Produced by J. Hudson & Co of Birmingham since 1870.
The whistle is made of Brass, plated in highly polished Nickel and contains a cork pea to give it an ear splitting Shrill sound measured at 115 Decibels, used by professional referees and the military.
Acme Whistle (Dog Theft Prevention)
Flight Lieutenant Charles Vernon Pereira was a Pilot in 139 Sqn Flying the De-havilland Mosquito one of the fastest aircraft of the war, with his Navigator Sergeant "Taffy" G.H. Gilbert.
He was on the Jena Raid to destroy the Zeiss factory famous for its optics production when his faithful “N for Nuts” Mosquito aircraft lost an engine just before the target due to enemy fire. He also witnessed the two aircraft to his side collide and roll down the hillside in a ball of flames. The BBC made a recording of that raid and broadcast it on “Target for tonight”.
He returned safely (460 miles) on one engine at low level in spite of a narrow escape flying slap over a German airfield with FW 190 Fokke Wulf fighters in the circuit; for some reason they did not intercept him.
Jena was his last Op’ with 139 Squadron and he was posted to 105 Squadron with the Assessment of Ability as a pilot as “Exceptional”. The RAF did not give that assessment easily.
In the photograph, you can clearly see the RAF issue ditching whistles, ACME Thunderers" worn as part of their Aircrew safety kit on their collars for easy reach, reliable even when wet and capable of producing an ear splitting 115 Decibels of sound to alert or warn in an emergency situation.
Photo Credit "Warwhistle.com"