....
Sitting at the nav station typing 500 word posts and looking at a
RADAR screen every 15 min violates COLREG RULE 5. Get out of the
office and sail your boat!

Yes but just about all vessels that go off shore are in violation of
rule 5 most of the time. As nearly as I can make out fishing vessels
never keep any watch at all, but even commercial carriers are pretty
bad about watch keeping at sea. The "good news" for small boat
operators is that it is unlikely that we will damage the vessel that
runs us down so if we don't keep a good watch we probably aren't
endangering anyone but ourselves. Still, I'm not totally in love
with Skip's watch keeping system. Leaving the RADAR on 24 miles is a
mistake. Most targets will not show at 24 miles and closer targets
may be lost in the clutter. Also intermittent targets will only be
evident if you watch the ppi closely for several scans. Good practice
when only one set is available is to watch the screen for several
scans at long range and then repeat at medium and then short range
periodically. It is also very important to make a careful visual
scan on a regular basis. In clear weather I've found that we almost
always make visual contact on small targets before we see them on
RADAR.

-- Tom.

" wrote in
oups.com:

...
Sitting at the nav station typing 500 word posts and looking at a
RADAR screen every 15 min violates COLREG RULE 5. Get out of the
office and sail your boat!

Yes but just about all vessels that go off shore are in violation of
rule 5 most of the time.

Neither agree or disagree

As nearly as I can make out fishing vessels
never keep any watch at all, but even commercial carriers are pretty
bad about watch keeping at sea.

Based on what first hand knowledge?

The "good news" for small boat
operators is that it is unlikely that we will damage the vessel that
runs us down so if we don't keep a good watch we probably aren't
endangering anyone but ourselves. Still, I'm not totally in love
with Skip's watch keeping system. Leaving the RADAR on 24 miles is a
mistake.

Yes and no..... for ships, one set on 24, one on 12 with occasional
shifts down is great.... offshore for small boats, leave it on 12 ( you
should still see any closer targets if you know how to use the radar)
with occasional shifts down in reduced vis.

Most targets will not show at 24 miles and closer targets
may be lost in the clutter. Also intermittent targets will only be
evident if you watch the ppi closely for several scans.

Again, yes and no.... depends on your system....etc.

Good practice
when only one set is available is to watch the screen for several
scans at long range and then repeat at medium and then short range
periodically. It is also very important to make a careful visual
scan on a regular basis.


Nothing wrong with this.

In clear weather I've found that we almost
always make visual contact on small targets before we see them on
RADAR.


G Again, depends on your system


otn

On Aug 11, 3:43 pm, otnmbrd wrote:
" wrote groups.com:
....

OTNM, you raise good points, and I've made some sweeping statements
and moved freely between Skip's particular case and cases in general.
Also, I get the feeling we may be talking about different conditions.
My experience has largely been in international waters far offshore
and may not really apply to more typical near coastal conditions.
Anyway, with that in mind:

[] As nearly as I can make out fishing vessels
never keep any watch at all, but even commercial carriers are pretty
bad about watch keeping at sea.

Based on what first hand knowledge?

I read the incident reports in the backs of the trade mags. I also
have friends in the marine trades and merchant marine and friends who
make their living as fisheries observers and friends who are serious
small boat voyagers. They all tell tales. I've also worked for a US
shipping company, but in IT and all I can attest to from that is that
some ship's officers in US domestic trade spend a lot of time reading
and creating reports while at sea. For the last year or so I've been
working out of my pilot house and have had a VHF monitoring most of
bridge to bridge traffic in the Honolulu area and I'd guess that as
much as a third of all attempts to get passing agreements fail because
one party isn't keeping watch (the navy is particularly inept at
this). But that's all second hand. My first hand knowledge is in
small boats so I can't report on what is actually happening on the
bridges except when we pass close enough to see into them, but I can
report on what seems to be happening from the small boat operator's
point of view. I've spent a good deal of time offshore doing delivery
work, racing and six years of full time long distance cruising that
included three circuits of the pacific and it has become my custom to
hail most contacts on the VHF when offshore. My feeling from this
unscientific survey is that even of those vessels professional enough
to keep a radio watch few if any keep a continuous and careful visual
and radar watch when off soundings.
....
Leaving the RADAR on 24 miles is a
mistake.

Yes and no..... for ships, one set on 24, one on 12 with occasional
shifts down is great.... offshore for small boats, leave it on 12 ( you
should still see any closer targets if you know how to use the radar)
with occasional shifts down in reduced vis.

I agree that 12 is the best compromise for most small boats and small
radars offshore, but you should change scales regularly. It has been
years since I took my radar training and technology has improved but I
recall that continuous long range scanning was considered very bad
form (maybe even illegal in the context of watch keeping). Even if
the new digital sets have made this better it is still going to be
easier to see small, close targets on the closer scales at the very
least because they will be bigger blobs on the ppi.

....
[] Most targets will not show at 24 miles and closer targets
may be lost in the clutter. Also intermittent targets will only be
evident if you watch the ppi closely for several scans.

Again, yes and no.... depends on your system....etc.
....
[] In clear weather I've found that we almost
always make visual contact on small targets before we see them on
RADAR.

G Again, depends on your system

True. The context I was thinking of when I wrote those comments was
offshore using a small, unstabilized, analogue radar of the type
typically fitted to yachts.

-- Tom.

On Sat, 11 Aug 2007 18:16:59 -0700, "
wrote:

In clear weather I've found that we almost
always make visual contact on small targets before we see them on
RADAR.

If so, I'd argue that you need a better radar. We usually pick up
small fiberglass boats in the mid 20 ft range at around 4 miles on the
radar and I often need binoculars to find them visually unless they
are under sail. Our radar is a 3 year old Furuno with a 4 kw dome
scanner about 25 feet off the water. Getting gain and sea clutter
properly adjusted is one of the keys to good performance. I also like
the electronic averaging function which combines multiple scans to
enhance the image.

On Aug 11, 9:57 pm, Wayne.B wrote:
On Sat, 11 Aug 2007 18:16:59 -0700, "

. We usually pick up
small fiberglass boats in the mid 20 ft range at around 4 miles on the
radar and I often need binoculars to find them visually unless they
are under sail.


Any of those mid 20s foot boats have wood masts????
Stealthy Bob

On Aug 11, 6:57 pm, Wayne.B wrote:
On Sat, 11 Aug 2007 18:16:59 -0700, "

wrote:
....
[we] make visual contact on small targets before we see them on
RADAR.

If so, I'd argue that you need a better radar. ...

Yeah, there is better radar out there. For some reason I was thinking
about offshore work rather than coastal. Even with our nasty 4kw
Raymarine mono lcd set we can see tiny targets in glassy conditions.
Given a couple meters of swell little boats get lost in the clutter.
However, in good vis, particularly at night, we can see them or their
lights with our eyes when they are weak and intermittent targets on
the radar.

-- Tom.