Hi Trevor,
The 18" Mk VIII torpedoes were designated for aircraft, whereas the larger 21" Mk VIII were used by submarines and surface launched ships.
IMHO the part appears to be the external Hydrostatic piston and pendulum depth control cover - the black oval shape would be the part that "flexes" and relays the external water pressure to the internal pendulum mechanism. The mechanism controls the torpedo set depth and performed by mechanical linkage to the depth planes located on the tail section.
But then I could be completely wrong.............. LOL
Cheers
Drew
Good Evening Trevor,
Yes definitely "twins", perhaps not identical but twins none the less! LOL
The minor differences could be due to different manufacturers or different MOD design variations - but still same function as previously posted above.
Cheers
Drew
Far more common that this Mk1 version - noticed the the large extensive "ribbed" diaphragm section................................:tongue:
Thanks very much - pictures are worth a thousand words!See on You Tube the film Aircraft Torpedo | Royal Air Force instructional film (1942)