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[rhavrane]

Bonjour,

When a 20 kilos radio-controlled steam tug (model boat) pulls a 450 kilos launch boat with a short rope, no problem, but when she pulls, takes a sharp turn and forgets the inertia of his burden ...

https://youtu.be/g-R29YkaoWI

For information, her machine is a steam Stuart D10.

[Martin (Admin)]

 
         

[likeomg]

Still happens today,


https://assets.publishing.service.gov.uk/media/67333270f407dcf2b5613525/2024-17-Biter-HebrideanPrincess.pdf

[Martin (Admin)]

I don't want to appear simplistic, uncaring or unsympathetic ....
 
   but what are some reasons why crew can't / don't escape .... from small boats / ships?

[likeomg]

From my experience -


Lack of training / familiarity i.e. touch drills / actual drills. They also more than likely entered a state of shock and one gent was in his 60's, one in his 70's.


I work on the largest pax ships in the world with a really strong safety culture but I do know a lot of ships out there are still completely still "the Wild West"


it's been a while since I read the full report.


Hopefully the new workboat code helps prevent this stuff.

[Colin Bishop]

The towing point on the tug appears to be well aft. Shouldn't the towing hook be nearer amidships to allow the tug to pivot if a sideways load comes on?

Colin

[Neil]

yes indeed, Colin. Absolutely correct, and usually attached to the aft end of the main superstructure

[JimG]

If you read the report posted it makes the point that if the tow rope is mounted to a hook nearer midships then a sideways pull can lead to the tug being pulled sideways without enough power from the drive to turn it. This leads to it being girted and possibly capsizing. That is why a gob rope is used to bring the position where the tow rope if held neare the stern so that a sideways force will pull the stern round and help the tug line up when towing in reverse.
Jim

[likeomg]

I think you gents have it the wrong way around... [/size]Having the tow point in the centre of the tug is the exact reason for the above incident I posted...I don't think they had the gob rope connected or it wasn't configured in a way that would help. Now I'm no expert on tug operations but did have to study the basics for my license so happy to be corrected..

[likeomg]

Jim replied while I was typing my response...


But yes, Jim is correct.

[Umi_Ryuzuki]

I read, that it was due to speed, and that the gob rope was misconfigured, or came loose, and
that it allowed the towing bridal to reach the midship, near the tow hook, and was then girted. 

Potential causes include: the samson post securing
arrangement, where the gob rope was wrapped 4 to 5 times around the post
before locking turns were applied, was inadequate; or that the locking turns were
inadvertently dislodged or lost during the manoeuvre.

 .

[Neil]

thank you Umi.

[Colin Bishop]

Just read the report and now have a better understanding of the forces involved etc.  It does look like the tug was making a  manoeuvre which required a very high degree of skill and that the speed of the tow was also a critical factor.

Colin

[likeomg]

bourbon dolphin is another good read...


For mates / masters stability there is a whole section on offshore supply boats, for my mates / masters stability exam it was one of my questions. luckily I had read up on a few bits and pieces prior to the exam as it's completely theory, no calcs.

[dodes]

Sometime since I played with tugs for a living, but towhook is always forward of a tugs pivot point, when in the bow towing must always have the strain and keeping a careful watch that you do not come off the bow of the tow, if you do and cannot reach back to ahead , you knock out the tow to save yourself. Several ship handling tugs have capsize with loss of live because they could not knock off the tow. A gob rope is used when you was a stern drag position so that the tug cannot be girted when being towed backwards by the tow. Since late sixties all ship handling tugs have a pneumatic operating system to release the hook in the wheel house, before that a senior rate would standby with a maul or axe to release the hook/tow.

[dodes]

Correction to last the pivot of a tow hook is in the tugs pivot point about 1/3rd from the bow.

[1967Brutus]

I don't want to appear simplistic, uncaring or unsympathetic ....
 
   but what are some reasons why crew can't / don't escape .... from small boats / ships?

Most of the time, when fatal accidents happen, the fatalities are either because those persons are at a point of impact of sorts, OR because the smaller the boat, the more rapid the sequence of events that together cause/form the incident.
Some of the captains I sail with prefer me not doing any engineroom work as long as the towing line is tied to something, because of that, when doing harbour work. At sea engine room work is often unavoidable during towing.

As for towing over the stern, I am not that long working on tugboats, and have no experience with the older single prop tugboats that typically only are capable of towing over the stern, so I don't know much about gob ropes. I just recently learned that that is what the aft bit in the centreline of my tug is for

[1967Brutus]

Bonjour,

When a 20 kilos radio-controlled steam tug (model boat) pulls a 450 kilos launch boat with a short rope, no problem, but when she pulls, takes a sharp turn and forgets the inertia of his burden ...

https://youtu.be/g-R29YkaoWI

For information, her machine is a steam Stuart D10.

After watching the video: it is more than just the short towline and the inertia: it looks like you have a bridle on the tugboat, instead of on the tow. That combined with the high point of attachment on the tow, creates a much greater listing moment on the tug. You can see the tug listing very strongly every time you give a rudder command.
A single point of attachment on the tug (no transfer of moment), and a lower point of attachment on the tow would have reduced this significantly.

[1967Brutus]

After watching the video: it is more than just the short towline and the inertia: it looks like you have a bridle on the tugboat, instead of on the tow. That combined with the high point of attachment on the tow, creates a much greater listing moment on the tug. You can see the tug listing very strongly every time you give a rudder command.
A single point of attachment on the tug (no transfer of moment), and a lower point of attachment on the tow would have reduced this significantly.

But... Dang, that tug of yours is impressively powerful!

[rhavrane]

Bonjour,

I am a lucky collector because I have several powerful tugs and I just sunk one    Most of them have a Stuart D10 :

The Jan sunken inside : https://youtu.be/utYZJDJPBVg

The Côte d'Emeraude (the tug that gave me the steam virus ): https://youtu.be/tSOSj89BY_M

The Ulysse Max : https://youtu.be/JdRwDXVLJIA

And with a brother of the D10, the Reeves Warrior MK3 in Moulay-Idris : https://youtu.be/6SLqSuZjE94 and there I remembered my mistake : https://youtu.be/kJptRVqmt8k

Besides this, an only  5 cc tug can also be powerful, Here is Paterson  : https://youtu.be/9hN4i6FjPfw