 He also criticised the ATSB for failing to take notes when interviewing witnesses, and for its poor presentation of evidence.When the air traffic controller responsible for the Beechcraft received the open-microphone transmissions, he alerted his supervisor that he was concerned the pilot could be suffering from hypoxia.The controller and his supervisor completed the standard checklist which, at the time, did not include a procedure to follow in the case of incapacitation or hypoxia.