Just imagine an airliner flying blind at 35,000 ft in areas
where huge storms are known to reside and the radar is
inoperative.
Don't have to imagine it - I know what its like - and at night.
Many yonks ago in a 737-200 when the monochromatic radar
died (not that the damn thing was in any way useful when it
did work).
Occurred twice in my case on 2 different 732s - both during
the SEA wet.