End to Flanagan's Arctic transit attempt?
by Adrian Flanagan on 18 Jul 2006
Adrian Flanagan and Barrabas Alpha Global Expedition
Barrabas is injured and the problem could spell the end of any attempt to transit the Arctic this season.
After several days of windless conditions and heavy cloud cover during which the wind generator and solar array were not able to generate much charge, the batteries had become depleted. I decided to run the engine in neutral so the alternators could charge the battery banks. This was also an opportunity to engage the engine and get the propeller turning to ensure all was in order. With the Arctic phase looming, it is essential that the engine and drive are in tip-top condition.
Up in the cockpit, I eased the throttle forward to engage. I knew immediately that we had a very serious problem. The clanking coming from the propeller shaft was horrendous - metal on metal. I left the drive turning for thirty seconds, listening intently to better make a diagnosis. With the engine back in neutral, I pondered on what might have happened and how it could have occurred. The date was Monday 10th July.
Last summer, during the refit, I paid particular attention to the engine and drive, anticipating the high mechanical demands of navigating in ice. A series of heavy duty fuel filters were installed and a new day tank. Having lost the engine because of dirty fuel on the delivery trip from France the previous April, I needed to ensure that the fuel reaching the injectors was as clean as possible.
The propeller shaft was removed and inspected. Crevice corrosion was found, in one spot penetrating a third of the way through the shaft. I decided on a replacement shaft and took the task to a small outfit called SeaTech in Cowes. Two weeks later, I collected the new shaft and returned to the boat yard to install it.
The propeller shaft is transmitted through the hull via a stern tube, which is part of the hull construction. At the inboard end, the shaft is linked to a coupling which in turn is connected to the transmission. Cutless bearings at the inboard and outboard ends hold the prop shaft firmly within the stern tube. A cutless bearing is a sleeve of about eight inches in length which forms a very snug fit inside the hull stern tube and through which the prop shaft rides, also in a reasonably snug fit. The cutless bearings prevent lateral movements and assist the shaft to spin true.
With the help of a couple of workers at the boatyard, we tried to slide the prop shaft through the newly fitted outboard cutless bearing. We could get the shaft about half way in but no further. Eventually I called a stop and took the shaft to a marine engineer to test for alignment. As I suspected, the 'new' shaft was badly bent - not so much as could be seen with the naked eye but sufficiently to ensure that it would never spin true. I took it back to SeaTech, who protested quite unpleasantly. Eventually, it was straightened (apparently). I managed to fit it, but noticed that the shaft was protruding seven inches or so from the hull whereas the original shaft had the propeller much closer in. With the refit behind schedule and Barrabas needing to go back in the water and taken to a yard in Southampton for her electronic fit-out,
I didn't insist (as I should have done) on the shaft been cut down. SeaTech were adamant that it was the same length as the original, so perhaps the sea fairies had visited Barrabas during the night and shifted the engine back by an amount equivalent to the new shaft's protuberance!
Sitting in Barrabas's cockpit in the northern Pacific, I thought back to all this. I believe that the centrifugal force of the propeller (which is solid Stainless Steel and weighs 15 Kg) is flexing the over-long portion of the shaft extending beyond the aft cutless bearing, so that the shaft itself, instead of spinning true is describing a rotational arc, all the while trying to describe an ever increasing circle as it spins. This would cause the cutless bearing to wear away very quickly at its aft end and could well have been 'corkscrewed' out of the hull tube and along the shaft until it met the leading face of the propeller at which point it would begin to get chewed up like a piece of meat being fed into a grinder.
Back in Honolulu, I met a lovely guy called Les Vasconcelles. He has a business cleaning the undersides of boats and he kindly offered to scrape Barrabas clean of her dense beard of gooseneck barnacles for no charge. He surfaced at one point to tell me that I had fishing twine wrapped around the shaft. He had cut some free and handed it to me. My first impression was that the warped, moltern looking mass of plastic was not fishing twine. Les also mentioned that the prop 'was a bit loose'. Up to that moment, there had been no audible sign of anything amiss, though the engine had only been engaged while I was manoeuvring
out of the marina at the start of the voyage and driving into the Waikiki YC. Prior to that, I had perhaps put on 30 engine hours getting to and from various boatyards during the refit. Because of this absence of audible symptoms, because the shaft was new, because I had had the engine realigned, because the cutless bearings were new, I simply did not put two and two together.
I got up from my seat in the cockpit and went below to have a look at the piece of stuff Les had given me, which I had in the chart table. I examined it carefully. The curve of where it fitted round the prop shaft is clear, the inside surface is discernibly one piece and not a lot of fused strands, it is grey in colour - the same colour as the cutless bearings. I went back on deck and sat examining and re-examining the bit of mushed nylon. There was no doubt - I didn't have to go over the side to inspect the prop - the aft cutless bearing had extruded, the shaft was no longer held firm and I had effectively lost the use of the engine.
The Arctic phase cannot be countenanced without the engine. Conditions are often windless and in the pack it is best to assume the ice is concrete - so a degree of tight manoeuvring is necessary to avoid scrapes and collisions which would be impossible to achieve under sail.
The fickle winds I have experienced since making my turn at the antipodal point have put me nearly 800 miles behind schedule. My deliberately conservative sailing tactics to avoid over-stressing the rig have eroded boat speed by perhaps one knot. Taken together with the delay caused by the emergency stop in Honolulu and it's touch and go whether I can make the Bering Strait in time to have a sensible crack at the Northern Sea Route. Now this - I could not help but lower my head into my hands. With an effort, I overcame the rising mist of
tears...this was no time for emotion. Barrabas was hurt. It is true that
her hurt is my hurt, but I had to be pragmatic, assess the problem in the context of the rapidly shrinking time window and decide upon an appropriate solution. I let the predicament mull for 24 hours.
The fix is straightforward, but Barrabas must come out of the water. The major potential complication is that with the prop shaft unsupported aft, it may have become bent in which case it will need to be straightened or a new shaft fabricated. All of this eats valuable time.
Do I go into a Russian or an Alaskan port? After consulting my various pilotage books, I have decided to put into Nome on Alaska's west coast, self-styled 'metroplois' of NW Alaska...'There's no place like Nome' - their strapline, not mine. There is no language barrier, parts are likely to be more available and customs procedures less involved.
The settlements that dot the western and northern Alaskan coasts are small and remote, but Nome is the largest of them with a population of 3,000. With an action plan outlined, I called Louise. She contacted Joy Baker, the harbourmaster in Nome who provided a number of contacts. There is no marina per se, nor public haul-out facilities.
Tom McGuire who runs the Norton Bay Seafood Company, who spends half the year
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