Advice on handling a twin engined boat with one engine in a narrow channel

[bowler]

Hello all,

Firstly, congrats to all you English boaters who are back on the water. Sadly here in N.Ireland we are still housebound but hopefully that will change soon.

I have a Fairline Corniche 31 with twin TAMD41s. Assuming one engine failed, it is possible to continue on the second. However, I have found that a significant amount of steerage is lost when using a single engine, particularly when moving from a stationary position. Depending on which engine, the boat heads immediately for port or starboard until enough speed it built up that the steering eventually has some effect and the boat straightens out and I can regain reasonable control.

Where the boat is berthed (on a river), there are narrow channels (none of which are straight) into lock gates that we have to navigate before we can get to sea. In a scenario where an engine failed on one of these narrow channels I can't imagine being able to continue on a single engine without losing enough control to keep the boat off the shore, or the shallows, on either side. At least initially.

Any thoughts on how disaster could be avoided in this situation? Could a small portable trolling motor be mounted on the swim platform to provide even steering, or counteract the initial push created by the one remaining prop and keep the boat straight? Does one exist with enough grunt? Obviously wind and tide are a factor as well.

Hopefully this never happens, but if it did I 'd like to have a plan in mind.

All thoughts welcome.

D

 

[markc]

Manoeuvring a twin engine boat on a single engine is never going to be easy, especially shaft drives as you need water flowing over the rudders to give you steerage. I can't see that a trolling motor is going to be any good, especially as you are likely to lose an engine in a un-planned way. The best option would be a bow thruster to quickly correct slow manoeuvres. Practice too so that you are more likely to be confident in your ability on one engine. Also practice using warps to spring in or out of a mooring on one engine.

 

[atol]

the boat might actually steer better in reverse if only using a single engine at a speed of less than a few knots as the rudder will then have clear water passing over it

 

[jrudge]

The other thing to bear in mind is when you use a single engine boat it is quite normal to apply large short burst of power to get water over the rudder and move the stern.

My only experience is hire boats on the thames but being heavy with the power ( the engines are also small to be fair) was the main way to get it to do what you wanted if slow / stationary. Pretty much the opposite of a twin engine boat that never really gets much above idle.

 

[tico]

You may wish to consider dropping the trim tab fully down on the side of the functioning engine, with the opposite side fully lifted.
Thus creating drag to (partly) counteract the thrust of the prop.

 

[Rocksteadee]

3 things:
practice
practice
practice

 

[Mr Googler]

strong deck on those fairlines.....should have no problems bolting that to the bow

 

[Rocksteadee]

As mentioned, go astern.
The principle of getting more control pulling a bit of string rather than pushing it.
Little tip I picked up.
on out drives the prop in astern can “pull“ the stern In to the direction required. This does not work with a shaft drive as the force of water against the rudders in very minimal. So have the helm to the side that you may want to steer the stern, build up a bit of momentum going astern (walking speed) when you want to steer the stern away from an object, shallows etc, give the throttle a quick burst ahead. This will not take you forward (although it may take off all the momentum astern but it will kick the stern in the sideways direction you want, as there is a large thrust from the prop acting on the rudder

 

[sharpness]

A good tutorial vid from motor boat and yachting, how to turn using one engine.

 

[Rappey]

3 things:
practice
practice
practice

Probably the best advice. You could find some empty moorings and practice manouvering around them ?
It can't be worse than an along side tow with a smaller boat where the thrust is even more to one side.
There are certainly limitations but experience could tell you if you can carry out the intended manouver safely.

 

[Robin]

We ran out of fuel on port tank/one engine and continued under the starboard engine at low revs/slow speeds with few problems as far as the fuel berth some 8 mls away, did use bow and stern thrusters when going alongside mind but not underway.

 

[Gemini]

Worth also noting which engines drives the power steering pump ,as if thats the failed engine steering will be more difficult ,

 

[Rocksteadee]

Also note that technique differ for out drives or shaft drives.
Out drives have the ability to push or pull the stern of the boat in the direction they are steered as it is the direction of thrust which is moved ie. props
Shaft drive, the props only thrust to the stern and it is this thrust acting on the rudder which gives change of steering direction.
However there is some steering effect from prop walk or paddle wheel effect as described in the Mendez vid.
This effect is more pronounced on shafts, less so on outdrives and almost negated on duo prop.
Port prop will take the stern to port and Stbd to stbd when ahead and opposite when astern.
The reason in the vid John could not turn to Port using Stbd engine
Interesting concept for which I will follow my own advice and practice, practice and practice

 

[omega2]

SLOWLY, SLOWLY, and as suggested practice

 

[oldgit]

lots of fenders.

 

[dava]

Yes you can't beat practice, as already mentioned it can be fairly easy with outdrives but more tricky with shafts. What I found on my old catamaran was to go steady and when approaching a wall / pontoon head in with the operating engine on the outside so when you have to give it that burst astern it will naturally pull the stern in straightening you up with your mooring, if possible you want to be drifting into the mooring from a long way off to avoid the power altering course too much.

Navigating through a tight channel I would just run very slowly, hanging a large bucket overboard on the operating side can help to balance things out a bit too.

 

[bowler]

Hello all,

Thanks for replies.

I should have mentioned that I am on shafts. Also, I am not worried about docking with one engine, I have plenty of fenders and have done it a few times already. Its drifting onto rocky shallows in long, tight river channels that concerns me, no amount of fenders will save me then.

Every boat I have driven, and owned, has been single engine, but the initial prop walk/understeer on this is waaaay more pronounced when getting underway on one.

Suggestions!

Bow thruster - certainly, if I had one! Not enough money in the kitty for that.

Practice - yup, that makes sense, though difficult to recreate the shape and width of the channels in question but I do agree that practice trying to keep her straight, at super low speeds, on one engine is sound idea.

Going astern - Nice idea and something I wouldn't have though of, but even if it did work, I would never get the boat turned around on the channels in question. Some parts are less than 30 feet wide. Maybe I could head back going astern, turn in wider water, and then continue on my journey if the boat proves manageable? (We will def be on the flybridge for that one...)

Dragging a bucket - Great idea, like a sea anchor. Makes perfect sense. This has got me thinking, as there are normally at least two of us on board, what about a good set of oars! I have them on the ski boat, why wouldn't they work on this? Or at least prove useful in conjunction with the ideas above.

Or, rob the car and put FARSOs plan into action...

Cheers folks - great food for thought.

Happy boating over the weekend (I'm not jealous - I swear).

D

 

[Deleted User YDKXO]

One technique that has worked for me in the past is this and I dont pretend it is easy or quick but you should make forward progress if there isnt much tide or wind running against you

Lets assume your s/b engine has failed and you are in the middle of the channel. Put the rudders hard over to s/b and put the port engine astern for a short burst. That should turn the boat until it is facing across to the port side of channel at an angle. Put the rudders hard over to port and put the port engine into forward. The boat should then make forward progress in an arc until you end up facing the s/b side of the channel. Before you get to the s/b side of the channel, turn the rudders hard to s/b and go astern on the port engine. That should turn the boat again until it faces towards the port side of the channel. And then repeat

As I said it will be slow progress and it might take you several attempts at moving forward before you get the hang of the angles. It would be wise to get the anchor ready for deployment such that if you got out of shape and found yourself drifting uncontrollably towards the limits of the channel, you could just drop the hook and hope that it holds you before you go aground

Frankly the reality is that you would probably be better off hanging around until somebody can give you a tow to the lock or ask the lock keeper or marina to send out a dory to help you

 

[dava]

Going astern will not help you on shafts, @Deleted User is right using a quick burst astern to effectively oversteer then steady ahead with helm hard over is a sensible way to go although will be slow progress, your absolute best strategy is to get moving steadily when you have plenty of room and then you should have sufficient control through the narrow channel at slow speed.
On a related note there's other things you might want to practice for, I've had to return to dock before with both rudders jammed hard to port after a steering failure, must of looked interesting coming up the Tyne sidewards.

 

[Hurricane]

Jons video is really interesting and, as usual, very well produced.
It was 15 years ago when I last did that exercise and I had forgotten the technique of turning into the driving engine.
It makes much more sense now that I have much more experience.

And on the bigger boats, the rudders are driven from a separate pump so it doesn't matter which engine you loose, the rudders will still work.

My problem last autumn was that I lost the entire steering system mid way across to Ibiza.
In that instance, we only had the engines to steer - loosing an engine under those circumstances would have been interesting.
It was frightening enough not having any helm!!
These things are all there to test us though.
And it is "resolving the unknown" that gives me the biggest kick.