Challenge: How do you solve this?

[David M]

Congrats Charlie! Your up to bat.

[Fishspearit]

Originally Posted by David M

Congrats Charlie! Your up to bat.

I think anyone can toss a question out there, it doesn't have to be the one who got the previous question. If so, then I apologize for stepping on your toes, David, because you got Pelagic's question.

[David M]

Not a problem...I didn't see it that way at all. Anyone who wants to submit the next question should probably do so? I will try to think up a question sometime soon so one of you go ahead.

[Dave the Canuck]

If the next person keeps the bikini model theme intact, I'd be most grateful.

[CharlieCobra]

Originally Posted by imagine2frolic

Charlie,

How does one get to be lucky enough to get caught in 5 hurricanes? Were you in the NAVY?

Yep but mine were all in Texas. Carla, Beulah, Celia, Allen and Alicia. I just happened to be where they hit, each and every time.

[CharlieCobra]

I'll throw an easy one out there.

You're on a 100 nm delivery of a new to you boat and the weather has turned from the forecasted 15-20 to 55+ and 12-15' wind waves. You're headed to a new home port that you've never navigated, night is falling and the GPS starts dieing. It turns out that the 12V outlet has no power and you've run the batteries down unknowingly. You have an absolute rookie and an ex Thistle racer as crew. You're halfway up the Admiralty Inlet and have recently left Useless Bay to Starboard. There's only the VHF's, a Depth meter and no other instruments. The wind is now up around 60 knots from the South and building. What do ya do?

[Lodesman]

Originally Posted by Fishspearit

There was no way to know what the storm's path was from the information that I gave, other than that it was passing to the south of us. That conclusion comes from the slight shift from NE wind to ENE. The shift being slight meaning that it would track pretty close to you, so continuing south would likely take you into it.

Yes - since your dastardly scenario removed any hope of a forecast, I considered the best solution was to rely on past history. Most of the tracked storms over the past 2 centuries follow one of 3 typical paths - they all form in the Atlantic E of the Leeward Islands then track W to the Caribbean. One path curves N before the Bahamas - since wind was NE, and veering, I discounted this as being likely. Another path is NW to the Gulf of Mexico - since the wind increased dramatically, I discounted it. The remaining "typical" path curves towards Florida, then N or NNE towards the Carolinas, which fit the symptoms, so I considered it most probable.

ENE would be a nice direction to go, but a tough one to sail since the wind was from that way. North to NNE would probably be the most comfortable and still away from the center. Hopefully, winds would continue to clock around as the storm passed, and you would be able to adjust your course clockwise as well.

Agreed absolutely - I was just presuming the winds would continue to veer, so a course as close to E as you can manage would be the best option. A good dollop of luck would be desirable, as well as a quick conversion - there are no atheists in a hurricane

Yep but mine were all in Texas. Carla, Beulah, Celia, Allen and Alicia. I just happened to be where they hit, each and every time.

Charlie - I think you should start a thread advising the forum on your location at all times - so we can know where not to be

[Lodesman]

Originally Posted by CharlieCobra

I'll throw an easy one out there.

You're on a 100 nm delivery of a new to you boat and the weather has turned from the forecasted 15-20 to 55+ and 12-15' wind waves. You're headed to a new home port that you've never navigated, night is falling and the GPS starts dieing. It turns out that the 12V outlet has no power and you've run the batteries down unknowingly. You have an absolute rookie and an ex Thistle racer as crew. You're halfway up the Admiralty Inlet and have recently left Useless Bay to Starboard. There's only the VHF's, a Depth meter and no other instruments. The wind is now up around 60 knots from the South and building. What do ya do?

Run into Port Townsend?

[CharlieCobra]

Told ya it was easy, which is exactly what we did. Turning and running to PT wasn't easy with the wind/seas on the beam and for some reason the waves really grew just off Pt. Wilson when we were dousing but we got 'r done.

next...

[Starbuck]

This is fun and educational, but if it's all going to be appended to one thread, things will grow ungainly after just a handful of challenges. If I wanted to scroll though seven pages just to find the place I wanted, I'd start a "Cruising and Guns" thread.

Seems to me that starting separate threads for each challenge would make much more sense. Each new scenario can then take its own shape without overlapping with others, etc., and there will not be an unmanageale 548-post thread to contend with.

The format for starting a thread would be simple:

What Would You Do?: Fog
What Would You Do?: Leaving the Bahamas
What Would You Do?: Daysailing with lubbers
What Would You Do?: Hit a Container

Now, I could be wrong, but this makes a lot of sense to me.

[David M]

"An ex-Thistle racer" ....For some reason that just sounded funny.

Ok...an easy one because it is one of my little pet peeves when people get the terms wrong....especially from some of these junior scientist grad students who I take out on the water who are supposed to know better.

Can the tide "come in" or "go out"?

Is there such a thing as a "flood tide"? or an "ebb tide"?

Can the tide ever rise as the current is ebbing? Can the difference between slack water and high tide be hours of difference or do they always occur at the same time?

What two causes could there be for a difference in both current velocity and direction between the top and the bottom of a river or estuary?

What might cause a vertical or diagonal current?

What is an ADCP? (bonus question)

Ok, some of these questions relate to physical oceanography, but then, being a good skipper means knowing some oceanography anyways.

[CharlieCobra]

His entire repertoire of sailing consisted of racing a Thistle on lake Erie, no keelboat/big boat experience at all.

[Pelagic]

Originally Posted by David M

"An ex-Thistle racer" ....For some reason that just sounded funny.

Ok...an easy one because it is one of my little pet peeves when people get the terms wrong....especially from some of these junior scientist grad students who I take out on the water who are supposed to know better.

Can the tide "come in" or "go out"?
No it Rises and Falls

Is there such a thing as a "flood tide"? or an "ebb tide"?

No you are talking about current in a prescribed direction in confined waters

Can the tide ever rise as the current is ebbing? Can the difference between slack water and high tide be hours of difference or do they always occur at the same time?

Yes! other elements like wind and excessive rainfall can cause a diferrence from the astronomical prediction

What two causes could there be for a difference in both current velocity and direction between the top and the bottom of a river or estuary?

Wind and Rainfall as the difference in SG of Fresh and salt water causes a layored effect acting independantly

What might cause a vertical or diagonal current?

Thermal upwellings

What is an ADCP? (bonus question)

Acoustic Doppler Current (predictions?)....I once did a 3 month job in the Columbia River after Mt St Helens blew positioning that equipment to measure changes in the rivers flow

Ok, some of these questions relate to physical oceanography, but then, being a good skipper means knowing some oceanography anyways.

I have to add something here so it will post

[David M]

Pelagic....you pretty much nailed it. So I am calling you the winner.

Just a couple very minor points. It's an Acoustic Doppler Current Profiler. This device measures the velocity and direction of the current at different depths from the surface down to the bottom. Another cool feature is that most ADCP's are bottom tracking which means that it gives the direction and velocity of the current with respect to the bottom...not just with respect to the boat, which would be pretty much worthless information for a scientist. So you get the bonus question.

Differences is densities cause currents to run sometimes diagonally or for currents to run in two opposite directions. This is caused mostly by density differences caused by salinity and sometimes by differences in temperature and sometimes combination's of both.

In a bay or estuary such as the San Francisco Bay, the high tide and slack only occur at the same time at the ocean itself...near the Golden Gate Bridge. As you get further inland, you can be on a falling tide with a flooding current. This is some sort of physical phenomena which I have never been able to visualize in my head....but the difference can be over 4 hours when you get far inland. This is not caused by river current either. Because in the south bay, where there is effectively no river current in the dry season, you get the same effect.

Your up to bat Pelagic! Nice job

[Pelagic]

Thanks David. I agree with others that anyone can toss a Challenge in after the previous one has been answered…so as to keep this flowing and to get diversity.

Also CaptainJeff I am afraid if this game caught on we might have too many “What would you do” Headers on the front page .....that might annoy some (just my opinion).

Would be great to hear some mechanical or engineering challenges ….as that is my weak point

(or any obscure lesson that someone remembers)