Thursday, April 10, 2014

Sailing to Hawaii - day 10 - Lost a Rudder!

Sent from sea

Weather: [Sunny, nice]

Sailing conditions: [seas are much bigger (3m waves) and choppier, and the ride is 'fun', walking around the boat definitely requires 2 hands]

Food: [Breakfast: Cereal, Lunch: Cheese and crackers, Dinner: Pasta]
Re: our lack of provisioning in Galapagos. We deliberately did all our provisioning in Panama and have food enough aboard to feed us for much longer than we need to reach Hawaii. All we lost by not shopping in Galapagos was some fresh eggs, bread, and veggies - but we can manage just fine without them - we have plenty of tinned veggies, and I can make bread aboard. Please don't worry about us - there is no need.

General Comments: [Kyle had an amazing sight yesterday where immediately ahead of him a huge school of fish leapt from the water, followed closely by about 40 dolphins attempting to catch them. The dolphins act in a team effort to catch and heard the fish, with the dolphins coordinating a leap out of the water themselves.. very cool.

We finally hit the trade winds proper and started to make some good speeds. All seemed well, and we were both happy to have the boat moving properly again.

The big news from yesterday is however, that at about 6pm last night we lost a rudder. Kyle had noticed the steering was a little stiffer than normal, and suddenly we were requiring more turn of the rudder to hold course. Since we are a catamaran, we have 2 rudders, and the other is (at least for now) steering the boat just fine. It is not ideal that we have over 3000nm remaining, and that 'spare' rudder will be tested to the full. We really don't see an alternative to ploughing on. If we head for anywhere else the sailing will be shorter in distance, but just as long in time and more upwind and work/wear on the remaining rudder so on we go, with fingers and everything else crossed.]

Progress: so far we've made [826]nm on this passage and have [3321]nm to go. Last 24 hours we made [193]nm through the water [168]nm over the ground.

Updated after the fact


Pleasant sailing conditions, and Kyle at work on the log and chart plotting

On day nine of our passage, I was sailing along in fairly calm seas when the sea ahead from 30° either side of the bows exploded into white spray. It looked like a depth charge had gone off. A split second later about 50 dolphins leapt out of the water in perfect unison. They all leapt the same height, pointing the same direction and they returned to the water in synchrony. Wow! The Rockettes of the dolphin world. They were fishing and such maneuvers are used to coral, confuse and stun their prey. I cannot think of how such a thing could happen spontaneously if these were not intelligent creatures. They must have someone in the group yelling out the equivalent of “3, 2, 1, NOW”.

Over the next half our or so they continued to do the same with little side groups of about a dozen at a time, occasionally in parallel with Begonia. Amazing.

I hand steer a lot, this is partially since I’m sat at the helm anyway, and partially so I can maintain a feel for the boat (it also saves on battery power to disengage the autopilot). I seem to alternate between phases of thinking the steering is too stiff, and thinking it too loose, causing me to go into states of alternating worry about whether something has ceased or become disconnected. Usually it is nothing, just varying forces on the boat through the water. After the dolphin show, however, it really did fell that it was taking twice as much force to turn the wheel. I turned upwind and slowly coasted to a stop. The steering worked, and at low speeds the wheel felt fine. I decided I was being paranoid again.

A little while later I engaged the autopilot for a minute or two while I stepped away from the helm to adjust a sail. When I turned it off again, the steering felt fine. Yep, Paranoid, that’s me!

I engaged the autopilot again to keep Maryanne company while she made dinner (we traditionally pick a book to read to each other at such times), at this point I noticed something curious: the autopilot seemed to be using twice as much rudder turn/deflection as when I’d been hand steering. This gave me a bad feeling.

Kids, let’s recall the Lift Equation from the first week of flying school: L = CLqS.

Stay with me here, L is the lift, CL is the coefficient of lift, which is approximately equal to surface deflection. q is effectively the force of the moving water and S is the surface area (of the rudder in our case). Therefore if the autopilot was trying to produce twice as much force for a given speed the total control surface must therefore be half. Either we’d lost a rudder or one was disconnected from the steering mechanism.

We stopped Begonia again and tried shining a light on the rudders, but everything is blue down there, including our rudder paint, but we thought we saw them both. As I was climbing into bed later I heard a new noise, a dull clang. I spun around in bed and put my hand on top of the rudder post which is just beyond the foot well. The post was there, and attached to the steering linkage properly, but the rudder was gone. I told Maryanne, who started wondering if it was possibly really this or that, I convinced her to just climb into bed and feel the rudder shaft. It was obvious; our rudders are blade type formed onto a 7ft stainless steel rod that is supported through the hull with two widely spaced bearings. It is a pretty stout arrangement with little play. Feeling the top of the post, now it could be persuaded to lift and raise, we could tell the post had broken above the lower bearing. The clanging I heard was the remaining post banging around lose in the tube.

Well, crap! The good news was that Begonia was steering fine on the remaining rudder. If I hadn’t been ‘that guy’ and we didn’t sleep in that particular berth, we may not have even noticed.

The bad news is that we were a long way from anywhere. Our nearest inhabited land was still the Galapagos (800nm behind), but they have no facilities for hauling out and repairing boats of this type. Mexico was a 1000nm up wind and into heavy seas. If we continued to Hawaii it should be a relatively easy downwind ride, but it was a long way: still 3400nm away (600nm further than our Atlantic passage from Bermuda to Ireland).

We were not sure what caused the rudder post to sever like this. Perhaps an unseen materials defect, hidden corrosion, or just plane cumulative fatigue. This boat had crossed the Atlantic three times before we got hold of it, our concern was the remaining rudder which was also original. While the maximum possible load on it would be unchanged, the cyclic loads would double and there were going to be a lot of cycles in 3400nm. Another tough decision! If the second rudder failed we figured we’d be able to jury-rig a system of emergency steering, but it would neither be fun or terribly efficient.

{Maryanne: Back in Panama, while we were hauled out for bottom paint and general servicing we met another Fountaine-Pajot owner who had mentioned he had lost a rudder in this way. He said he hadn’t even noticed it was lost until he went for a swim one day and saw it was missing; the boat had steered fine without it. The boat yard also said that this was the most common problem that Fountain Pajot boats seem to have. They see several each year arrive without a rudder and needing hauling out for repair/replacement. This persuaded us to check on our rudders carefully and they seemed a little pitted, but otherwise fine. Without a penetrating dye test (which we didn’t have time for before our canal transit) we could never be sure. We figured with the age of the boat we’d consider replacing them as a precaution once we were next in mainland USA, we'd even gone as far as to price the rudders and learned that there was a two month lead time to have them made. All this was now flooding back to us. Would the remaining rudder survive the following 3400nm? It is an impossible thing to estimate. We didn’t have any great options. We had to just hope so.}

We decided to continue on to Hawaii and worked out a crude system for steering the boat using mostly sail trim for use if we did lose the remaining rudder. We could only sail about four different directions with such a method, but by alternating the length of each leg, we should be able to get close enough to the Islands to get us within motoring range when the engines can effectively steer the boat. For the meantime, we would consider every extra mile with our remaining rudder a gift.

We had reached the southern limit of the northern trade winds. The wind direction was consistent but the strength was still variable.

1 comment:

Geoffrey said...

Okay, I'm squarely in the camp of "you can't tell us you lost a rudder, and then not update for 3 days." We are making the appropriate sacrifices to Poseidon for your safe arrival in Hawaii.