Howell was a successful fighter pilot for the Royal Flying Corps during World War One. After the war, he stayed on in England and was selected by aircraft manufacturer Martinsyde Ltd to pilot the plane it entered into the Australian Government's air race to complete the first flight from England to Australia in less than 30 days.
Howell and his navigator/engineer George Henry Fraser were killed 10 December 1919 when their Martinsyde A1 aircraft crashed near Corfu. The last page of his War Service Record (page 52 of 52) has report of his death from British Naval attaché in Rome. His body was recovered several days later and shipped back to Australia. Fraser's body was never recovered.
After his death, Howell's father, Ernest, published a pamphlet in which he suggested that the start date and terms of the air race had been changed to advantage Sir Ross Smith and negligence on the part of Martinsyde Ltd. He called for an enquiry by the Commonwealth government into his son's death, but this was not granted.