Secondly, unless it's some of those much larger boats, the twin engine rooms I've seen often have areas of one or the other engine that are hard to get to.
I've really been enjoying our uncluttered ER with the single and lots of space on both sides.
Keith, you have it about right and your suggestion is pretty much what I do. If the boat gains enough speed in reverse then the rudder will become effective. I don’t go hard over as then the rudder works more as a brake in reverse than a rudder (in reverse at least). What I find is that as my boat is far enough out of the slip that I can start to move the stern to starboard, I often have just enough speed to make the rudder effective. This is the situation where it would be hand to be able to turn the rudder quickly from one position to another.
What I have found is that I do best to leave the rudder in the neutral position as I back up, but then move the rudder to port when I want to pulse forward power to move the stern to starboard. The neutral rudder tends to resist the port propwalk much better than a starboard rudder position.
Of course, the simple solution is to just use the bow and stern thruster that I have to take care of it. However, I prefer to have a technique that isn’t dependent on the thrusters as a matter of course. I’ve been in the situation where my thruster has failed.
Some years ago we were touring a few ATs your size and larger at the AT factory. My wife's comment was how tight the ER space was in comparison to our DeFever with twins. Not a knock on ATs though, nice boats.
So you will spend tens of thousands for bow and stern thrusters in order to NOT use them? Is there something I am missing.......?
I prefer to have a technique that isn’t dependent on the thrusters as a matter of course. I’ve been in the situation where my thruster has failed.
Most of the worlds fishing vessels operate on a single diesel, and work far offshore with few failures.
The key is maintenance and a good understanding of the equipment, and of course, it’s proper operation.
Unfortunately, the same statistics do not apply to the recreational sector, so twin installations may just double the chances of failure!
If the fishing/shrimp boats if worked on are any evidence, it’s a wonder I haven’t died a thousand deaths.
I fished offshore for forty years on boats with a single diesel and see no need for two. The "spare" engine theory doesn't work in my mind, for the expense of having a second engine you could be towed in several times. The maneuverability issue is more easily addressed by learning how to handle a boat, I've run single screw boats up to 180 ft. in confined spaces and it's not really all that difficult with adequate crew.
That seems very correct... "... single screw, 180 ft.; with adequate crew." I can well imagine that when you get up to the 180' range, unless you have twins and untold number of powerful responsive thrusters in various locations - even boats with plenty of self-sustainable single hand pilot maneuverability should have adequate crew at hand.
So, it has been "decided" that on commercial fishing, large cargo vessels and workboats a single is recommended. Further on smaller boats a single pretty well fills up the ER.
Oh oh, twin powered vessels of all shapes and sizes are selling like hot cakes. Boat magazines and sales events showcase multiple engines. Possibly there is a disconnect between this thread and the current recreational boat world.
There may be a "disconnect" between this thread and the recreational boat world but there isn't one between going to sea and sound seamanship.
Just want to throw this in...
Depending on the arrangement of many twin engine boats [size, placement, product capabilities or lack of capability... etc... as well as the speed desired] it is not difficult to run on one engine at time in the lower speed range. There are numerous variables that come into play... however... just because its twin screw doesn't mean both screws need to always run consecutively.
I actually disagree with that Art. Running a twin on one is only an indication that one has the wrong boat. The only two reasons for running on one is that the other quit or you’re trying to make an unsuitable boat into a suitable boat by running on one so the fuel burn is less. IMO you can't afford that boat. Just my opinion.
I actually disagree with that Art. Running a twin on one is only an indication that one has the wrong boat. The only two reasons for running on one is that the other quit or you’re trying to make an unsuitable boat into a suitable boat by running on one so the fuel burn is less. IMO you can't afford that boat. Just my opinion.
Some boats CAN gain by using one engine.
The fish boats that tow nets require large HP to function.
On a long transit removing one prop will allow the boat to procede on one engine quite well and save fuel and engine hours .
For most folks the hassles with transmissions and a free wheeling prop, or the difficulty in locking a prop ., is seldom worth the effort.
Some boats CAN gain by using one engine.
The fish boats that tow nets require large HP to function.
On a long transit removing one prop will allow the boat to procede on one engine quite well and save fuel and engine hours .
For most folks the hassles with transmissions and a free wheeling prop, or the difficulty in locking a prop ., is seldom worth the effort.
I'm sure locking a prop so that freewheeling does not hurt transmission can become PIA if done often and not having specialized, easy to actuate shaft-lock apparatus.
Luck for us locking is not needed. BW Velvet Transmissions our Tolly has is fine for freewheeling without hurting it; especially at the low speeds we travel when purposefully using just one engine. In addition, I alternate engine use on regular basis during the very slow cruise to keep use-hours similar as well as to not constantly let just one trany experience free wheel stress... no matter how OK it is according to BW experts.
And... because freewheeling is no problem... the freewheeling prop causes less drag than prop locked rigid in position. Which is another assistance to getting near 3 nmpg at 5 nmph, on single engine use, slow-cruise in a planing boat that can also easily cruise at 16 to 17 knots - or above.
Just for reference my 38' dragger weighing 50,000 lbs would use less than a gallon an hour at 5kts.