Chazz: I was a Midshipman on a small inshore defence vessel - on the foredeck - supervising mooring lines - when there was a cry from the bridge "Emergency!! Let go all forrard"!!"
The manoeuvring engine single screw had cavitated due to an emergency change from Ahead to Astern. - This caused a "backed to starboard! " event - as you also experienced. I was told afterwards it was natural due to the density of air and water when cavitating, when a large quantity of air is "gulped-down" to the bottom of the screw, and the cavitation therefore causes reverse "paddle wheel" side thrust.
Not being quick enough, the Mid on one mooring rope (fore-spring) left it cleated, whereby the momentum of the ship simply snapped the 2 inch rope like rotten cotton! As the broken end whipped back it destroyed the hand-rails along the side of the foredeck.
Cavitation can cause a loss of control or response to the telegraph, so the telegraphist must always take care with his instructions and timing to the engine room... ALWAYS STOP-PAUSE - between Ahead and Astern. The Bridge MUST understand how the ship will respond to their instructions.
K2
The manoeuvring engine single screw had cavitated due to an emergency change from Ahead to Astern. - This caused a "backed to starboard! " event - as you also experienced. I was told afterwards it was natural due to the density of air and water when cavitating, when a large quantity of air is "gulped-down" to the bottom of the screw, and the cavitation therefore causes reverse "paddle wheel" side thrust.
Not being quick enough, the Mid on one mooring rope (fore-spring) left it cleated, whereby the momentum of the ship simply snapped the 2 inch rope like rotten cotton! As the broken end whipped back it destroyed the hand-rails along the side of the foredeck.
Cavitation can cause a loss of control or response to the telegraph, so the telegraphist must always take care with his instructions and timing to the engine room... ALWAYS STOP-PAUSE - between Ahead and Astern. The Bridge MUST understand how the ship will respond to their instructions.
K2
