BAe 146 Inner Wing De-Ice
As a relative newcomer to the 146, I was just wondering why we wait until after the "Ice Detect" light has gone out before we switch on the "Inner Wing De-Ice"? Surely if you're in icing conditions for a considerable amount of time, eg 10-20 mins, it would be better to have it on.
Is there a specific reason for this action or is it just a hangover from turbo-prop days with the "Boot" system which found it's way into the SOP's when the aircraft was being designed??