A feature of the times. Immediately after WW2 Both the Handley Page Hermes and the Avro Tudor prototype airliners crashed departing their factory airfield in early test flights due to reverse control assembly, the former on the type's maiden flight, the latter killing Roy Chadwick, the aircraft's (and the Avro Lancaster bomber) chief designer.
https://aviation-safety.net/database...?id=19451202-0
https://aviation-safety.net/database...?id=19470823-0