The wet tow of the Polar Pioneer was exiting Admiralty Inlet entering the Strait of Juan de Fuca, when all of a sudden there was a frenzy of activity involving overtaking or passing vessels. It was quite remarkable to witness!
Like motor vehicle laws, there is a set of International Regulations for Preventing Collisions at Sea - known as ColRegs. ColRegs establish rules and regulations for operating vessels in a safe responsible manner, enabling mariners to have reasonable expectations about how other captains and crews will react in specific situations.
"ColReg Rule 13 governs overtaking situations and states that, "any vessel overtaking any other shall keep out of the way of the vessel being overtaken." This rule applies to all vessels, not just power-driven vessels, as is the case in crossing and head-on situations. The rule does not require the overtaking vessel to maneuver in any particular manner, generally allowing an overtaking vessel to pass on either side of the overtaken vessel. However, care should be exercised by the overtaking vessel to maintain an appropriate distance off the overtaken vessel to prevent the effects of interaction, as well as to ensure that it is well clear of the overtaken vessel before any subsequent alteration of course ahead of the overtaken vessel.
"Furthermore, Rule 13(b) states that, "a vessel shall be deemed to be overtaking when coming up with another vessel from a direction more than 22.5 degrees abaft her beam," such that only that overtaken vessel's stern light and neither of its sidelights would be visible at night. Thus, there are clear tests that can be employed, which are intended to eliminate any doubt as to whether a vessel is overtaking or crossing. A vessel may employ the use of radar and automatic radar plotting aids to determine its relative position and angle of approach, as well as observe the lights of other vessels. Despite these efforts at providing a bright line test for determining one's status, there are certain factors, such as the failure to track a vessel on radar or the range at which lights may become visible and identified, which may lead to uncertainty.
"However, Rule 13(c) attempts to resolve any uncertainty as to the status of an overtaking vessel by stating that, "when a vessel is in any doubt as to whether she is overtaking another, she shall assume that this is the case and act accordingly." Finally, Rule 13(d) states that, "any subsequent alteration of the bearing between the two vessels shall not make the overtaking vessel a crossing vessel within the meaning of these Rules or relieve her of the duty of keeping clear of the overtaken vessel until she is finally past and clear.
"Rule 13(d) is intended to resolve the starboard quarter approach problem. Whereas a vessel coming up on another vessel's port quarter would be the give-way vessel regardless of whether it is an overtaking or crossing situation, the same cannot be said for the starboard quarter approach, where the vessel coming up would be the give-way vessel in an overtaking situation and the stand-on vessel in a crossing situation."
"Finally, Rule 13(d) is intended to prevent such a shift in status by prohibiting an overtaking vessel, by virtue of a change in its position relative to the overtaken vessel, from becoming a crossing vessel once it is less than 22.5 degrees abaft of its beam or in such a position as to see its running light and masthead light(s) and not its stern light."
That's the long version of ColReg 13 concerning overtaking situations. The short version is much easier to digest:
The semi-submersible Transocean Polar Pioneer finally shoved off from Terminal 5 in Seattle Monday morning, immediately getting tangled up with anti-Shell (Shell-No) kayaks. There is much angst about Royal Dutch Shell ruining the Chukchi and Beaufort Seas.
She was pulled out by two Foss Maritime tugs, with a third Foss tug, Garth, in the "braking" position. Having covered only a few miles, the convoy went into a convulsion, captured by MarineTraffic AIS tracking.
For reasons unclear to the casual observer, the two lead Foss Tugs, switched the tow over to two Crowley tugs, the Ocean Wave and Ocean Wind, with the Garth Foss remaining in the rear "braking" position.
Finally the tow headed up the Salish Sea. I calculated they would pass me here in Port Townsend around 7 or 8 p.m. I have two view points to consider, Marrow Stone Island or Point Wilson. Having wasted a fifty mile round trip earlier in the day when I thought the tow would pass, not realizing the towline switch was the reason I sat empty handed, I elected to go out to Point Wilson.
Turned out I should have returned to Marrowstone Island. That's it to the right in this shot. I am just over 5 miles from the tow, a distance that could have been cut by more than half, had I returned to Marrowstone Point.
Rule 13 Madness
The shot distance finally decreased to about 2 miles by the time this frenetic "overtaking" - passing - situation took place, involving multiple vessels and tows. According to the AIS (Automatic Identification System) readings, "the tow," consisting of the Ocean Wave, Ocean Wind, Polar Pioneer, with Garth Foss,
escorted by the 87 foot (26 meter) Marine Protector Coastal Patrol Boat USCG Blue Shark, making 5.6 knots (6.4 mph.).
The first overtaking situation occurred when Oceania Cruises "Regatta" enroute from Seattle to Alaska, making 12.4 knots (14.2 mph), caught up with the tow. In accordance with ColReg Rule 13, engaged in a port-starboard passing, passing on the left side of the tow.
At the far side of the tow, we can barely make out another tug and barge, passing the tow port-starboard, the Seaspan King with her tow, heading to Vancouver B.C. Oh, yeah, just for good measure, the high speed catamaran Victoria Clipper, whizzed by all opposing traffic, heading for Seattle on her second round trip of the day.
All of this action took place in 10 to 15 minutes, just after 8 p.m.
Where Are They Now?
In the middle of the night, the tow (Polar Pioneer) did yet another maneuver off Port Angeles, dropping off both the Puget Sound Pilot, and the Garth Foss. This afternoon (Tuesday), the tow, joined by Shell's Anchor Handling Tug Tor Viking II are clearing the Strait of Juan de Fuca, all heading toward Dutch Harbor.
The Regatta is well into her journey up the Inside Passage. The HS Chopin is heading for China, the Island Scout is alongside in Nanaimo, and the Seaspan King is alongside in Vancouver B.C.
1 Comments - Click here:
what awesome entertainment! The modern dance of the tow masters, cruise ship viewing, commerce at it's best and the Victoria Clipper for the added touch of color. As usual the wonderful pictures and explanations. Thanks for it all.
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