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From: (no name) (no email)
Date: Fri Sep 21 2001 - 09:56:22 EDT
In a message dated 09/19/2001 2:19:56 PM Atlantic Daylight Time,
writes:
> This seems to be a recurring attitude on the part of recreational boaters.
> I can only assume it stems from a lack of understanding as to what is
> really involved.
> Large vessels cannot respond quickly; period!
> It takes many seconds to even get the rudder turned, and then an eternity
> for the hull to actually respond and begin to turn.
Stopping a large vessel is a big deal that takes miles and many minutes. The
way those big engines are, at sea speed they operate at optimal conditions
that usually take tens of minutes to change to safely to "maneuvering speed",
where rpm changes are easily done.
Collision avoidance is routinely done only by steering. Moving the rudder
normally consists of taking steering control off autopilot and onto manual or
"hand steering", then turning the rudder with the wheel which sends
electrical signals to the steering engine. This can be done, and the ship
begin swinging, in the time that it takes to say: "Switch to hand steering",
"Hand steering", "Ten degrees right rudder," "Ten degrees right rudder", (5
second pause), "Rudder is ten degrees right."
The primary problem the mates on the bridge have with small craft is seeing
them. Yachts offshore are rare. Fishing boats are much more commonly come
across by a big ship. Small craft are very hard to see, due in great part
because they are often white and at a distance blend in with white caps. At
night small sailboat lights are extremely difficult to see. If all boats were
international orange perhaps there would be fewer collisions, but most of the
ship/boat collisions I have heard of have been when the small craft could not
be seen due to fog, rain, dim or no lights or because one or both of the
vessels' watch was asleep as I think was the case in the recent
tanker/fishing boat collision that claimed three lives off Cape Ann. Ships
normally run from 12 to 23 knots, much faster than most small craft so they
can stay away from them if they see them. In all my years in the American
Merchant Marine, sleeping on watch was unheard of, and the vast majority of
bridge personnel were very professional.
The fact that some ships travel blind has been confirmed to me. One
afternoon several years ago I met an engineer that worked on a small
Caribbean freighter. He told me of often going to the galley for a midnight
snack and finding the bridge watch asleep on the settee.
But is not only cargo ships. Last night, as we voyaged from Rockland Maine
to Gloucester Massachusetts, we spotted a green light broad on the port bow.
As it drew nearer it did fall aft a bit, but not by much. Eventually it
showed up on the radar. Although there was a 4-6 foot swell (and we were in
the trough the whole way) there was not enough wind to move a sailboat fast
enough to keep on a collosion course with us, so we decided it had to be a
motor vessel with no bow light. When it got within a quarter mile I got very
nervous, and when I could see the reflection of the green light in the water
with no safe change of bearing, I went half right, did a 180, steaming away
from the oncoming vessel. The boat, which seemed to be a motor yacht,
appeared to never change course. When it passed us and we could see it's
stern light, now off our stern, we returned to our course. It is possible
that if I had continued my course the other boat would have passed close
under our stern, but I did not want to bet much on it. I did not try to
contact them on the radio as, in this case, I felt that the simpler I kept
things, the better. I felt that if the were running without the proper
lights, on a collision course aiming at a stand-on vessel, there was a good
chance the autopilot was steering and there was nobody on watch. I didn't
want to wake them up. That is what Capt. Ron thinks happened when he was
rammed off West End as the boat was originally going to clear him.
In retrospect, if the other guy had suddenly turned right to go under my
stern I might have been in trouble. Perhaps I should have simply turned to a
parallel course to present him with a smaller target and a slower closing
speed. Any suggestions?
>One of my navigating class student once asked me "why do we have to run in
>straight lines from turning point to turning point.
>Why can't we just run in a big sweeping curve. I know where I'm going and
>where I want to end up".
The main reason ships go in straight lines from point to point is fuel
economy.
Norm
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