==When was it invented?= 
 From 1942: "On February  Todt dined with 
 him; by : a.m. next morning he was dead, his charred remains lying in 
 the wreckage of his Heinkel which had crashed on takeoﬀ at Rastenburg. 
 Hitler was desolate at the loss. He ordered the air ministry to design a 
 cockpit recorder, to install in future planes, to register the cause of any 
 accidents."