Arguably, taking off along a route where one could potentially be stuck in icing for an extended period, in an aircraft not capable of that, is the definition o

Arguably, taking off along a route where one could potentially be stuck in icing for an extended period, in an aircraft not capable of that, is the definition of poor pre-departure decision making. Commercial airliners have relief to dispatch with malfunctioning anti-ice gear. The procedures almost always dictate that flight in known or forecast icing conditions is prohibited. Basically, if it’s not summer and there’s a cloud in the sky you’re not going. Icing is not something to mess around with in an aircraft not properly equipped for it.