How many engines is ideal?

[boathealer]

How ever many engines come with the boat you like the most.

 

[Hippocampus]

Definitely miss 2 strokes for dinghies. Lighter, better hole shot and you can fix it yourself. With an aftermarket fuel filter put in line pretty much foolproof. But sure like the better fuel economy of EFI and ability to get juice off of it for running lights and such. No free lunches in this world. Looked at electric. If cruising just don’t have the runtime, ability to fight a good chop coming in nor range.

 

[Nomad Willy]

Many here wish to just putz around at hull speed like most trawlers.
But the have the “I want everything” mentality. Run slow Run fast. It attracts a lot of skippers. Never mind a lot of serious sacrifices will need to be made to partially do the go fast go slow crowd. But they persist.

For them I think three engines is clearly the best rig.

Hipp,
I don’t .. I have em. Two, 4, 6 and 8hp.
Why settle for something inferior?

 

[rgano]

"Twin engine passenger planes can fly and land with only one engine, I doubt they can take off with one engine only. Each engine must be very powerful."

A modern turbo jet must be able to take off (after V1) on a single engine as well as climb out over obstructions on one.

In addition should one engine fail at altitude over the ocean the operating engine will maintain altitude and keep the aircraft able to complete the flight.

I hear from a professional pilot friend that the smaller twin engine prop planes will fly just fine on one engine if one give out in flight - all the way to the crash site. It seems the most critical time in a twin prop is takeoff. He told me that the recent twin prop crash in Wichita I think it was where the twin just rolled over and into a building at the airport was a loss-of-engine event. There is apparently only one action which will possibly save the lives of those aboard, and it is a split-second one.

Full disclosure: I was once a pilot at age 18 but never flew a twin.

 

[rslifkin]

As far as I know, the "a twin will fly on one right to the crash site" saying comes from mishandling issues. Except for some very underpowered general aviation twins (which really just have 2 half-engines), a twin will fly on one. But if mishandled with an engine out, it can kill you very quickly.

 

[Nomad Willy]

rgano,
I was an ultralight pilot in the 80’s and one of my five ultralights was a twin (Lazair) and the two engines (wing LE) were very close to CL w a 36’ wing span.
After an engine out I flew back to the airport on one but needed a lot of rudder to maintain reasonable yaw attitude. I was 4-5 miles out from the airport at about 2000’ AGL. It was amazing how much adverse yaw the off CL engine caused. But in most people’s minds all my ultralights were crazy dangerous. Of course I never crashed.

To the other extreme I’ve heard many small twins (like Cessna 310’s) actually won’t fly on one engine. I can see why. May be able to better the glide ratio (poor) just a bit. In my mind those planes are more dangerous than helicopters.

 

[Steve91T]

I’m an airline pilot and also fly GA aircraft, small single engine planes. I don’t fly single engine planes in low visibility or low ceiling conditions. If that engine quits I want to have a chance of finding a place to land if I can’t get to an airport. In bad weather you’re in serious trouble.

I didn’t fly many light twins. I do know that there are some that aren’t able to climb out at gross weigh on one engines. Many do though. The 310 with the large turbo engines I believe will.

I have thousands of hours in the Dash 8 that weighed about 40,000 lbs and held 50 passengers. It’s a twin turboprop commuter. It had a lot of power and flew great on one engine, but it was a handful, especially if the failed engine didn’t auto feather.

Jets like the Airbus and Boeing’s are much easier but still require skill and training.

No matter what the plane, the pilot needs to have proper training and be mentally ready for every take off.

About boats.

I have very little experience. Our boat has two mains and a generator. We’ve had a small problem that requires an engine to be shut down. We were able to continue on the other engine. This has happened several times. I really really like having two engines for the redundancy factor along with the added control while docking.

 

[slowgoesit]

As far as I know, the "a twin will fly on one right to the crash site" saying comes from mishandling issues. Except for some very underpowered general aviation twins (which really just have 2 half-engines), a twin will fly on one. But if mishandled with an engine out, it can kill you very quickly.

Not exactly: For instance a friend sold his C-182 because his wife refused to fly an airplane which would "fall out of the sky if the only engine quit" (her words, not mine! Anyway, to appease his wife, and get her to fly with him, he purchased aPiper PA-30 Twin Comanche with recent zero time engines. So there he is, on their first long flight in the American Southwest . . . flying along, and one engine fails catastrophically . . . . . turns out (we did the forensic tear-down of the engines after the . . . well, hard landing) that the reman company didn't torque the cylinders down to the engine case properly, on either engine, and one of the cylinders came completely off after the cylinder head nuts worked free and fell off . . .

Anyway, no problem right? After all it has a single engine ceiling of 5800 feet, right? Unfortunately he was flying over an extensive 7000 foot mesa . . . . There wasn't any "mishandling" involved, but that 2nd engine only meant he had more time to figure out where to plant it, but he WAS going to plant it . . . No amount of "proper handling" would change the physics involved. Anyway, he planted it, on a 7000 foot mesa with mesquite and rocky soil and uneven land. Decided to land gear up to reduce the chances of ground looping or flipping. Did a good job too, as they both walked away shaken up, but uninjured, but the aircraft was totaled . . . Tough luck, but the company who remanufactured the engines ended up buying him a Piper Navajo, a MUCH nicer airplane, and one with a single engine service ceiling of over 15,000 feet! . . . Last I heard from him, several years later, he was STILL trying to get his wife to fly in the new airplane!


Note: then again, you DID mention "Except for some very underpowered general aviation twins (which really just have 2 half-engines)", which the Twin Comanche just may be an example of . . .

 

[rslifkin]

Not exactly: For instance a friend sold his C-182 because his wife refused to fly an airplane which would "fall out of the sky if the only engine quit" (her words, not mine! Anyway, to appease his wife, and get her to fly with him, he purchased aPiper PA-30 Twin Comanche with recent zero time engines. So there he is, on their first long flight in the American Southwest . . . flying along, and one engine fails catastrophically . . . . . turns out (we did the forensic tear-down of the engines after the . . . well, hard landing) that the reman company didn't torque the cylinders down to the engine case properly, on either engine, and one of the cylinders came completely off after the cylinder head nuts worked free and fell off . . .

Anyway, no problem right? After all it has a single engine ceiling of 5800 feet, right? Unfortunately he was flying over an extensive 7000 foot mesa . . . . There wasn't any "mishandling" involved, but that 2nd engine only meant he had more time to figure out where to plant it, but he WAS going to plant it . . . No amount of "proper handling" would change the physics involved. Anyway, he planted it, on a 7000 foot mesa with mesquite and rocky soil and uneven land. Decided to land gear up to reduce the chances of ground looping or flipping. Did a good job too, as they both walked away shaken up, but uninjured, but the aircraft was totaled . . . Tough luck, but the company who remanufactured the engines ended up buying him a Piper Navajo, a MUCH nicer airplane, and one with a single engine service ceiling of over 15,000 feet! . . . Last I heard from him, several years later, he was STILL trying to get his wife to fly in the new airplane!


Note: then again, you DID mention "Except for some very underpowered general aviation twins (which really just have 2 half-engines)", which the Twin Comanche just may be an example of . . .

In my mind, that's mishandling. Flying over terrain higher than the engine-out ceiling without a viable escape path would be a no-go in my book.

 

[FF]

In the Navy I spent some time in a Ferry Squadron VRF 31.

One could choose to fly almost any thing (except choppers) after an open book exam and a flight with an instructor.

I always wanted to fly the C-47 ,,, DC 3 so got Da Book and did the test .

I have been thru lots of manuals but the C-47 that had the instructions for a SINGLE ENGINE TAKE OFF.

I guess if your pacific island was being over run and the runway was long enough it was a valid option , never tried it tho.

 

[Hippocampus]

Interesting discussion but returning to water. Is there anyplace you can get hard numbers on the frequency of PAN, SAR calls, tows or requests for assistance for
single screw set ups v double?
What’s the reality? Some tell me for a well maintained single screw it’s so rare as to not be a concern. Others tell me get home engines are waste of time and it’s frequent enough they wouldn’t be on a single screw out of helicopter range. Also get conflicting opinions on NA v common rail. Some saying if NA fails you have a decent chance of fixing it but if common rail dies it’s usually the black box so get on the horn. Others say common rail doesn’t fail often enough to be a concern.
At present looking at non common rail single screws. It getting harder to find NA but that’s my uneducated preference. My fear is to be in weather with no propulsion.

 

[rslifkin]

Personally, I worry more about a failure with a single in crowded waters near shore than I do further out. Yeah, you can drop an anchor, but it's still pretty easy to end up in an ugly situation with no maneuverability. Further out, you've got more time to deal with the situation, as you're not likely to be 500 feet from a rock and with 8 other boats within 1000 feet.

 

[mvweebles]

Hippo - as the owner of a classic single-screw trawler who is a decent shade-tree mechanic, I personally would not cross an ocean without some sort of back-up. It's not just the engine as potential point of failure, but transmission and prop/shaft. I recall a Deadliest Catch episode where a prop shaft unexpectedly broke. For me, if I wanted to cross an ocean, most practical alternative propulsion would be some sort of significant sail plan. More of a 'get somewhere' vs 'get home' option. But halfway across the Pacific, I'd take it.

Why only crossing an ocean? Practicality. Might be hubris, but I'm pretty sure I would have sufficient notice of an impending failure and, as you note, likelihood I can repair if needed.

BTW - I share an aversion to electronic controls. I love the efficiency and the versatility, but I've been aboard a couple boats with very minor troubles that were difficult to repair. A few months ago I was aboard a friend's 2014 boat with a pair of ~450hp Cummins. RPMs started fluctuating by about 300-500 RPMs. This happened last year. Cummins' tech diagnosed all sorts of replacement items, including a lift-pump and (inexplicably) a rusted turbo. A cracker-jack independent Marine Electrician figured out there was a small quick-disconnect plug with hair-strand sized control wires that had corroded. He found it in about 20-minutes. My point being that a couple of mechanics had given it their best shot that didn't work. Granted, the boat wasn't dead in the water, but having the RPMs vary up/down doesn't instill confidence. I attribute this to electronic controls - and I can't fix it easily (if at all).

Peter

 

[Hippocampus]

So Peter is a 27 hp Yanmar with its own running gear get home a real world solution? The DDs scare me as it’s a big jump for me. I know nothing about steel hull maintenance. I will eventually get out of boating so concerned about resale. Wife wants stabilizers not wanting to transition to a poorly sailing powered craft and have yet to see any steel boat with fins with in our budget. ( she likes steve seaton boats but the financial advisor doesn’t).
Understand the concern about failure in close quarters. That’s the same for sail so been living with that for decades. My thought is then you may lose money but not your life.
We’re not going RTW. More focused on long hops and biannual passages. Even in Maine once you get up to Washington County there isn’t much in the way of support.

 

[mvweebles]

So Peter is a 27 hp Yanmar with its own running gear get home a real world solution? The DDs scare me as it’s a big jump for me. I know nothing about steel hull maintenance. I will eventually get out of boating so concerned about resale. Wife wants stabilizers not wanting to transition to a poorly sailing powered craft and have yet to see any steel boat with fins with in our budget. ( she likes steve seaton boats but the financial advisor doesn’t).
Understand the concern about failure in close quarters. That’s the same for sail so been living with that for decades. My thought is then you may lose money but not your life.
We’re not going RTW. More focused on long hops and biannual passages. Even in Maine once you get up to Washington County there isn’t much in the way of support.

Three or four of the new Nordhavn's I delivered were new enough that I changed the break-in oil precisely at 100-hours which was underway somewhere off the Pacific Coast with the wing-engine pushing us along. It absolutely is a viable get-home system. Slow, but a great system. When PAE did their Atlantic Crossing gig (I forget the name - somewhere around 2004), they required participating boats to have get-home. I think that's responsible. A couple Krogan's participated.

I agree - I don't worry about close-quarters. Worst-case scenario is very unlikely and very unlikely to result in loss of life or even damage. Total loss of propulsion mid-ocean is a serious problem - out of chopper range.

I liken the DD's the proverbial bullet-proof barrel you'd want to go over Niagara Falls. Seahorse and DD have been around long enough that you can get a feel for construction quality. Like almost all builders (though excluding Fleming and PAE), Seahorse are not serious passagemaker/cruisers. The are builders of boats - Willard became this type of builder when their ownership changed hands in the early 1980s. I won't speak of Seahorse or any builder in particular, but this means that some basic items are sometimes inexplicably installed. PAE has a strong user community, many of which are amazingly technical (Dirona guy). They tend to identify and remediate design issues pretty quickly. Not perfect of course, but there's an obvious benefit to buying from a company like PAE or Fleming.

I have very little experience with steel, but I suspect your concern about resale is valid. I was aboard this beautifully constructed steel, paravane-stabilized Dutch trawler 1-1/2 years ago, after a decent refit where quite a bit of rust was repaired. Nothing too serious - just a few nooks and crannies where water pooled and eventually caused rust. I cannot explain why this boat has taken so long to sell - the price is great, she's in great condition, and she's purpose-built for long runs. She's a slightly unusual floor plan - sort of what I call a "Wheelhouse" reminiscent of the old Chris Crafts and Pacemaker motoryachts. It's a great layout. Coincidentally, I was aboard the boat 20-years ago when she used to anchor off my marina in Treasure Island (San Francisco). The boat is a helluva deal at $185k - the only reason she's not sold is she's steel. Hard to believe she hasn't sold, especially in this COVID-driven market (nuts, ain't it?)

Resale is a real concern - you cannot go wrong with a N40. There will be a market for them for the foreseeable future, likely priced fair.

Peter

 

[ljk]

How many engines?

How ever many engines come with the boat you like the most.

Getting back to the original point of the post, NONE! Love my Hobie kayak. Here are the fuel burn numbers for my most recent trip:


FUEL: 3 fried eggs, 2 strips of bacon, 7 oz of tomato juice (my breakfast)!
DISTANCE TRAVELLED: 4.1 nautical miles
RPM: about 40 strokes a minute
NMPG: I dont know how to figure this, suggestions?

 

[Group9]

I would say none. But, then how do you make the boat go?

 

[Hippocampus]

Last transit my boat made.
~2150nm . St.Lucia, lauderdale, Newport. Fuel burn zero.


It was shipped due to covid.

 

[Hippocampus]

So what I’m getting is if you can live with displacement speeds a single screw with a get home is the way to go. Remain surprised there’s no real competition with just one company continuing to offer that set up. This is totally different than the sailboat world where there remain multiple choices (Hylas, passport, HR, Amel, Outbound, Pogo) in production and multiple choices for multihulls as well (Catana, Outremer, Gunboat, Rapido, Neel). Why is that ? Would think there would be a sufficient niche market of long distance power people that it would support LRC models as in the past. Would think you don’t need to be routinely crossing oceans to want that kind of set up.

 

[mvweebles]

PAE have successfully defined Nordhavn as a lifestyle brand who have made investments to demonstrate, test and certify their boats. Heck, they even bought the rights to re-publish Voyaging Under Power to define the space in their terms. Strong marketing approach.

But there are other options, but many with twins. Defever being one in the sub-50' space where they install two small engines. For me, assuming a decent skeg on each prop, if you solve the issue of room on outboard side of engines, twins are preferable to a single with wing.

But in the sub-50' market, when you factor in re-sale, it's difficult to get too far past Nordhavn if you want a serious passage-capable boat. PAE has done a good job of rounding-out their business. Bright people.

Despite all the learned talk in forums like this, I really don't think there are many people cruising their powerboats too far so I'm not sure there's demand. Bahamas, Loop, San Juan Islands/PNW are the big cruising trips. Sure, there are occasional delivery trips up/down a coast, but not a lot of Panama Canal transits and such. Could be that those folks aren't on forums like these - I know of one couple who have been cruising their Willard 40 from Maine to Alaska (several times) for years. They check in with the Willard Group from time to time, but it's rare.

Back to the topic - one engine is all that is needed. But if you want to do serious crossing, two are needed. At least a wing. Preferably twins. That's my opinion. That said, I do agree that if another builder took the time/effort to install a wing-engine, they might be on to something. North Pacific? Helmsman? Other?

Peter

 

[Art]

Getting back to the original point of the post, NONE! Love my Hobie kayak. Here are the fuel burn numbers for my most recent trip:


FUEL: 3 fried eggs, 2 strips of bacon, 7 oz of tomato juice (my breakfast)!
DISTANCE TRAVELLED: 4.1 nautical miles
RPM: about 40 strokes a minute
NMPG: I dont know how to figure this, suggestions?

Think you mean: NMPFa's... "Breaking wind" after breakfast may offer propulsion assistance; therefore could [somehow] be measured!

 

[Hippocampus]

Yup Peter they’re very smart. The Outbound owners group is open to all. Every wart and pimple is discussed endlessly by the owners so prospective buyers know exactly what to ask about. What repairs, upgrades and even which yard does the best job fixing those faults. Fortunately the faults are minor as they’re extremely well made boats. Although there’s the Nordhavn Dreamers it’s pretty much useless. Very few actual owners discussing the same kind of stuff. To get that kind of lowdown you need to be on the owners site which is closed to non owners. That makes it hard when you’re in the position of trying to choose which one to buy. Very clever.

 

[mvweebles]

Although there’s the Nordhavn Dreamers it’s pretty much useless. Very few actual owners discussing the same kind of stuff. To get that kind of lowdown you need to be on the owners site which is closed to non owners. That makes it hard when you’re in the position of trying to choose which one to buy. Very clever.

That happened in the early 2000's. I forget the actual issues, but Nordhavn/PAE started to take some flack from pissed-off owners, probably due to construction delays and such. Back then, the Big List was Trawlers & Trawlering (there was a prior name, but I can't remember it). I recognize a few of the names on this list from back then. If I remember correctly, the first Nordhavn list was started by an owner. Pretty quickly, PAE started the Owners Group that was (and still is) closed to all except owners, presumably so they could control the messaging. I liken it to Harley owners who have the attitude that just because they woke-up on 3rd-base means they must have hit a triple. Way too clubby for my tastes, but they are a good boat, and the owners I've met are great. And I also have to say that Dan Streech and Jim Leishman treated me professionally and respectfully when I was delivering their boats so no argument there either. I just hate the yacht-club snootiness - brings out the Groucho Marx in me ("I wouldn't belong to a club that would have me as a member").

I've moderated the Willard Boat Owners group since 1996 or so - it's open to all (https://willardboatowners.groups.io/ for anyone interested - we only get a handful of posts a month these days, but tons of files). Before Willard ceased production in 2002 or so, some of their execs were on the list. They were extremely uncomfortable with some of the discussions as some was not flattering. But in my opinion, it's important for these lists to be wide-open. We're not discussing the secret formula to Coca Cola.

Sorry for the hijack. Somewhere there's a point about number of engines.

Peter

 

[Hippocampus]

That’s alright I’m used to being either the poorest or richest person in the room. A lot of all hat and no cattle in this world.

 

[Giggitoni]

Getting back to the original point of the post, NONE! Love my Hobie kayak. Here are the fuel burn numbers for my most recent trip:


FUEL: 3 fried eggs, 2 strips of bacon, 7 oz of tomato juice (my breakfast)!
DISTANCE TRAVELLED: 4.1 nautical miles
RPM: about 40 strokes a minute
NMPG: I dont know how to figure this, suggestions?

Forget the eggs, bacon, and tomato juice. If you had four pints of beer for breakfast you’d get about 8.2 NMPG.

 

[BandB]

Last transit my boat made.
~2150nm . St.Lucia, lauderdale, Newport. Fuel burn zero.


It was shipped due to covid.

Wifey B: Oh, I find it so sad having to ship it instead of making that trip on it.

 

[Hippocampus]

Coming home is usually so much easier than getting there. Find the nicest awa. Hit the stream wherever. Ride it home. Think you were being sarcastic and that’s fine but yes we did miss bringing her home ourselves. Some enjoy the destination. Some the voyage. Some both.

 

[Fr8dog61]

Twin engine passenger planes can fly and land with only one engine, I doubt they can take off with one engine only. Each engine must be very powerful.

I see plenty of go fast opencockpit large fishing boats with 4 outboards, those people want speed. It all depends what kind of boating you want to do, what you can pay for.

Actually, they can take off with one. It is required by regulation. I fly a twin engine airliner (Boeing 767). For the record my boat has a single engine (Mainship Pilot 30)

EDIT: Sorry after posting I see others have beat me too it!

 

[FF]

"So is a 27 hp Yanmar with its own running gear get home a real world solution?"

Reading the many posts on fuel burn it seems many folks have a modest , under 2 GPH consumption at a Knot or so under hull speed.

This with the usual TT engine that burn would equal 30-40 hp.

If a wing engine was used as a propulsion engine with its own shaft, fuel tank, and in particular a Luke or similar prop it should give perhaps 5K or more.

A folding racing sail prop does not push a bog heavy boat very well, the Luke does

Wing engines have a bad rep , mostly because there not used enough to be reliable.

The EZ cure for that would be for the get home to also perform as your gen set.

If the boat made only 100 to 125nm per day in modest conditions with the emergency propulsion , that might be enough , as you should have plenty of fuel.
Automatic Feathering Propellers, P. E. Luke. Full Service ...

www.peluke.com › marine-hardware › boat-props

Automatic Feather Propellers, P. E. Luke. Each propeller is custom crafted from a heavy duty aluminum bronze alloy. .

 

[O C Diver]

Interesting discussion but returning to water. Is there anyplace you can get hard numbers on the frequency of PAN, SAR calls, tows or requests for assistance for
single screw set ups v double?
What’s the reality? Some tell me for a well maintained single screw it’s so rare as to not be a concern. Others tell me get home engines are waste of time and it’s frequent enough they wouldn’t be on a single screw out of helicopter range. Also get conflicting opinions on NA v common rail. Some saying if NA fails you have a decent chance of fixing it but if common rail dies it’s usually the black box so get on the horn. Others say common rail doesn’t fail often enough to be a concern.
At present looking at non common rail single screws. It getting harder to find NA but that’s my uneducated preference. My fear is to be in weather with no propulsion.

I think Charles Lindbergh's approach makes good sense. If you're risk of failure (with catastrophic results) is extremely small either by time or percentage, there is reliability in simplicity of a single engine. As time or percentage increase, the law of probability catch up with you.

For coastal cruising, I rationalized that single engine failure would likely be life threatening <1% of the time. As such, the odds were decidedly in my favor. If I were traveling to remote locations without a reasonable expectation of help in 24 hours, or crossing oceans where weather could compound the problem, the risk factor warranted a second form of propulsion. Eventually I came to the conclusion that 2 identical drive trains made more sense than a single and a wing engine.

Ted