I figure that most cruising sailboats, even those keeping a good lookout
won't spot a white superstructure at 9 miles but will probably spot a
hull at 5 or so miles.

The numbers I used were "best case" scenario straight from Bowditch.
The reality is that most sailors will likely spot a surface contact at
ranges more like what you've shown.

Nobody in the commercial fleet runs at 32-36 knots, especially not
tankers! The very fastest container ships and LNG carriers are around
25-27 knots. Cruise ships are slower, around 22-23 knots top speed and
most tankers are slower still. The exception would have to be the SL-7
Fast Sealift ships which did 33 knots on trials.

I didn't mean to imply that -all- big ships operate at speeds over 30
knots, I was trying to make a point in reply to the original posters
question and some of the misconceived replies, ie. "at least an hour
will pass from when I see a contact on the horizon to when it will hit
me". My point is that ships at sea operate at a wide variety of speeds,
even in excess of 30+ knots, and as a cruiser you need to be aware of
this. As for "high speed" ships out there, I think you guys are off on
this. All the newer ships are being built to operate at 30 knots or
greater. There are a number of "fast" container and oil carrier ships in
the works, and shipbuilders are starting to deliver "fast" ferries that
will operate at 40+ knots. And it won't stop there, I've read that the
designers have plans for ships that will operate at 50 to 60 knots.

See my post above. I think a lot of flag of convenience ships don't
have their radar on all the time, probably to save the cost of replacing
the magnetron.

That's not been my experience at all, but you're welcome to believe what
you want.

--

=-------------------------------------------------=
Renewontime
A FREE email reminder service for licensed mariners
http://www.renewontime.com
=-------------------------------------------------=

Could you tell us what is a sufficient RADAR target?

I'm afraid I can't give you any substantive help shopping for a RADAR
reflector. There was a long thread on this a couple of weeks ago that
might be helpful.

They say that in my area many commercial ships from a certain country do
not really keep RADAR watch, only listen to a possible radar warning
while reading magazines and having tea. Does that seem possible?

Possible? Anything is possible, but as I've posted earlier, that has
not been my experience. There have been exceptions though, as I posted
earlier.

Where would you like the yachts to have their navigation lights?
Masthead or deck level? Masthead is seen from further away, but misleads
with regard to distance.

By all means, I'd rig the biggest, brightest navigation lights you can
either at the masthead (tri-color if the size of your yacht allows it)
or the "red over green" additional lights on your mast. More
information on the proper location of these lights can be found in COLREGS.

--

=-------------------------------------------------=
Renewontime
A FREE email reminder service for licensed mariners
http://www.renewontime.com
=-------------------------------------------------=

I missed this one:

Not in my experience. I've often called up passing merchant vessels at
sea on VHF 16 and it usually takes several calls for about 10 minutes
before _some_ will reply. I've asked how my visibility on radar is and
got the reply: "let me warm it up....".

I won't try to make excuses for how others may stand their watch (and
yes, I've got my share of similar stories), but would only suggest that
there are other possible reasons for why you aren't getting responses to
your hails on 16, including the possibility that they did not receive
your hail, the watch officer didn't speak English, or that they decided
it wasn't necessary to respond.

--

=-------------------------------------------------=
Renewontime
A FREE email reminder service for licensed mariners
http://www.renewontime.com
=-------------------------------------------------=

Dag Stenberg wrote:
In rec.boats.cruising renewontime dot com wrote:

The problem for merchant ships is that small sailing vessels are just
hard to see. VERY hard to see. They usually present a poor RADAR
target and have dim or no navigation lights.


Could you tell us what is a sufficient RADAR target?
I found an old article:
http://www.ussailing.org/safety/Stud...eflector_2.htm
according to which my Mobri "does not perform well".

They say that in my area many commercial ships from a certain country do
not really keep RADAR watch, only listen to a possible radar warning
while reading magazines and having tea. Does that seem possible?

To get a radar warning alarm, they would need to have the radar turned
on and operating. However, if you are asking if someone is standing by
the radar at all times watching it, the answer is, no.


Where would you like the yachts to have their navigation lights?
Masthead or deck level? Masthead is seen from further away, but misleads
with regard to distance.

Dag Stenberg

Where the rules allow, the higher the better. Don't worry about them
misleading as to distance as much as worrying about being seen at a
distance.
A great secondary ID method for sailboats at night is lighting up your
sails with a flashlight, etc..
Generally this will give a brighter target without destroying visibility
of your running lights.

otn

"Evan Gatehouse" wrote in message news:

Third, it's been my experience (30+ years at sea) that almost every
merchant vessel at sea maintains a -very good- watch and lookout. There

Not in my experience. I've often called up passing merchant vessels at
sea on VHF 16 and it usually takes several calls for about 10 minutes
before _some_ will reply. I've asked how my visibility on radar is and
got the reply: "let me warm it up....".

Couple points here to keep in mind.
On most ships, English is not the "first" language and the quality of
"English" lessens as you go from Master to 3rd Mate.
If you run across a ship that doesn't have at least one radar running,
normally you will find that they will be on standby, which means no
"warm-up" needed. However, depending on the set, there's a good chance that
the set itself will not be set on a range where you will be seen if you are
close (at sea range, 12 or 24 mi.) so adjustments will be, or may be
needed.
Also, keep in mind that depending on the radar in use (10cm or 3cm) in some
conditions you may not be visible at all due to sea return or age and
condition of the set, plus the particular operators abilities.
Radar is no more foolproof than anything else, so just because one ship says
he has no problem or a great problem seeing you, doesn't mean ALL will have
the same results, even under the same conditions.


otn

Steve Firth wrote:


Correct, the Mobri has always done badly it plain doesn't work. IIRC
when studies were done of the Mobri at Fort Cumberland they actually
reduced the radar cross section of the yacht compared to having no
reflector.

clearly a "stealth" technology then, best avoid the US 6th fleet or they
will shoot on sight.


--
Lithium ion internal and external batteries.
Internal from £30 External from £75 (trade)
All batteries factory new and guaranteed.
http://www.surfbaud.co.uk/
e-mail (www.rot13.com)

"renewontime dot com" wrote in message news:

I didn't mean to imply that -all- big ships operate at speeds over 30
knots, I was trying to make a point in reply to the original posters
question and some of the misconceived replies, ie. "at least an hour will
pass from when I see a contact on the horizon to when it will hit me". My
point is that ships at sea operate at a wide variety of speeds, even in
excess of 30+ knots, and as a cruiser you need to be aware of this.

Very true

As for "high speed" ships out there, I think you guys are off on
this. All the newer ships are being built to operate at 30 knots or
greater. There are a number of "fast" container and oil carrier ships in
the works, and shipbuilders are starting to deliver "fast" ferries that
will operate at 40+ knots. And it won't stop there, I've read that the
designers have plans for ships that will operate at 50 to 60 knots.

The number of ships of any type running at 30+K is small and will remain so
for some time. Biggest problem becomes HP to get them to that speed versus
fuel consumption. (one reason the the previously mentioned SL-7"s are now
all US Gov.... they're the only ones who can afford or justify running
them).
High speed ferries, on the other hand, running in the high 30's are becoming
"a dime a dozen".
Newer technologies, as you say, are on the drawing boards.

See my post above. I think a lot of flag of convenience ships don't
have their radar on all the time, probably to save the cost of replacing
the magnetron.

That's not been my experience at all, but you're welcome to believe what
you want.

G I'm probably in between both of you on this.
First off, the problem is less "flag of convenience" and more "owner,
operator".
Since ships all have at least 2 radars, both of which are at least on
"standby" at sea (exceptions noted), coupled with ever increasing
enforcement and penalties for non use, the old "magnetron" excuse is falling
by the wayside.
However, it's not a perfect world and there are still too many fools out
there running with radars turned off in open ocean conditions.

otn

In rec.boats.cruising Steve Firth wrote:
The best on test was the Firdell Blipper.

Not in the 1995 test ( http://www.ussailing.org/safety/Stud...eflector_2.htm)

Dag Stenberg

I did like the scale used for measuring the return from "radar flag", though
I can't recall
it as an ISO measurement from my days as a student.

Presumably the scale runs

Coot, Duck, Swan, Albatross, Dumbo...

And accounts for the saying

"Less chance than a duck in the fog"

Could you tell us what is a sufficient RADAR target?
I found an old article:
http://www.ussailing.org/safety/Stud...eflector_2.htm
according to which my Mobri "does not perform well".

renewontime dot com wrote:
snip
I didn't mean to imply that -all- big ships operate at speeds over 30
knots, I was trying to make a point in reply to the original posters
question and some of the misconceived replies, ie. "at least an hour
will pass from when I see a contact on the horizon to when it will hit
me". My point is that ships at sea operate at a wide variety of speeds,
even in excess of 30+ knots, and as a cruiser you need to be aware of
this. As for "high speed" ships out there, I think you guys are off on
this. All the newer ships are being built to operate at 30 knots or
greater. There are a number of "fast" container and oil carrier ships in
the works, and shipbuilders are starting to deliver "fast" ferries that
will operate at 40+ knots. And it won't stop there, I've read that the
designers have plans for ships that will operate at 50 to 60 knots.


Fascinating. I'd like to learn more - can you point me at any web
sites? I can't find anything much over 25kts.

Thanks

Andy.