Our boat, a single engine displacement trawler, bought with eight years of age on her, was designed with a get home capability, by belting a 25 horse power electric motor, driven by the 33kw generator, directly to the drive shaft. This delivers more than four knots of forward motion in calm waters; we have never tested her in rougher conditions. I was glad we had the capability when the engine quit quite suddenly after one of our more boisterous passages, just as we entered the reef strewn bay at Rum Cay in the Bahamas. We immediately dropped the anchor, got secure, but with a lot of roll. We called the marina, where we had dinner reservations, and explained the situation, and while we all agreed it was probably a clogged fuel filter, they offered to lead us into a spot among the reefs, where we could more comfortably attack the problem. We explained the pitfalls of this system, no speed control, no reverse gear, just an on or off, full speed and coast to a stop situation. Another difficulty was communicating from the commander (me) at the wheel, to the master (Dave) in the engine room, when to engage, and disengage the power. All went well, including the tactic of turning the wheel hard over a couple of times to hasten the slow to a stop procedure, once we got within striking distance, literally, of the reef.
It is possible this problem could be overcome, by putting a manual transfer switch on the bow thruster motor, so I could use that control at the helm station to engage the get home motor in forward, reverse, or neutral. Both motors are the same size, it should work, but since we have only used the get home motor once in ten years, we have tended to ignore it.
Is it worth having this equipment? Dave would rather use the space for a second smaller generator, for the many hours when the other one is seriously underloaded. Our get home method, like all secondary drive systems has its pitfalls, as I mentioned above. It is certainly of no use in tight situations, like in a harbor, but then, the dinghy tied along side or a tow would be an option. It is out in the open that it could be a blessing, helping us keep the boat in a more comfortable direction, while working, and getting us within reach of other help. Of course it would be worthless if the problem was in the shaft or prop. As I said, it has been used only once in what is over 30,000 miles, and then it was for comfort, and a chance to try it out, neither really necessary, so is it necessary? You be the judge.
