Cruisers Forum
 

Go Back   Cruisers & Sailing Forums > Seamanship, Navigation & Boat Handling > Seamanship & Boat Handling
Cruiser Wiki Click Here to Login
Register Vendors FAQ Community Calendar Today's Posts Log in

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 01-08-2017, 11:21   #181
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Posts: 4,033
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by a64pilot View Post
Re pilot thing, just like I'm sure there is a huge difference between a recreational sailor and a professional mariner, same for private pilots and precessional ones.
Definitely. In fact I had a private license, but would never call myself a pilot. It ever came up I just said "yes, I flew small planes", sort of like "going to the horn" vs " rounding the horn". Have to give respect the actual professional accomplishments.

But, for this topic, he seems to be an actual professional pilot - large (737) biz jets apparently.

Quote:
Originally Posted by Drew13440 View Post
p.s. for you guys floating around the South Pacific, coral reefs grow about a foot every decade (I think). If your chart is from an 1842 British Admiralty survey, you might consider the arithmetic before assuming you're safe...
The French have pretty recently surveyed the Society Islands - these chart datums are no longer from Captain Cook era.

We did sail in the pacific our first time before the resurvey, and there were significant position fixing errors - e.g. Whole island out of place by miles, and often incorrectly rotated also (so one end of an island would have more north error than the other). But I can't say I ever saw a reef that had grown so much it was definitely noticable among the position errors, even reefs from captain cook datum era.
estarzinger is offline   Reply With Quote
Old 01-08-2017, 14:29   #182
Moderator
 
JPA Cate's Avatar

Join Date: Nov 2011
Location: aboard, in Tasmania, Australia
Boat: Sayer 46' Solent rig sloop
Posts: 29,288
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Follow the 200 ft. contour 100 ft. off the reef, eh. OMG.!

For the people who haven't been out there, the fringe reefs come up very steeply from the bottom. It is about 100 ft. from that contour to 0 depth. With a large sea running, the odd wave that's 40 % higher than the averages, which occur with frequency, those are not rare, could sweep you right over onto the reef. Just as a rule of thumb, it doesn't take long to get the sea room back, when you line up for an entrance (you'll note on the copy of the real chart that there are compass headings for the safe passes), and in our sextant days, we would have left a 5 mi. off the reef safety margin, and if the seas were big that night, and it was my watch, I still would. There's no need to go so close, and a ton of danger.

Capt.'s Wife, this is one mistake you can easily avoid by the simple practice of generous stand off distances.

The possibility of night vision loss can be dealt with by dim zone lighting, and by the practice of keeping your better eye closed if you have to go do something involving light. Dishes can be kept in the sink and done in the daytime, by available light.

Sight, smell, and sound are all clues when you are approaching land. You'll notice the smell a long way off, of sweet vegetation. The surf, with 2 m. (roughly 6+ ft.) will roar on the reef. The foam of the break looks white. The break on the reef shows up well on plain old fashioned radar, and gives you another datum for keeping your standoff distance. There is nothing in this to make you fearful. There are skills to acquire.

12,000 nautical miles gave those poor guys a false sense of security, pride goeth before a fall. There is no reason to assume that your experienced skipper would make those particular errors. Evans, with more short-handed sea miles than many, didn't comment very much on their having dinner at the CPA to the reef, but way better to have waited supper till it was safely passed, don't you think?

We all have made dumb mistakes at some time or other, I made one yesterday, there's no immunity. Safe sailing is vigilant sailing, and respecting your environment.

This grounding is not the fault of the Navionics, which seemed to have worked perfectly.

Ann
__________________
Who scorns the calm has forgotten the storm.
JPA Cate is online now   Reply With Quote
Old 01-08-2017, 14:32   #183
Registered User
 
44'cruisingcat's Avatar

Join Date: Sep 2006
Posts: 9,398
Images: 69
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Port Resolution on Tanna is much shallower than in Cook's day, although that's due more to volcanic activity than coral growth.
__________________
"You CANNOT be serious!"


John McEnroe
44'cruisingcat is offline   Reply With Quote
Old 01-08-2017, 15:14   #184
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Posts: 4,033
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

There is an interesting tension on a cruising boat (and perhaps more broadly in life). If you are not paranoid and careful enough you will lose your boat, BUT if you are too paranoid and careful you will never do anything interesting and challenging.

Most cruising couples cycle thru this spectrum. They start out on the careful end, then they build miles and everything is going well and they get more "adventurous" / less careful, then they make a mistake or have some bad luck and get slapped down hard, and they cycle back to careful.

Even after two rtw's we still cycled thru that continuum. One of the more difficult times Beth and I had was the first time we were in chile. Before that she had been the careful prudent one and I the adventurous risk taker and we had sort of reached a good balanced decision making process. But when we got to chile it was initially a bit beyond my comfort level (and I had just made a bad mistake in Iceland which wrecked my confidence) and I wanted to be extra careful, while she had sailed thousands of miles to this special place and wanted to go everywhere and see everything and somehow felt very comfortable. The reversed roles sort of threw us for a loop for a while.
estarzinger is offline   Reply With Quote
Old 01-08-2017, 15:29   #185
Registered User

Join Date: Jan 2015
Location: Victoria BC
Boat: Rafiki 37
Posts: 1,390
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

I gotta say from reading that blog they've really dealt well with it - probably far better than I would have.
__________________
www.saildivefish.ca
alctel is offline   Reply With Quote
Old 01-08-2017, 16:19   #186
Registered User
 
Dave_S's Avatar

Join Date: Jun 2016
Location: Brisbane Australia
Boat: Schionning Waterline 1480
Posts: 1,987
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

If you (anyone) were rounding that reef at night and didn't know the area how much room would you give it.


Lets say there is a 15kn southerly and you are passing to the south.
__________________
Regards
Dave
Dave_S is offline   Reply With Quote
Old 01-08-2017, 16:26   #187
Moderator
 
Jim Cate's Avatar

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,387
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
If you (anyone) were rounding that reef at night and didn't know the area how much room would you give it.


Lets say there is a 15kn southerly and you are passing to the south.
At least two miles. Likely more... and that with the previous knowledge that the charts are in agreement with reality, either from observation or comparison with satellite imaging.

Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
Jim Cate is offline   Reply With Quote
Old 01-08-2017, 16:31   #188
Registered User
 
Dave_S's Avatar

Join Date: Jun 2016
Location: Brisbane Australia
Boat: Schionning Waterline 1480
Posts: 1,987
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Why so far. I expected 400m (1/4 mile).
__________________
Regards
Dave
Dave_S is offline   Reply With Quote
Old 01-08-2017, 16:37   #189
Moderator Emeritus
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Jacksonville/ out cruising
Boat: Island Packet 38
Posts: 31,351
Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
If you (anyone) were rounding that reef at night and didn't know the area how much room would you give it.


Lets say there is a 15kn southerly and you are passing to the south.


They obviously didn't know how close to it they were, so if you don't know how close, how do you know how much room you have?

I've not read the blog nor even this whole thread, but as a guess from investigating aviation accidents, I'd likely blame complacency, AKA sometimes known as overconfidence.
I have crashed one airplane, and it was due to overconfidence / complacency, airplane flying by comparison to what I was used to is easy, you can do it half asleep.
It bit me when I looked out and all I could see was dirt less than 200' away.
I almost made it, really maybe just 20 more feet and I would have.

I assume with a chart plotter navigation is just so easy that no real good look was done, just drop a waypoint and go. Where they hit was well away from the island, Maybe they didn't even think exposed reef?
One oops is all it took, and I bet that only he did the navigating, that no one ever checked it.
FAA allows me to inspect my own work, nobody has to check behind me. I don't like that, Military had a hard fast rule, you were never allowed to inspect your own work, I think that is smart.
If he had another trained to do Nav, and they always had one check the other, want to bet there would not have been an accident?
Teach your crew to Nav if you have them and have them check your plan and don't get defensive if they point out a mistake, that is why they are checking
Back to that FAA, study years ago was trying to determine how an expert airplane driver that was well rested, had no home issues or other stressors just one day did something that a first year flight student wouldn't.
They never did figure out why, best they could do was put an acronym on it, called it SLOJ for sudden loss of judgement, which means no matter how good we are, we all mess up, best way to mitigate it is to have another always check your work, likelyhood of both having SLOJ simultaneous is ridiculously high.
a64pilot is offline   Reply With Quote
Old 01-08-2017, 16:49   #190
Moderator
 
Jim Cate's Avatar

Join Date: May 2008
Location: cruising SW Pacific
Boat: Jon Sayer 1-off 46 ft fract rig sloop strip plank in W Red Cedar
Posts: 21,387
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
Why so far. I expected 400m (1/4 mile).
Dave, consider that there is an onshore wind, usually an onshore set, it is dark.... There are any number of reasons that you or your boat might suddenly be compromised in ability to maintain that 1/4 mile offing. A sail blowing out, a sheet parting, engine failure, steering failure, collision with debris, lots of possibilities. And then, you could fall asleep, trip and fall, injuring yourself, have a severe gastric event and need to be below for a while, just loose concentration and contact with reality (happens to me all too often!).

If only 1/4 mile off, one could be on the reef in a very short time. But the real issue is that there is nothing to be gained from being close when passing by Huahini. So, why add even a small amount of risk?

Jim
__________________
Jim and Ann s/v Insatiable II, lying Port Cygnet Tasmania once again.
Jim Cate is offline   Reply With Quote
Old 01-08-2017, 16:54   #191
Registered User
 
Group9's Avatar

Join Date: Sep 2010
Posts: 2,909
Images: 10
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
If you (anyone) were rounding that reef at night and didn't know the area how much room would you give it.


Lets say there is a 15kn southerly and you are passing to the south.
At night, I give anything that can sink my boat a wide berth. I'd say a couple of miles, too. What's the hurry? Stand off and wait for daylight when you know you're going to be passing by a reef. Especially in the South Pacific where you know there are variations in where things are and where the charts say they are. I'm still amazed at how many people will run an unfamiliar reef passage in the dark because they have a GPS chart plotter..
__________________
Founding member of the controversial Calypso rock band, Guns & Anchors!
Group9 is offline   Reply With Quote
Old 01-08-2017, 16:56   #192
Registered User
 
Dave_S's Avatar

Join Date: Jun 2016
Location: Brisbane Australia
Boat: Schionning Waterline 1480
Posts: 1,987
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

I mean no disrespect for the people on the boat, I am learning from these unfortunate threads, hoping to avoid learning too much by my mistakes.

I'm trying to figure what I would should do. I was shown 400m if you don't know the area and 200 if you do. Some posts in this thread are talking about 10nm. I feel if the charts are out that much your going to run into a pile of boats not reefs.

I look at my charts and I would have recognised that as reef or at least 0 depth at low tide and would consider it as the edge of the island and set a course 400m to the south of the edge of the reef. In this case that would have worked fine, but if its not enough all the time I should change my view.

Jim said 2nm at least and I value his experience more than mine.
__________________
Regards
Dave
Dave_S is offline   Reply With Quote
Old 01-08-2017, 17:12   #193
Senior Cruiser

Cruisers Forum Supporter

Join Date: Aug 2009
Posts: 4,033
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

^^ at night, no particular reason to hurry/cut it, first time, 2nm is about right imho. It is only an extra 15 minutes (on that boat in those winds).

You really want to stay out in deep water so you do not get odd breaking waves as swell rolls in over the shallowing up to the reef.

Gps is pretty accurate most of the times, but we have seen odd 100m and (very very occasionally) even 300m glitches (which persist for a few minutes). Not sure what causes them.

And sometimes local boats which know the area well cut corners and I prefer to be out away from that possible"local track", with room to maneuver.

Now in daylight it would be a bit different story, but you should still try to stay in deep water, because rogues can hit you unexpectedly in daylight (btw see the low speed chase incident report for a good discussion of exactly "how close", in a racing context where closer=saved distance, so cruisers should be more conservative).

They had already missed daylight to enter the pass, so there was no hurry. I don't know what their plan was - to heave to off until morning, or to try the pass in the dark, but in either case 15 minutes more on the rounding would not have mattered.
estarzinger is offline   Reply With Quote
Old 01-08-2017, 17:58   #194
Registered User

Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
Why so far. I expected 400m (1/4 mile).
1/4 from where? It kind of begs the question since you are measuring from the charts position, which is exactly what you don't trust.
A Kiwi boat was lost a few months ago on passage from NZ to Tonga after they redirected for Fiji. The outlying atol they grounded on is charted off by probably a mile or so. In this case I don't think they realized it existed at all.

If you aren't making landfall AND you know there is nothing further away to then get too close to, then a couple miles is probably a good distance.

Prior to GPS navigators often had to make landfall and head in 'too close' to try and get a positive fix on something (like a steeple or tank or odd tree, lighthouse, ....) to update a DR position that had been running for many hours or days without a proper fix.
__________________
Paul
Paul L is offline   Reply With Quote
Old 01-08-2017, 18:14   #195
Registered User

Join Date: Jul 2016
Posts: 797
Re: Leopard 46 lost in French Polynesia - stunning rescue pictures

Quote:
Originally Posted by Dave_S View Post
If you (anyone) were rounding that reef at night and didn't know the area how much room would you give it.


Lets say there is a 15kn southerly and you are passing to the south.

I thought this was interesting and looked up the charts. There's a significant depth change from 2000 meters to fewer than 200 in about 4 nm. I would be inclined to follow the surveyed 2000 meter depth around the island until I'm able to get to the right bearing for the recommended track that larger ships use, before I would begin really approaching closer.

It is a night approach at a new island - one nm off the pass the depth is still 500m. I'd really have to be sure and committed that I can hold the course before I'll commit. If I can't do it half a nm out I'm declaring no go and going around.
__________________
We are sailors, constantly moving forward while looking back. We travel alone, together and as one - to satisfy our curiosity, and ward off our fear of what should happen if we don't.
SV DestinyAscen is offline   Reply With Quote
Reply

Tags
enc, French Polynesia, leopard, leopard 46, lost, rescue


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Fort Lauderdale Stunning Ketch boatgirl123 General Sailing Forum 29 18-06-2013 13:31
Stunning Blog hoppy Flotsam & Sailing Miscellany 64 06-11-2011 12:55
Stunning Circumnavigation SaltyMonkey General Sailing Forum 6 30-07-2010 06:05
Stunning Bay Area Refurbished Vessel TaoJones Monohull Sailboats 15 23-09-2009 09:40

Advertise Here
  Vendor Spotlight
No Threads to Display.


All times are GMT -7. The time now is 21:55.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.