Somewhat OT staten island ferry

It's a sad day for the Staten Island Ferry, and sadder still for those
who have lost family and friends.
It will be interesting to watch the accident investigation. One
breed of the newer diesel electric boats never could reverse anywhere
near as fast as the older Uniflow reciprocating steam versions. Alas,
I think they're all retired now.
Years ago I asked to ride in the engine room of the Cornelius G.
Kolff for an afternoon and the department of Marine and Aviation
actually let me. The Uniflow had the advantage of being able to switch
from full ahead to full reverse in a heartbeat - not that you'd want
to do it! The engine looked for all the world like a large two story
marine diesel, camshafts and all, except for the occaisional whisp of
steam. You could see the crankshaft and connecting rods behind large
glass port holes.
I had grown up on the Hudson river side wheeler Alexander
Hamilton, whose three cylinder triple expansion powerplant required
something of an act of Congress and a whole lot of skill to reverse so
as not to stop the high pressure cylinder on dead center although I
believe you could bypass to the intermediate in such cases.
The Merrill class Staten Island ferryboats just simply reversed,
and if the engineer was in a hurry you never even saw the crank slow
down.
Anyone have any experience with new variable pitch wheels on
large craft? Can you effectively do the same thing?
Chas Morrill
Reply to
chasmorrill
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You can reverse the propeller shaft as fast as you want but you still have to deal with cavitation when you suddenly reverse rotation or change pitch direction. Your reversing prop will end up grabbing a vacuum so to speak. Stopping in a boat length is doable with modern destroyers, but they use all kinds of tricks they don't want to talk about. I have been on sea trials on a high speed catamaran with over 30,000 horsepower driving water jets. Thirty knots to full stop was less than five seconds using reversing buckets on the nozzles. It was not as spectacular as I had expected. No shudder or hull shake. If you stood with your feet together you would have to step forward to catch yourself. It was then that I realised we decelerate at this rate in a car all the time. Randy
It's a sad day for the Staten Island Ferry, and sadder still for those who have lost family and friends. It will be interesting to watch the accident investigation. One breed of the newer diesel electric boats never could reverse anywhere near as fast as the older Uniflow reciprocating steam versions. Alas, I think they're all retired now. Years ago I asked to ride in the engine room of the Cornelius G. Kolff for an afternoon and the department of Marine and Aviation actually let me. The Uniflow had the advantage of being able to switch from full ahead to full reverse in a heartbeat - not that you'd want to do it! The engine looked for all the world like a large two story marine diesel, camshafts and all, except for the occaisional whisp of steam. You could see the crankshaft and connecting rods behind large glass port holes. I had grown up on the Hudson river side wheeler Alexander Hamilton, whose three cylinder triple expansion powerplant required something of an act of Congress and a whole lot of skill to reverse so as not to stop the high pressure cylinder on dead center although I believe you could bypass to the intermediate in such cases. The Merrill class Staten Island ferryboats just simply reversed, and if the engineer was in a hurry you never even saw the crank slow down. Anyone have any experience with new variable pitch wheels on large craft? Can you effectively do the same thing?
Chas Morrill
Reply to
R. Zimmerman
I was on the USS King when the Captain allowed the XO to take the ship into dock in Okinawa. His timing was a little off. It was pretty impressive to see those timbers flying up into the air, people running for their lives and we deck people escaping to the other side of the ship. I don't think we were moving at more than a slow walk.
I've also handled lines on shore trying to get a merchant ship in with a strong off shore wind. I feel for the crew of the ferry. Sometimes the wind just takes over and you can't do a thing about it. Especially in the gusty conditions in the northeast yesterday.
Earle Rich Mont Vernon, NH
Reply to
ERich10983
I grew up on Staten Island and the Sandy Hook pilot (harbor pilot captain) who lived across the street commented (back in the 50's) that landing a ferry on the SI side was difficult, because of the tide forcing water through the Kill Van Kull. The result was a very strong current, one way or the other, across the entrance to the boat slips. Those Captains are very stable, very responsible, very skilled and highly paid (no pot-heads need apply). Therefore, chances are it's a mechanical problem of some kind.
Reply to
larsen-tools
Looking at the bright side of things, this means full employment for SI lawyers......... filing about a thousand soft tissue neck and back injury suits.
Reply to
larsen-tools
Reported that the pilot tried to kill himself after the accident. He was apparently slumped over the controls just before the accident happened. Probably somebody else in the area noticed the problems and did what he could to stop the ferry before it hit.
-- Bob May Losing weight is easy! If you ever want to lose weight, eat and drink less. Works evevery time it is tried!
Reply to
Bob May

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