From the hunt
“Tally-ho” started as the cry riders gave in an English fox hunt when they spotted the fox, to set the hounds after it. Dictionaries record it from the 1770s and trace it to taïaut, a French hunting cry.
To the Battle of Britain
In 1940 the Royal Air Force made it a radio call. On 26 August 1940, Air Vice-Marshal Keith Park, commanding the fighter group defending London, told his controllers that pilots must report the enemy “immediately on sighting” and gave the model message:
“Tally Ho! Thirty bombers forty fighters Angels twenty proceeding North Guildford.”
That one line also has Angels: the height, twenty thousand feet.
TALLY today
Modern brevity codes keep the short form. TALLY means a pilot can see a target or non-friendly aircraft; NO JOY is the opposite, “aircrew does not have visual contact.” For a friendly aircraft the pair is VISUAL and BLIND. More in fighter pilot slang.
