When did the coventry Blitz start?

Coventry was part of Britains industrial centre of production, among, of course, many other places. The Luftwaffe was guided by the transmission of radio beams sent from 2 different locations, when the beams intersected the Bomber was over Coventry. At this time bomb aiming from an aeroplane was very haphazard indeed & the targetting of individual sites was very hit & miss (Mostly miss) & therefore civillians were attacked as much as military targets. Incendiary bombs were dropped to set fire to buildings, and once alight these fires attracted more of the same.