Anyone else run on just one Iron Jib?

[Philip St1]

The 'running on rails' response was from the salesman, of course.

Having to use a little rudder doesn't seem like to big a price to pay for using less gas on a passage. The salesman did not comment on how it was to maneuver around other boats. He probably didn't have anything good to report.

I had a centrally located (both side to side and fore to aft) 9.9 Yamaha not set up to steer on my 34 foot self designed, self built catamaran. It would not do the corners very well. My new boat (still settling on the exact details as we speak--I love the design process, and now with the Internet, there is so much more information for me to use--like this forum) will have twin outboards (for low cost) to get the maneuverability that I didn't have before.

[colemj]

Originally Posted by Cheechako

There is no doubt that you will need the helm turned a little if running on one engine in flat water and not sailing. If that's "like it's on rails" sobeit!
Also, having had to maneuver a cat on one engine while heading up island to get the other fixed.... I can tell you... it's pretty scary in proximity to other things. You have to plan ahead... you wont turn thru the wind if there's much at all at slow sped so you have to think it thru so that you always have room to turn downwind etc...

I set ours up with counter-rotating props (one left and one right) and placed them so that the prop-walk counteracts the distance from center. The counter helm needed when running one engine is negligible - maybe 1-2 degrees.

Doesn't help in a close situation on one engine, though.

Mark

[markpierce]

Seems a shameful waste to have a boat with two main engines but elect to routinely use only one at a time.

[2Hulls]

Originally Posted by markpierce

Seems a shameful waste to have a boat with two main engines but elect to routinely use only one at a time.

Actually, most of us don't use either engine most of the time.

[StuM]

On your average 40-45ft cat with 40-50HP diesels, motoring in the 6-7 knot cruising range on alternating engines should see at least 15-20% fuel saving and 50% less engine hours compared to running both engines at lower revs to achieve the same speed. It will frequently also put the running engine into the preferred 70-80% of max rpm range instead of the sub 60% range which is not so good for the engine over long periods.

[Helia 44]

Originally Posted by markpierce

Seems a shameful waste to have a boat with two main engines but elect to routinely use only one at a time.

Really Mark? I would like to hear the logic... It seems to me to run both is a waste, when one will do the job most of the time...

Also, it seems an environmental waste of fuel, when I can do 6.5 to 7 on one motor, and when I run both only go about 9.. ????

Also, by alternating engines, I could have a lifetime without replacement. I mean one might do 10 years, alternating go 20? The only time I really need both for sure in the harbours, the twin screws out over 20 feet apart allows you to pivot her on a dime. I mean you really need both for control in tight conditions, OR if you were in a real hurry for some reason..

Mark, I am very open minded, I feel blessed by having a whole spare engine when cruising in light air and motor-sailing.. So, no disrespect intended, just curiosity: Please indulge me and tell me how you think it is a waste, as I love it!! It is like having money in the bank you can really use in a pinch!!!

[markpierce]

It is sort of like purchasing/maintaining/towing another (undoubtedly smaller) vehicle in case the first one breaks down. I suppose one can't be too cautious. ... Come to think of it, most all liveable power boats have two engines (not counting gensets) largely because they want duplication. But a catamaran with sails and two engines? That's like having two backups. That's what I call risk-avoidance, at a cost.

[2Hulls]

Originally Posted by markpierce

It is sort of like purchasing/maintaining/towing another (undoubtedly smaller) vehicle in case the first one breaks down. I suppose one can't be too cautious. ... Come to think of it, most all liveable power boaters have two engines (not counting gensets) largely because they want duplication. But a catamaran with sails and two engines? That's like having two backups. That's what I call risk-avoidance, at a cost.

The reality is that our boats would not be maneuverable with only one engine, unless it was on the centerline. Putting it there (although a few designs have done it) poses design compromises that are not reasonable. Call it what you want, but it's the reasonable design conclusion.

2 Hulls Dave

[Helia 44]

Originally Posted by markpierce

It is sort of like purchasing/maintaining/towing another (undoubtedly smaller) vehicle in case the first one breaks down. I suppose one can't be too cautious. ... Come to think of it, most all liveable power boats have two engines (not counting gensets) largely because they want duplication. But a catamaran with sails and two engines? That's like having two backups. That's what I call risk-avoidance, at a cost.

Yea, TwoHulls said it well... But anyway Mark, this is not about waste or risk avoidance. No offense, but you must be a monohull Person? Dreaming of a Cat? I can relate, but no waste here with two engines, for (as I think I have already said) you need them both in the harbours and tight spots - you need both engines to manoeuvre. After much study, I have come around to Cats as I only aspire to the east coastal cruising of Australia.. Most of that and the Great Barrier Reef, is most suited to a cat. My style of monohull just has too deep of draft, this is definitely Cat country... Really, more than half of the good places would be out of reach to a deep draft monohull, especially the ones I like..

And, free to admit, I have motored around the islands quite happily at sailing speed when there is little or no wind. This is shallow draft Cat country. Plenty of slips, whole marinas designed with double slips like a side tie for two monohulls or a single Catamaran.

Best regards, Helia