Hurricane avoidance

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W

william

You are underway on course 050T and your maximum speed is 13knot. The eye of a hurricane bears 100T, 120 miles from your position. The hurricane is moving towards 275T at 25knots. I you maneuver at 13 knots to avoid the hurricane, what could be the maximum CPA?
 

Ctskip

.
Sep 21, 2005
732
other 12 wet water
I'll give it a guess.....12

Can you give us more to go on? Keep it up, Ctskip
 
W

william

72 Miles

The closest point of approach is 72 miles. I haven't figured out exactly how, but I am looking up the answer as I write.
 
N

Not tellin

Stupid question: what does the 'T' mean

Is "T" stand for true north ? Stupid question, but not knowing is stupiter.
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
about 40 miles

from the eye if the both courses are held. It would occur about three hours after the positions given. r.w.landau
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
William is right if you change course to 355 T and

that would occur about 5 hours from the positions given. r.w.landau
 
Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
Not on my boat

No way in hell on a monohull sailboat under 100' will you be going 13 knots in those conditions because you will be sailing into the wind and you can't exceed hull speed into the wind.
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
Not tellin, T is for true bearing off the chart

M would be magnetic bearing off the compass. r.w.landau
 
C

Clay -oops

That's what I thought

Frankin speakin I would be on the run hi tailin, it wouldn't get within 50 miles of me or I'm bear-polin and goin under.
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
Franklin, this was probably a power boat question.

I assume that because if not the boat would be 94' long at hull speed. r.w.landau
 
Jul 20, 2005
2,422
Whitby 55 Kemah, Tx
Clay

You're dead on...in that situation, you are actually 5 dgerees on the clean side of the storm so you want to set a course to run with the wind and not change course when the wind changes to your aft starboard, but when the wind starts to get dangerously close to your beam, the adjust your course to keep it the wind and waves aft, but when the wind shifts again, it's time to heave-to or lay ahull or throw a sea anchor because you don't want to be sucked into the storm (remember, hurricanes suck the air into the eye counter clockwise). Try to go as fast as you can at first to get out of the path of the storm so if you have a storm sail, put that one up. The cool thing about the furling mains is that it is very easy to put up a storm sail because we have a second track. Just the other day I was talking to a buddy who has a storm sail and he said he never used it...not that he hasn't been in the conditions, but because it's not something you want to do once the winds have hit 35 knots on his rig. He has to disconnect the main and remove it from the track and then try to raise the storm sail with the main in the way.
 
C

Clay

Sea anchors' good if I'm riding to high

My rollers hold a good storm jib, but I need a good dunking before I have enough sense to shorten, I ride with both port & starboard sheets in hand, yeehaw...I'd be tempted to run it out, probably get 9 knots out of her.
 
Oct 11, 2007
105
Island Packet IP31 Patuxent River, MD
Accepting R. W. Landow's assumption that this is a 13 knot powerboat question, and assuming no geographic problems. I would follow standard Navy procedures and go at max. speed at right angles to the Hurricane's course. In this case this means heading 190 degrees at 13 kts to put you on the hurricane's less windy semicircle. This way of avoidance has been validated by 28 years driving ships in the Navy (and many instances of hurricane/typhoon avoidance, including some unsuccessful ones) . You never want to get into the dangerous semicircle because you may get dragged into the most violent quadrant of the storm (front right quadrant).
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
wjssr, I agree with getting into the left quadrant

I don't know what I was thinking or maybe I just wasn't thinking. r.w.landau
 
S

Shane

wjssr?

Does'nt that put you right thru the middle of the storm? From my rough sketch you would cross the storm's path right about the same time. I would change heading to 000 to get out of the way. Of course I have never had any training in storm avoidance. Please educate me on you reasoning. I am interested. Shane.
 

Ross

.
Jun 15, 2004
14,693
Islander/Wayfairer 30 sail number 25 Perryville,Md.
Shane. The storm is east of your position

and headed west if you turn and head south in about five hours the storm should pass about sixty mile behind you. That would put you on the trailing edge of the storm where the winds are least.
 
P

Peter

too close

The problem with the scenario is that you are in all likelihood within the 34 knot wind radius and still most likely within the 50 knot radius. At this point the only thing you can do is run before the wind to let the storm bring you around and then hold your southerly course as you come around through the southwest quadrant, all the while saying your prayers. At this point, calculating the closest approach would be futile,since you would neither be heading on that course from a far earlier time or by now the wind and seas will have made that course impossible.
 
P

Peter

qualify my remark

I would like to qualify my statement, since Bowditch recommends keeping the wind on the starboard bow when positioned as such relative to the storm (which a course of 050 does). It is the fury of the storm at this point, and the proximity to the "navigable" semicircle that would guide my decision. I don't have any maneuvering boards on hand, but if I did, in a few minutes I'd have an answer to the CPA and a perhaps better idea of what to do.
 
Jun 2, 2004
1,438
Oday 25 pittsburgh
Ross is right and so are you Peter, kind of.

The winds are circular in a counter clockwise motion. If you do as Ross said, the wind would probably hit you directly from north with the wind veering to the west as the storm passes. The wind would be over the stern so you would be running if you were in a sail boat. Ross your calcs are about right at 60 miles and your course should be about 185T. The storm would pass about due North 5 hours after the original positions. If you would have headed anywhere north, you have been slammed with the leading edge of the front. Say at 60 miles from the eye, the winds are 50 Knots/hour. If you were heading north at 13 knots and hit that wind you would be experiencng 63knots of wind off your starboard bow. If you headed south you would experience 37 knots of wind over the stern. r.w.landau
 
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