Why didn't they use their sound signalling device - 5 short blasts - what is your intention, instead of yelling into a bull horn.
As if they would be heard over the engine noise at 20kts.
There is a funny story that did the traps years ago.
Exchanges were heard on MF/HF and recorded. A US warship was operating on the West Coast when a light was seen ahead. Bearings were taken and the risk of collision was deemed to exist. The US warship called the unknown vessel in the plotted position, but got no response.
They repeatedly called stating they were a US warship and if the approaching vessel didn't respond and bear away the USS whatever would see it as an act of aggression and take retaliatory action.
They finally got a response from the Canadian lighthouse they were steaming towards, that if the US warship didn't bear away they would run aground!
I wish I had kept the copy with the actual radio exchanges, the last part was very funny. cheers