Steering Off the Wind with TP32 Tiller Pilot

[witzgall]

We currently have a Simard TP32 Tillerpilot, and no wind instrument. The unit documentation states that if you have both wind and water speed input, you can use the TP to steer relative to the wind.

Has anyone ever used this, and if so how did it work In comparison to a wind vane?

Here is the bigger question, and background. I have a Sailomat 3040 windvane that needs refurbishment. This is a unit that uses an auxiliary rudder. The entire mechanism is heavy, about 60lbs. More with mounts that need to be made. After mounting the arch and solar panels, we are concerned about adding more weight to the rear of the boat. The Fulmar has some good buoyancy in the rear, but all of the water (36gal) and fuel (24gal) is behind the engine. There is also a currently unused system of THREE extra fuel tanks back there, 11,11 and 12 gallons with a transfer/polishing system, that the original owner installed for a Caribbean cruise. We will be adding some more water storage, either in the bow, or under the settees.

So, what to do, what to do. Add wind vane, and try to use the tiller pilot to wind steer? Install the Sailomat and remove one of the tanks (needed to remove at least to install) saving a bit of weight, or remove all three tanks, transfer system and hoses, saving perhaps 40lbs?

Other facts:

Our engine uses ~1/3 of a gallon an hour. at this rate, 24 gallons = 73 hours of motoring.

We are looking at cruising the east coast, Bahamas, and Caribbean. I think the Sailomat would be only really useful in the Carribean and beyond, if we ever get to beyond.

Since we have an unprotected spade rudder, the Sailomat would add an emergency rudder.
Chris

[Paul L]

Downwind sailing to the apparent wind with an autopilot is often not very good with a boat that has good acceleration and can surf some. The apparent wind direction changes so much down wind as the boat speed changes it can have the AP searching all over the place. You might be better off just running to a compass course downwind with the AP, and adjust direction as needed.

Paul L

[witzgall]

Thanks for the input. Any more you can say about how this type of setup might perform on other points of sail? in various sea states?

[Jim Cate]

G'Day Chris,

A couple of points:
All autopilots are subject to failure, both electronic and electro-mechanical. Above deck units like your tillerpilot are especially vulnerable. If you anticipate making voyages of even a few days duration, depending on such a unit is risky. I can attest to the awkwardness of this, since we foolishly made our first bluewater passage (SF to Hawaii) with only an Autohelm 2000 tillerpilot on our Yankee-30 sloop. Two days out of Hanelei Bay on the return trip it died. faced with about 2200 miles of hadn steering, I cobbered up a sheet to tiller rig which got us home, albeit somewhat slower and less directly than planned!. I would REALLY have liked to have a windvane at that time!

Secondly, even if your tiller pilot was hooked up for wind-angle steering, they are typically neither powerful nor quick enough to cope with quartering seas and stiff winds. The sailomat would likely do a much better job. On our previous boat (a retired IOR one-tonner) a home built auxillary rudder type vane steered us for many thousands of miles across and around the Pacific. While it was a bit erratic when surfing, it never got us into trouble... just had a few too many waggles in the wake!.

And as Paul says above, when sailing downwind with an a/p, one usually steers a compass course, not a wind angle course. The wind angle a/p is used to windward. We now have a belowdeck NavMan a/p on Insatiable II and (sadly) no windvane. We do use it in windangle mode upwind... not nearly as good as a windvane, but our best option at this time.

So, for me it would be a no-brainer: keep the Sailomat. I doubt if the weight will make a perceptable difference in performance.

Cheers,

Jim and Ann s/v Insatiable II lying Broken Bay, NSW, Oza

[roger.waite]

Another argument for installing the wind vane is that they can often steer better than tiller pilots when winds increase. So you get the redundancy needed offshore, plus options across a range of wind strengths, directions & sea states. Don't know the Sailomat, but wind vane systems are often fixable when a TP will 'remain dead'. And as you say, you also get emergency steering thrown in. Looks good to me!

FWIW, I agree the weight shouldn't worry a cruiser with a fairly broad stern.