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hello,
any thoughts on ships with z-drives or multiple thrusters that can move in a
straight line in any direction?  Is this a case where the "bow" could be any
point on the ships hull?  Also, someone mentioned rule 34 concerning sound
signals when operation astern propulsion. . .how does this rule apply to
z-drives etc.?
QM2 Brent Ferrantelli. USCG
----------
>From: captainmike7@XXX.XXX
>To: <navigation@XXX.XXX>
>Subject: Re: [Nml] Rules of the Road While Backing
>Date: Sat, Feb 1999, 2:58 AM
>
> At 20:34 2/5/99 -0800, Dennis W. Farrell wrote in part:
>
>>It is the practice of seamen to consider in such cases that the rules
> apply with >reference to the direction of motion of the ship so that for
> the time being, the >starboard side becomes the port side and the port side
> the starboard side.
>>In other words, we must consider the pilot of a backing vessel to be
> facing aft >toward the direction in which his ship is moving.  He must then
> keep clear of a >vessel on his right hand as if that were his starboard
> side.  And his whistle signals >must correspond.
> ______________________________________________________________
>
> What, then, is the significance of Rule 34, which requires power-driven
> vessels when meeting or crossing to sound three short blasts to mean "I am
> operating astern propulsion"?  Surely not just to advise vessels off her
> bows that she is backing AWAY from them?
>
> This "direction-of-travel" interpretation is at odds with Rule 13(a):
> "NOTWITHSTANDING ANYTHING contained in the rules of Part B, Sections I and
> II, any vessel overtaking any other shall keep out of the way of the vessel
> being overtaken" and 13(b) "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 (i.e. 67.5 degrees either side of dead astern)...that is, in such
> a position with reference to the vessel she is overtaking, that at night
> she would be able to see only the sternlight of that vessel but neither of
> her sidelights."  Note that there is no reference to direction of travel in
> the "Overtaking" rule.  Under the "direction of travel" interpretation,
> must the vessel backing at night also relocate her sidelights and
> sternlight?  How else would other vessels know to treat her stern as her
> bow?  Relative motion can be difficult to interpret in the dark.
>
> I don't even want to BEGIN thinking about the situation where BOTH vessels
> are backing toward one another at night, each at 65 degrees to the other's
> stern.  Who's overtaking whom?
>
> (It is worth noting that vessels making a habit of not turning around when
> going back where they came from - primarily double-ended ferries -
> generally have machinery and propellers at each end, so they do not operate
> "astern propulsion".  They also reverse their navigation lights to
> accommodate direction of travel).
>
> P/Lt/C Michael A. LeButt, FC
> Balboa (Newport Beach, CA) Squadron
>
> "A ship in harbor is safe,
>   but that's not what ships are for..."
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