capnsensible
Well-known member
Don't know. But it was a great photo opportunity whilst sailing round Europa Point for a long time. ....
Anchored cruise ships are having anchor problems
- Thread starter Concerto
- Start date
Fimacca
Active member
This one was fine and was hanging on as I passed her (Jewel of the seas) off poole yesterday. She had a spare.
Funny, when you snap them close they don't look 90,000 gross tons and 300m long........
Funny, when you snap them close they don't look 90,000 gross tons and 300m long........
MathiasW
Active member
I am not often in this forum, so am kind of late now... Still... Catenary, my favourite subject... 
For some 18 months now we have been on the barefoot route, with some Corona-related lock downs and change of plans, but ok. During this time at anchor I realised that the teaching by the German sailing association DSV with regards to anchoring is utterly wrong, if not dangerous. Anchor chain length = 3 times water depth is the only correct answer possible when sitting the exam at DSV. Really? When the minimally required anchor chain length is dependent on so many parameters... Wind strength, vessel type and windage area, swell, type of chain and snubber, etc., etc. And yes, even the water depth!
The RYA does not seem to be so much different in their advice, although I have seen there also the British Admiralty rule, which is a much better albeit often very conservative advice.
I have used the lock down time in Panama to dig into the physics of anchor chains. When is a chain working well? (in deep water) When is it not? (in shallow water) And why is that so? (a chain that is almost horizontally stretched has very little further headroom to store any additional potential energy). When is a snubber / bridle needed most? And needed because it needs to store the energy the chain cannot store, and not to suppress some clanking noise from the bow. (shallow water again)
If you are interested in this topic and have some time to spare, here is my long essay on this topic: Catenary Anchor Chain Length - Die Kettenkurve - Fun Facts - SAN
I have also described the eco-friendly way of anchoring in the Tuamotus, where "floating chains" are used to keep the chain away from corals. You may think this cannot work, and so did I, but it does! You will also find some links to free online tools that allow you to calculate the minimally required anchor chain length.
Feedback always most welcome! Mathias, SV SAN
For some 18 months now we have been on the barefoot route, with some Corona-related lock downs and change of plans, but ok. During this time at anchor I realised that the teaching by the German sailing association DSV with regards to anchoring is utterly wrong, if not dangerous. Anchor chain length = 3 times water depth is the only correct answer possible when sitting the exam at DSV. Really? When the minimally required anchor chain length is dependent on so many parameters... Wind strength, vessel type and windage area, swell, type of chain and snubber, etc., etc. And yes, even the water depth!
The RYA does not seem to be so much different in their advice, although I have seen there also the British Admiralty rule, which is a much better albeit often very conservative advice.
I have used the lock down time in Panama to dig into the physics of anchor chains. When is a chain working well? (in deep water) When is it not? (in shallow water) And why is that so? (a chain that is almost horizontally stretched has very little further headroom to store any additional potential energy). When is a snubber / bridle needed most? And needed because it needs to store the energy the chain cannot store, and not to suppress some clanking noise from the bow. (shallow water again)
If you are interested in this topic and have some time to spare, here is my long essay on this topic: Catenary Anchor Chain Length - Die Kettenkurve - Fun Facts - SAN
I have also described the eco-friendly way of anchoring in the Tuamotus, where "floating chains" are used to keep the chain away from corals. You may think this cannot work, and so did I, but it does! You will also find some links to free online tools that allow you to calculate the minimally required anchor chain length.
Feedback always most welcome! Mathias, SV SAN
Neeves
Well-known member
The spare will be on the foredeck. I'm not sure what they call the twin in the other hawse pipe.
Jonathan
Neeves
Well-known member
I am not often in this forum, so am kind of late now... Still... Catenary, my favourite subject...
Feedback always most welcome! Mathias, SV SAN
Mathias,
You should visit more often
Jonathan