilots:
- Is there no redundancy for the radar altimeter? If yes, why does the FMGC not use it?
- Why is rad alt the only source of truth? What about 'classical' alt (and it's five redundancies), GPS alt, DME distance (should be on any ILS no?), IRS alt etc. etc.??
Shouldn't the A/P and A/T disconnect if any of these sources do not reconcile??
If the autopilot only relies on rad alt without considering any other parameters, this accident shows quite a shocking design weakness, no? I would understand it on the 737 prototype, but the NG?
Please enlighten the rest of us...