My Dad said the worst thing, for him, on the convoys, happened when a ship was hit. They abandoned them and any survivors, because the main object was to get as many merchant ships to the UK as possible. If they stopped to rescue anyone, the loitering Uboat would pick them off.
They once saw...
Yes, my Dad joined up in 1935 aged 15 (St Vincent) and served until 1968, including Atlantic and Arctic convoys. He died in 1998, not even seeing the Albion return from Gillingham. He started off as a junior seaman (torpedoman) and finished as chief electrician.