Posted by: towmasters | October 14, 2008

More Thoughts On The River Clyde Tragedy…

Having read through the MAIB report on the T/V Flying Phantom a second time, some more things come into focus. This provides both answers and more questions.

The M/V Red Jasmine was making about 6 knots SOG going up the Clyde, including the 1 knot of flood behind them, and they only had to go under (not through) one bridge on the way up to Shieldhall Riverside Quay in Glasgow. That was the Erskine Bridge, which is of the cable-stayed box girder type and, as such, was not navigationally significant to the passage in terms of being a restriction to the width of the channel or an obstacle that had to be maneuvered through.

As pointed out in the Risk in Ship Assist work post on the Kennebec Captain blog, bow and stern tugs are commonly used to maneuver ships through narrow bridges in Europe. But there are no narrow bridges on the Clyde between the river’s mouth and the docks. So is there some other factor, unknown to us, that requires this tug scenario to effect a safe transit? Or is this possibly just another case, in a long line of cases, that simply revolves around the principles of “that’s the way we’ve always done it” and “it always worked before.” Many people have cut their own lives short, along with the lives of others, because of their blind belief in these closely-related principles.

What is the significant advantage gained by having a non-tractor bow tug in front of a ship doing 6 knots? That tug will undoubtedly be using much of its power and maneuvering capabilities just to stay more-or-less in position ahead of the ship. The job of the captain and mate was made significantly more difficult and dangerous because of it, and all this before any steering forces can be brought to bear on the ship. What a waste. If there is some advantage so great as to be worth the high risk I’d like to know what it is.

As any ship or vessel starts moving ahead through the water its pivot point also moves forward. The faster the ship goes the farther forward it moves. This means that the bow tug(s), wherever they may be positioned, will (if equal to the stern tug in bollard pull and maneuvering capabilities) always be at a big disadvantage in terms of how much steering force they can exert on the ship. It would appear to be a more effective practice on the Clyde (and elsewhere) to simply have the stern tug steer the ships through the bends using the indirect mode (pulling the stern to one side or the other with the ship line). Beyond that, while somewhat narrow, the Clyde’s channel doesn’t appear to be so narrow that it would preclude the use of tugs alongside, especially if you only used them on one side or the other. Even if one insisted on using the bow tug(s) as the primary steering, this could still be accomplished with them alongside with a line up, pushing or pulling as needed. Again, why risk having them in front?

The actions of the pilot immediately after the tripping of the Flying Phantom only serve to confirm the unnecessary risk of the bow-tug-in-front scheme. After Flying Phantom’s hawser parted the pilot simply used the ship’s rudder (hard over to port) and a pull to starboard from the stern tug Warrior III to effect a safe return to the middle of the channel. They then proceeded safely on through dense fog, with no other tug to help them, up to the Shieldhall Quay where they were met by another assist tug. Couldn’t it have been done this way from the very start, without the loss of life? Has this not occurred to anyone in a position to call for a change in procedures?

There are, in fact, some extremely narrow bridges that ships must maneuver through here in the States as well, with the Chelsea St. Bridge in Boston Harbor being a prime example. To get into the oil terminals in Revere, Ma. you must first go through the McArdle Bridge, with a 193-foot wide draw that cannot be fully utilized because of an 11-foot spot on the Chelsea side of the draw, and then make a moderately sharp left turn to line up for the ass-puckeringly tight 93-foot wide draw of the Chelsea St. Bridge. I’m talking loaded tankers here, not bulkers. But this is done at very slow speeds, with the ships generally using only short bursts of power from their propellers, letting the tugs do most of the steering through the last bend and the bridge. In this kind of situation the bow and stern tugs work very well and the risks are minimized because of the slow speeds involved, whether the tugs be conventional or tractor. This was going on for a long time before the tractors arrived on the scene, and I never saw or heard of anything unduly risky associated with this transit.

I’ll sum it all up with this: I’m all for learning as many different ways to skin the cat as I can. The more things I have hidden away in my bag of tricks the more likely I am to be able to improvise on the spot to get out of a jam on some dark and stormy night. But you better check yourself often, questioning your own practices without mercy, and searching for new ways to adapt them to different and changing circumstances. Complacency kills. This is the mental zone where lots of experience can actually work against you. If you get too slack at the wrong time then the cat may wind up skinning you instead.

If you haven’t read it already, please see Death on the River Clyde: a tug is tripped and three men are lost in Scotland for Part I of this story.

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Responses

  1. Good post, lots to think over. Keep up the good work.

    K.C.

  2. […] more on this subject check out Death On The River Clyde, More Thoughts On The River Clyde Tragedy…, Do You Live In A Barn?, and Getting Tripped: Roll The […]


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