Main Racing Autopilot ('Nick')
- The brain unit was reset by the US NKE distributor and will be overnighted back to SF
- Spare parts were purchased so we can continue debugging this weekend without having to depend on another shipping cycle since the start is Wednesday
This is by far the favorite means of self-steering.
- It has a very low power consumptions (as far as autopilots are concerned) and during the day would take in as much power as the solar panel would be able to push into the battery, thus not depleting them (our experience so far with the big battery) -
- It has a gyrostatic graphic computer which means that is knows about wave and how to steer around them making it pretty effective
- It is good both downwind and upwind (windvane systems are not very good downwind as they rely on apparent wind, and particularly not in a surf as something the apparent wind can be zero! and can cause round-downs)
- It has a fast response rate (adjustment) so any small change can be corrected very quickly making it a pretty competitive robot-driver
- It is named after a friend of ours who is one of the best sailors I know...so it has to live up to some pretty high expectations
- The whole installation is below deck which makes it less likely to get salt, wind, UV damage, etc...
- It can apply a lot of force on the tiller (pretty big ram!!!!) so can steer is pretty high winds (usually autopilots break down in heavy breeze, which is when windvanes actually become more effective as apparent wind increases)
- It can be operated with a remote control (imagine you are at the bow and need to make a small adjustment, well, you can!)
I think that we will have tried everything we can on that one, and there is still hope that we can fix it by Wednesday
Spare Tiller Pilot ('Ray')
- The corroded connector was changed
- It just needs to be tested (eg, the second instrument panel needs to be screwed back on so we can bring power to the autopilot)
It is not a favored method of self-steering because
- In any kind of heavy breeze, it will break
- it is slow, and does not know about waves, so it basically is a very crappy driver
- It is all self-contained and mounted above deck and subject to a higher risk of breaking on the job even in light air
- It cannot withstand as much force as the other autopilot
- For a worse performance, it eats up a lot more power than the NKE system
There is no reason to believe that this one will not work by Wednesday. In any case, it was always meant to be a backup though...
Sheet-based self-steering ('Elise')
Something like the below is what I will be trying out this weekend on a trip to the Farallones. It works according to the same principles as heaving-to, eg. uses tiller and sails to counteract each other and keep the boat in line. The minute the boat wants to round up because of a puff, the tiller is pushed to windward and prevents this from even starting. In a lull, the exact opposite happens. The tiller is connected to the main sheet that way, thus react symbiotically with the mainsail.
Technically, it can work for all points of sail except dead downwind but anything less than close haul isn't very stable and it isn't clear that this would work.
- Big pro is that it requires no power, so if I need an autopilot at night for any reason (and for more than a few minutes at a time which the batteries will be able to accommodate without any problem, such as the need for a gybe, or a bio-break), this could be a solution
- If you can achieve balance, it can be very stable. Unfortunately, if the wind velocity keeps changing on a course that's not close-hauled, you probably have to constantly fiddle with the sails or the system to get to that balance. The fact that Elise behaved under simple bungee (not connected to the sheeting system) during Spin Cup is very encouraging though and makes me feel pretty good about this whole thing
- It should be pretty robust, and even though things can break, replacement parts are easy to come by and will be on the boat anyway (turning blocks, lines, surgical tubing or bungees)
- It is super light
- It is super cheap :)
- It probably isn't very competitive but it might be better than 'Ray' (Ray is our Raymaine autopilot) - and it would have to be called 'Elise' as it really is the boat steering!!!
Bungee-based/blocked tiller self-steering ('Bungee')
- This is what Nathan used during spinnaker cup
- Bungee is connected to the tiller and probably toe rail on either side and can absorb shocks yet allow the tiller to mvoe with waves and right itself
- Only good for a few minutes at a time (but that's what I woudl expect 'Ray' to be good at anyway...) and might allow for longer periods only in particularly stable conditions (like 'Ray')
- Good backup for sheet-based steering
Heaving-to (the 'P' of sailing)
- Heaving-to is great (and the reason why autopilot are NOT a safety requirement, the boat can be kept safe without any means of self-steering) but is absolutely not competitive!!!!! Whatever distance you have covered steering is lost while you are parking...it is like racing in the Paris-Dakar and decide to park your car while the others are driving forward...Or imagine someone doing the Tour de France and take a nap in the afternoon while everyone else keeps going...
- So this is the safety backup of everything...it's just very slow since you're basically drifting...and often away from where you're supposed to be going!
- You can heave-to for a few minutes close to land if you need to have something done (like go to the bathroom, make yourself a cup of tea, etc...) so long as you have sea-room
- You can heave-to for much longer at sea (so long as you have sea-room) if you need to sleep/rest
- If you get close to shore, and you need to sleep/rest, I'd pull in somewhere and anchor or moor somewhere (from a safety perspective), I wouldn't rely much on an autopilot either there and take long naps. Rocks, traffic, etc... loads of stuff can be happening
The drawback with all these systems is that they are bling :) So the AIS system is pretty important. If you don't have crew on the boat to freak out about ships (someone knows who I am talking about), you need an automatic system to do that. I will call the ship alarm system on Elise 'Heather'
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