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Arcb 11-03-2017 06:10 PM

Re: Towing and being towed
 
Quote:

Originally Posted by Minnesail (Post 2051270434)

How long is "quite long"? 200 feet? 2,000 feet?

I think a well managed tow will be somewhat dynamic in nature, not a set it and forget it type of thing. Assuming a long tow for covering ground on open water; factors that may need consideration include weight and drag of the towed vessel as well as wind and sea state, as well as weight and construction of the tow line.

I think the goal is to have sufficient catenary. If there is enough catenary in the tow line, the weight of the tow line should work as a shock absorber, So however much line that requires in the current conditions. Plus, as mentioned by RichH, I think it would be a good idea if you were to sync with the length of the tow line with the wave period to reduce shock loads, and to not pull your buddy through a wave (which he may not appreciate).

The other consideration might be to bury the catenary below the surface of the water to reduce the impact of recoil if the line parts, the water might take some of the zing out of things.

A big consideration, especially if the tow is bigger than the vessel doing the towing which is often the case, is you want them far enough back that the towed vessel does not over take and GIRD the towing vessel. Girding is probably the biggest single risk in a towing operation. Basically, it happens when the tow overtakes, and side loads the tow line on the towing vessel (which is ideally attached forward of the rudder post, as Fast explained earlier with dinks). When the towed vessel over takes, it flips the towing vessel and possibly runs it over. Bad. Very bad. This is a big concern with following wind, sea or current, but should always be a consideration. You might want the towed vessel back far enough that you KNOW you can cut the line before the tow can over take you.

Go out and practice with your friends. It will be fun, just make sure you have enough fenders if you are doing a hip tow. Play with different tow lengths and observe. Look listen feel. I think a well set tow line will feel like a well set tow line.

Arcb 11-03-2017 07:12 PM

Re: Towing and being towed
 
Apologize for posting twice in a row, but I thought of something that might be useful.

There are a couple of hand signals that might be universally recognized by sailors, whether they be Taiwanese fishermen, USN or your local tow boat company.

If you want less tow line, make a fist with your index finger pointed towards the sky. Make a circular motion with your index finger, this will indicate less tow line. Make the same gesture, but with the index finger pointed down and this will indicate you request more tow line. Hold your hand open, then close it in a tight fist, and this will indicate you are happy with the amount of tow line. If you want your buddy to cleat off a tow, you could make a syimbol with two close fists, where you cross your arms just towards the elbow from the wrists.

RichH 11-03-2017 10:42 PM

Re: Towing and being towed
 
"Girding" is especially dangerous. The last 'girding disaster' on the C&D Canal about 15 or more years ago involved girding of a large tow and a towboat in the canal during 'rough weather' and adverse contrary tidal flow which caused the deaths of several on a tug towing a large barge which somehow overtook the tow during tight turn at night in the channel at the western side of the canal as it enters the Chesapeake @ Sandy Point/Herring Creek. The barge's tow line 'girded' the tow boat caused her to turn @ ~90 and which caused the tugboat to swamp, then capsize then partly sink ... with the loss of life to several of her crew. The moral of that story was to keep a sharp axe/hatchet ready to instantly cut the tow line when things get wild, out of control and dicey.

One of the most spectacular 'girding' episodes along the mid-Atlantic coast happened in the 'old' (infamous) Barnegat Inlet on the NJ coast in the late 1960s(?) with a tow boat attempting to enter the inlet with a tow during extremely adverse conditions, got 'girded' and which wound up capsizing and totally inverting the towboat, some of the crew never found. The word 'girding' still sends chills up and down my spine, many years after that incident and actually seeing that ocean-going tug swamped and upside down the following day in the (notorious, 'old') Barnegat Inlet.

Rx: you better 'really' know what the hell you're doing when towing, especially in 'blammo' sea state conditions. My hat's definitely off in admiration to those who do this.

Capt Len 11-04-2017 01:57 AM

Re: Towing and being towed
 
Try you tube. Tug capsizes off BC coast.

Arcb 11-05-2017 01:40 PM

Re: Towing and being towed
 
Found some more details on the Taiwanese fishing vessel that gave them a tow. Not surprisingly, the original details didn't really match up with reality.

The ship was a fairly large, modern Tuna Long Liner. 500 Gross Tons and 183 feet in length with a crew of 36.

The Taiwanese Captains account of the incident is they responded to the women in distress, offered to bring them on board, offered them food and water, however the women supposedly requested a tow to wake island. The fishing Captain agreed and towed them for 24 hours, or at least over night. Who knows what kind of a tow it was, might have been a bit like a pit bull trying to shake off a nasty flea.

Any way, the next morning the women changed their mind about the tow and requested use of the ships sat phone, which the Captain agreed to. The women got in touch with the navy. That sounds like a more believable account of the incident to me.

The Fong Chun No 66.

https://www.wcpfc.int/node/15454

hellosailor 11-05-2017 02:40 PM

Re: Towing and being towed
 
Last I'd heard of, Wake Island was a USAF "Keep off, or we'll shoot you!" installation. Cruisers not welcome, tourists not welcome, vessels in distress not likely to find much succor either.

Which all goes to back up my theory these two women are North Korean spies. First they try to use the "babes in distress" card, cultivated by months at sea, to get into a restricted USAF base that could be used in the demolition of North Korea. And when that doesn't work out, they try to take over a USN vessel.

All makes sense to me. I think I'll call the two "Pinky and the Brain".

Capt Len 11-05-2017 04:05 PM

Re: Towing and being towed
 
I once picked up a disabled 36' fishboat anchored south of James Island. Wind SE 25 and rising. We went back to Sidney. Only had the main up but for the tow it must have been disconcerting. Josh Slocum tells a tale of being towed(Liberdade) Big boats don't experience going over hull speed very often so don't see a problem.

chip 11-05-2017 08:50 PM

Re: Towing and being towed
 
I don't know anything about ocean or long-distance towing, but I had to get towed once for about 3 hours on the inside and didn't enjoy it very much. I was in my Catalina 22. The engine quit, and I had to go ~20 miles through a narrow channel with 20kts of wind on the nose. The first tow boat's engine also died before he could hook up with us, and he drifted off the visible horizon. The second boat was a big (for here) diesel inboard with elaborate towing rig. They threw us a bridal with two attachment points, which I connected to the two bow cleats. They then proceeded to tow us at 7 or 8 knots into the wind and waves, which the boat didn't like doing. We tried to lash the tiller and get out of the incessant spray, but we were still swinging a lot, and I wound up hand steering to keep us centered in the tow boat's wake. They knew what they were doing and were in constant communication over VHF and hand signals, extending and shortening the line to try to get us to ride smoothly. They got us there in one piece, but I couldn't imagine trying to do it for hundreds of miles in ocean swell several knots above my hull speed.

https://sailingfortuitous.com/beach-haven-cruise-2012/

https://sailingfortuitous.com/wp-con...2_05_26_29.jpg

fallard 11-07-2017 10:29 AM

Re: Towing and being towed
 
1 Attachment(s)
We were towed into Cuttyhunk about 6 years ago. The SeaTow operator used a tow line with an bridle at our end, attached to the two bow cleats, as shown in the thumbnail. I wasn't aware that the anchor would interfere when the bridle was attached when slack, but this would be an issue for a longer tow. Better to remove a bow anchor to be sure.

We were in frequent VHF communications, including the instruction to actively steer my boat to track behind the tow boat.

When we got to the harbor, the tow boat operator switched to a hip tow and greased us into an inside face dock as twilight was coming on. He was also helpful in lining us up with someone who picked up our replacement water pump pulley from the mainland and had it to us by noon the following morning. It was as close to an enjoyable experience as you could expect under the circumstances.

zedboy 11-07-2017 10:38 AM

Re: Towing and being towed
 
Quote:

Originally Posted by chip (Post 2051272770)
They then proceeded to tow us at 7 or 8 knots into the wind and waves, which the boat didn't like doing.

This to me is the key point: tell the guys in front, "SLOW DOWN!!!"

Your boat and its hardware will be happier to stay below hull speed. Trying to go faster will quickly stress things beyond their designed limits.


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