My seamanship question #2
 

"Jeff" wrote
| Let me say this again: The current has NO affect. If the boats were
| out of sight of land and had no GPS (or other such instruments) they
| would be unable to even detect the current. If there is a 20 knot
| wind from the North, and a 5 knot current running South, all the
| sailor knows is that there is a 15 knot breeze.


Oh fooey! This is getting hopeless..
Jeff, your just wrong! Your in irons. Your not going foward. The wind's
pushing you backwards. The sail is banging around in the middle of the boat.
If there's no current water will be going by you from back to front. The rudder
will work but opposite of how it usually works.
In this case there's a current going the same direction as the wind and
about the same speed. Your going backwards and the water is going backwards
at the same speed. The rudder has no motion through the water. It won't work.
I can't see why you keep talking about land. It's got nothing to do with
land. Only wind, current and water.


Cheers,
Ellen

My seamanship question #2
 

I'm wondering if it would have been better to stay with the sailboat, rather
than abandon ship... comments?

--
"j" ganz @@
www.sailnow.com

"Jeff" wrote in message
. ..
Baltimore Sun, 8/18/2001 - Sailing Trip Turns Treacherous.
Sailboat Meets 700-foot Tanker
One Mile North of the Bay Bridge in the Craighill Shipping Channel - A
couple tacking southbound at 3 a.m. in a 27-foot Catalina were unable to
get out of the way of a northbound 700-foot tanker loaded with 10 million
gallons of fuel. The wind had died & the sailboat's skipper broke the key
to the outboard motor and was unable to use the radio to effect. Before
the collision, the couple abandoned their boat, wearing life jackets &
carrying a whistle and rope (to avoid being separated.) The tanker brushed
past the sailboat. The couple were rescued after 2 hours and a search
effort by boats & helicopters from six federal, state and local rescue
teams. The tanker ran aground, briefly, but was refloated without damage
or loss of fuel. The sailboat remained operational and was returned to the
unhurt couple who sailed it to their destination.

My seamanship question #2
 

Ellen MacArthur wrote:
"Jeff" wrote
| Let me say this again: The current has NO affect. If the boats were
| out of sight of land and had no GPS (or other such instruments) they
| would be unable to even detect the current. If there is a 20 knot
| wind from the North, and a 5 knot current running South, all the
| sailor knows is that there is a 15 knot breeze.


Oh fooey! This is getting hopeless..

No, this is the most fun I've had since Jaxashby disappeared.


Jeff, your just wrong!
Oh No!

Your in irons.
OK

Your not going foward.
If there was a current I might never have been going forward. Think
about it.


The wind's pushing you backwards.

Backwards over the ground or through the water? If its over the
ground, how would I know? If its through the water, then the rudder
works!

The sail is banging around in the middle of the boat.
enough of the drama ...


If there's no current water will be going by you from back to front. The rudder
will work

Yes, I'm glad you understand this.

but opposite of how it usually works.

That depends how you look at it.

In this case there's a current going the same direction as the wind and
about the same speed.
Ahhh! We have a problem here. If the wind and the current is the
same speed and direction, then the boat (and all other boats in the
vicinity) feel no wind - it will effectively be flat calm, and the
alleged collision could not happen.

However, you stated there was both a strong wind and a strong current.
To my way of thinking, a strong current is between 3 and 6 knots,
beyond that would be extremely strong and only rarely encountered by
most sailors. However, a strong wind would be at least 15 knots, and
many would consider that pretty wimpy. If the "strong current" was 5
knots, and the "strong wind" was 20, this would be indistinguishable
from 15 knots of wind with no current.

Your going backwards and the water is going backwards
at the same speed. The rudder has no motion through the water.

No. This point is the identical to (and indistinguishable from) the
point where with no current, you stopped moving forwards. Immediately
following that, you start moving backwards, assuming the wind is
stronger than the current.

It won't work.
I can't see why you keep talking about land. It's got nothing to do with
land. Only wind, current and water.

It is only by looking at the land that you can tell there is a
current. If this concept illudes you, consider reading any physics
text written in the last 400 years, starting with Galileo's Theory of
Relativity.

My seamanship question #2
 

"Jeff" wrote
(lots of things that don't matter so I deleted them)

THIS is what matters and this is what happened in my question.
Your just being thick on purpose. Your wrong and I can prove it with an example.
In irons and the wind is pushing you backwards at 2 miles an hour over the bottom.
The current is going the same direction over the ground and at the same speed. 2 mph!
Your going backwards over the ground at 4 mph. Not through the water.
The boat has NO freaking motion through the water and the rudder won't work.
Duh! Forget about looking at the land. There doesn't have to be any land in sight
and you're still dead in the water.
Enough!

Cheers,
Ellen

My seamanship question #2
 

Jeff wrote:
.... If the wind and the current is the same
speed and direction, then the boat (and all other boats in the vicinity)
feel no wind - it will effectively be flat calm, and the alleged
collision could not happen.


Are you saying that if the wind and current are from the
same direction at the same speed, then boats could not
sail?!??!!

Think it over Jeff, a guy who is familiar with applying
Maxwell's equations... much less one with your experience...
ought to know the answer.

Fresh Breezes (and currents)- Doug King

My seamanship question #2
 

As I remember, the boat came through just fine.

Scotty


"Capt. JG" wrote in message
...
I'm wondering if it would have been better to stay with
the sailboat, rather
than abandon ship... comments?

--
"j" ganz @@
www.sailnow.com

"Jeff" wrote in message
. ..
Baltimore Sun, 8/18/2001 - Sailing Trip Turns
Treacherous.
Sailboat Meets 700-foot Tanker
One Mile North of the Bay Bridge in the Craighill
Shipping Channel - A
couple tacking southbound at 3 a.m. in a 27-foot
Catalina were unable to
get out of the way of a northbound 700-foot tanker
loaded with 10 million
gallons of fuel. The wind had died & the sailboat's
skipper broke the key
to the outboard motor and was unable to use the radio to
effect. Before
the collision, the couple abandoned their boat, wearing
life jackets &
carrying a whistle and rope (to avoid being separated.)
The tanker brushed
past the sailboat. The couple were rescued after 2 hours
and a search
effort by boats & helicopters from six federal, state
and local rescue
teams. The tanker ran aground, briefly, but was
refloated without damage
or loss of fuel. The sailboat remained operational and
was returned to the
unhurt couple who sailed it to their destination.

My seamanship question #2
 

"Ellen MacArthur" wrote



.
In irons and the wind is pushing you backwards at 2
miles an hour over the bottom.
The current is going the same direction over the ground
and at the same speed. 2 mph!
Your going backwards over the ground at 4 mph. Not
through the water.
The boat has NO freaking motion through the water and
the rudder won't work.
Duh! Forget about looking at the land. There doesn't have
to be any land in sight
and you're still dead in the water.
Enough!


If your boat is going backward at 4 MPH, and the current is
2 MPH ( that really should be in knots) then your rudder
should work just fine.

You're blond, aren't you?

Scotty

My seamanship question #2
 

DSK wrote:
Jeff wrote:
.... If the wind and the current is the same speed and direction,
then the boat (and all other boats in the vicinity) feel no wind - it
will effectively be flat calm, and the alleged collision could not
happen.


Are you saying that if the wind and current are from the same direction
at the same speed, then boats could not sail?!??!!

Think it over Jeff, a guy who is familiar with applying Maxwell's
equations... much less one with your experience... ought to know the
answer.

Fresh Breezes (and currents)- Doug King


Oh No! You've caused me to have Doubt!!!

Let's see - I'm sitting on my sailfish drifting south in a 2 knot
current. I blow a soap bubble and let it loose in a 2 knot true
breeze from the North. It drifts in the wind, headed south at 2 knots.
It sure seems like that soap bubble will sit over my boat. If the
apparent wind is not strong enough to blow a soap bubble into my sail,
I'd have to say I'm becalmed.

Let me try again. The true wind is 20 mph. I get in my XKE
convertible and drive 20 mph downwind. My daughter tries to fly a
kite from the passenger seat, but with zero apparent wind fails.

Again: I'm headed south to the Vineyard. Being a lazy SOB I'm
running both engines doing 8 knots. My wind indicator says zero knots
apparent. What's the true wind? What would happen if I raised sail
but kept the engines running? Why is this any different from being in
a southerly current?

What am I missing? (and I hope you're not referring back to the
kinetics discussion)

My seamanship question #2
 

Yes, the boat had no problem, the sailors were put back onboard and
they continued on.

Given my limited swimming ability, I would stay with the boat simple
because I doubt if I could get far enough away to improve my chances.
But I understand that many people have the fear that the boat will
get sucked under, and they along with it. I wonder if that really
happens?


Scotty wrote:
As I remember, the boat came through just fine.

Scotty


"Capt. JG" wrote in message
...
I'm wondering if it would have been better to stay with
the sailboat, rather
than abandon ship... comments?

--
"j" ganz @@
www.sailnow.com

"Jeff" wrote in message
. ..
Baltimore Sun, 8/18/2001 - Sailing Trip Turns
Treacherous.
Sailboat Meets 700-foot Tanker
One Mile North of the Bay Bridge in the Craighill
Shipping Channel - A
couple tacking southbound at 3 a.m. in a 27-foot
Catalina were unable to
get out of the way of a northbound 700-foot tanker
loaded with 10 million
gallons of fuel. The wind had died & the sailboat's
skipper broke the key
to the outboard motor and was unable to use the radio to
effect. Before
the collision, the couple abandoned their boat, wearing
life jackets &
carrying a whistle and rope (to avoid being separated.)
The tanker brushed
past the sailboat. The couple were rescued after 2 hours
and a search
effort by boats & helicopters from six federal, state
and local rescue
teams. The tanker ran aground, briefly, but was
refloated without damage
or loss of fuel. The sailboat remained operational and
was returned to the
unhurt couple who sailed it to their destination.

My seamanship question #2
 

Ellen MacArthur wrote:
"Jeff" wrote
(lots of things that don't matter so I deleted them)

I you have any intention of understanding how boats work, or how to do
basic navigation, you will have to learn this stuff.


THIS is what matters and this is what happened in my question.
Your just being thick on purpose. Your wrong and I can prove it with an example.

If I'm being thick (and its happened once or twice before) I'm
certainly not doing it on purpose.


In irons and the wind is pushing you backwards at 2 miles an hour over the bottom.
The current is going the same direction over the ground and at the same speed. 2 mph!
Your going backwards over the ground at 4 mph. Not through the water.
The boat has NO freaking motion through the water and the rudder won't work.

Hello?! If the boat is moving 4 mph over ground, but the current is
only 2 mph, then the boat must be moving 2 mph through the water!
Thus the rudder works.

I knew you'd come around to my way of thinking.

Duh! Forget about looking at the land. There doesn't have to be any land in sight
and you're still dead in the water.

Consider this: assuming the current and the wind have different
strengths (which is the original question) if you get into irons you
will start to slow down. Then you will be dead in the water. Then
you will start to go backwards. at this point your rudder works
again. There is no magic that says if there's a current you can't go
backwards through the water.

Consider also: you've been plopped in the ocean with no position
revealing instruments, but you do have speed and wind gauges. You
sail for some time and then get rescued. Your rescuers ask if you
encountered any current. What can you tell them?

Enough!

never!