Single Handing

My insurers Curtis Marine with the AXA "Stay afloat" policy (£180/annum, £14,000 sum insured) restrict my single-handing to local waters and daylight hours.

Who do you insure with and what restictions do they impose on you for single handing?
 
I have not had the time to read through all of the threads but would like to add a few things which I hope will help.
1. Do it! I may be a bit of a miserable git but I love to sail alone.
2. My plan for coming alongside, I have a rope with a clip on one end and a loop on the other. Decide which end is suitable for available cleats. Fit fenders down whichever side is correct for the conditions. feed the rope through a centre fitting and wrap around a winch. Come slowly alongside and step ashore with both ends of the rope, secure the end to the cleat and pull the winch end to secure the boat. Then you have time to sort bow and stern ropes.
3. When sailing away from other boats, rig a trailing rope. With my old boat I copied a Frenchman I once met. The rope came onboard through a cockpit drain, went up over the autohelm and down to a strong point. any pull on the rope would drop the autohelm off and should allow the boat to head up into wind and give you a chance to get back to the boarding ladder.
I hope this helps, good luck.
Allan
 
[ QUOTE ]
weird!! However, I only have the tiller pilot - it is connected to the seatalk bus (did that one winter) but only so it can steer to wind ... I can't work out why the pilot would need speed in it's calculations - it is doing 1 of 3 things (depending what you have connected)
1) steering to a compass course - this is the most used/standard way (so I believe)
2) steering to wind - connection to wind instrument keeps the wind in the same place over the deck
3) steering to a waypoint - taking course from a GPS/plotter to steer you to a waypoint ......

Can't see why the unit would need log in any of those ... weird ... but probably a question for another thread.

[/ QUOTE ]

Speed can be quite useful for the autopilot, the faster you go the more turning effort you get for any given rudder angle, go fast smaller rudder movements and vice versa.

As for single handing, plan ahead, plan ahead, plan ahead. Also keep a good look out, there is no one else to do it for you. You should always be working out how long before any of the vessels in sight can hit you if they take an instant dislike to you and this will give you the time you have to go below or do some other concentration demanding activity.
 
I would have thought that it needs the speed for calculating how much offset to apply to correct for current? I suppose the pilot (human or electronic) can just keep progressively pointing up current until the course is held - but knowing your speed and rate of increase in off-track would enable a calculated heading. I guess. /forums/images/graemlins/smile.gif
 
GJW - the original policy restricted single-handed to daylight hours but on request they extended it to cover overnight, albeit with an increased excess.
 
[ QUOTE ]
Speed can be quite useful for the autopilot, the faster you go the more turning effort you get for any given rudder angle, go fast smaller rudder movements and vice versa.

[/ QUOTE ]
Ok - I could see that, but if your pilot is steering to wind/compass or waypoint then it shouldn't have any massive deviations to worry about - a small alteration and see what effect that has on the heading - if not quick enough then apply a little more - will take milliseconds to do ...
Even on Autotack - it will just progressively push the helm over - and could measure the rate of heading change ....
 
I insure with Bishop Skinner with an AXA Stay Afloat policy. My excess for single handed is increased to £350 for UK Inland and UK Coastal waters excl. IoM NI and CI, but the CI restriction is being lifted this year to cover me for crossing the channel in June. My annual premium is £200 for £14,000 cover.
Also one condition of single handed is there has to be a tiller pilot available.
 
Instrumentation and controls engineers make a living out of designing and setting up such control systems with proportional and differential control, feedback, deadbands and hysteresis. And that's for systems that are less "touchy-feely" than steering a boat, each with its own mass, speed, centre of effort, steering characteristics...need I go on?.
Dammit - you've encapsulated their entire professions in a sentence - if only they all knew it was so simple! /forums/images/graemlins/wink.gif
 
[ QUOTE ]
[ QUOTE ]
Speed can be quite useful for the autopilot, the faster you go the more turning effort you get for any given rudder angle, go fast smaller rudder movements and vice versa.

[/ QUOTE ]
Ok - I could see that, but if your pilot is steering to wind/compass or waypoint then it shouldn't have any massive deviations to worry about - a small alteration and see what effect that has on the heading - if not quick enough then apply a little more - will take milliseconds to do ...
Even on Autotack - it will just progressively push the helm over - and could measure the rate of heading change ....

[/ QUOTE ]

Indeed, and I think all autopilots do this, but that does mean doing observing and doing more, do you when altering course just keep adding small increments of rudder to get to the turn rate you require or do you say to yourself I am going slowly so I will need a lot of helm etc. When an instrument can use available information to do it's task better why deny it that information. Yes it doesn't need it but it can work better with it.
 
I do a lot of coding with many conditional statements .... so I understand how a lot of these electronic gizmos could work - but sometimes I don't understand why they appear to rely on information that I wouldn't contemplate using!
 
Log feed to the Autopilot

I'd have to analyse my helming to answer that one properly .... in 30 years I've sailed everything from my 30' 3.5tonne boat to a sub 100Kg racing dinghy - each require a different helming technique .... but I'd quite happily say that I do (without concious thought) analyse the rate of turn against how much rudder I've applied.

It is probably most noticable in light winds where the boat has stalled and drifts sideways - then you have to really think about the rudder and straighten it to gather speed even though you are not pointing in the right direction ...
 
I'm not a controls engineer - I left that stuff at Nautical College but here's how I could see it going:
Boat speed through water is not included:
Example - when boat yaws +/- 5 Deg apply -/+ 3 deg rudder for 3 seconds or until boat yaw = -/+ 5 deg.
This probably would result in long slow curves from +/- 5 deg along the chosen heading if the boat was going slowly or continuous yawing by +/- 5 deg if going fast.
Add a control statement to the effect that if boat speed is fast apply 1 deg of rudder for .... or if boat is slow add 6 deg of rudder to compensate for less response and you have a better chance of the hunting damping down.
Now add more statements:
for the first few degrees off dead ahead get the rudder to move slowly and if the yaw increases or does not decrease fast enough get the rudder to move faster/further to head off that broach.
For a higher rate of yaw apply more rudder and/or faster.
Etc.
That only accounts in part for making the boat stop yawing - it doesn't even really address going in a straight line!
But you either already know this or could work it out for yourself - plus I just realised I'm into SERIOUS thread drift but having typed this I feel reluctant to scrub it again.
 
Thanks for that - I hadn't really thought about it too deeply - I know that electronic kit is usually a lot more sensitive than human control - so would notice a 5 degree yaw long before it became 5 degrees - and would be applying opposite lock appropriately - whilst our pilot is on (no feed from log) it is quite often giving minute tweaks to the helm - pretty much the same way I would if steering.... I suppose it could include speed in the calculation, but I couldn't quite see what additional benefit it would achieve!
 
I clip on perminantly when single handed, even in the cockpit, but then i can't swim. I have seen a system where the bloke had his jackstays rigged to disconnect the autopilot if they had a sharp pull, which could be worth figuring out. A thermos and a bucket in the cockpit take care of most of your needs. When coming alongside, i hook the sternline over a cleat then put the engine ahead, thid will hold the bow in whilst you make fast. if your using a swinging mooring, put a big snaphook onto a long line and lead it from the bows, outside the guardwires to the cockpit, snap onto the buoy ring as soon as you can reach it, then use it to hold her whilst you make fast propperly.

The trick is to just get out there on a calm-ish day and see what works for you.
 
The real difference between your autopilit, and you is that you absorb and use information in the background, if you monitor your helming you will find you adjust the ammount of rudder you use according to the circumstances. Interestingly this is actually a problem I am having at the moment having changed from tiller to wheel steering as I hve not yet got a real instictive feal for the connection between wheel movement and rudder movement so especially in slow manoeuvering I reall have to think about how much to turn the wheel to get the effect I really want.

Early autopilots which had manual controls for rudder gain sensitivty and deab band had no need for speed input because that was factored in by the operator applied settings. Now all autopilots have some level of adaptive control algorithm and little operator adjustment having a speed input will help the poor little thing work things out for itself. Of course it will work without speed input just as the early ones worked whatever setting the operator applied, but it will work more to the manufacturers plans and probably the users satisfaction if all usable information is supplied
 
A floating line astern when single handed can be a useful last resort, assuming you can get back on board. If not then at least you will be with the boat when it either collides with another or runs ashore!"!!
 
You must log in or register to reply here.

Other threads that may be of interest

Sea Change
Mini sandblaster for rust spots on keel?
2 3 4
Replies
63
Views
2K
Mister E
M

Share this page

Top