improving steerage in reverse?

The shark dies if it stops moving, be like the shark, plan to not stop moving until you're in the berth. Your boat handles well when you're going forward, with water flowing over the rudder. Your boat handles ok when moving astern, with water flowing over the rudder backwards. Just plan to not change from ahead to astern in confined waters, and practice keeping enough momentum to keep steerage way. It takes forever to re-gain flow over the rudder, so plan to only go ahead to astern when you have space and time, so not in the confined aisle of the marina? This approach works with folding props which take ages to gain momentum in astern, it works with long keels which seem to take forever to get water flowing over the rudder.

You will have to use warps and imagination to get the boat lined up to leave a tight berth, you might have to dig deep into the toolkit if you have to change your plan at short notice, if for example someone pulls out of their berth without looking when you're already committed to backing up the length of the marina aisle, but otherwise it reduces risk, shouting and general amusement of onlookers.

Never liked bow thrusters for this, they are usually underpowered, so they can only help control the boat in lighter winds when they're not really necessary, by the time you get enough wind to make them useful, most don't have the grunt to actually bring the bow into the wind anyway, while the main engine and a huge rudder can overcome most windage, as long as you keep the water flowing over it by keeping her moving. Bowthrusters are good for getting the boat into impossibly tight berths, but sometimes not so good at getting you back out of them once conditions change.
 
westernman said:
You have it good.
My boat does not gain steerage in reverse at anything less than 4 knots in dead calm conditions.
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AntarcticPilot said:
The bottom line is that going forward, the rudder deflects the propwash, enhancing the steering effect, so that going forward you can almost turn in the boat's length, and can turn while almost stationary. In reverse, only the flow of water past the rudder is deflected, and at low speeds, this may be insufficient to overcome prop-walk and/or wind. So in reverse, you need to have steerage way before the rudder has any effect.

A technique I have found to work on my Moody 31 (fin keel, rudder on a skeg, conventional stern gear with the propeller just forward of the rudder) is to centre the rudder, give a burst astern at a high throttle setting to get her moving, engine in neutral and THEN steer. This works about 9 times out of 10, providing the wind and the prop-walk aren't in the same direction!
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As above, a Rival 32, will sometimes do what I want it to do in reverse. But I always have plan B and c for when it won't.

Once she has started to turn then almost impossible to stop her.

Believe me, I have practised til the cows came home.
 
I believe you, Matt. I have only ever met one guy who could reliably steer a long keeler reliably in a marina. Whilst having a chat with the harbour master and having a fag. On the first occasion it was an 8 metre, and several times since then, Kelpie, a 57ft gaffer. He too says it’s just practice. He had a job at a marina age 14, so started quite young. That’s over 40 years of practice, now it’s totally nonchalant, definitely not put on for my benefit.
 
Almost no long keeler steers well in reverse. Many boats particularly but not only motor-sailers have dreadful deadwood and stern profile.

Ideally to go astern smoothly the rear of the boat by the prop should be about as pointed as the front with no deadwood more than about 2cm wide, and neither deadwood nor rudder less than about 6cm from the prop tips. Laminar Flow did a whole posting about the needed flow improvements which I copied for about £250.

However without knowing more about the OP boat and profile, I cant tell if this is the situation here
 
Usual mixed bag of responses including insights. Thanks to all. Like most here I’m experienced, practiced and learning. First boat was long keeled which was small enough to push around. Using prop-walk I got my Ocean 60 in and out of all sorts of tight spots. Owned other boats in between and have eaten a fair share of humble pie.

Early days with current boat which I would rather not name but she has qualities: Sail area / displacement ratio of over 22, a moderate blue water comfort ratio, capsize formula below 2. She sails and looks great.

I bet Mr T is right and a bow thruster would solve much but I’ve never used one. In process of fitting a hydrovane. Never used one of those either. It will be offset and maybe (big dollop of wishful thinking) will help with steerage in reverse. Perhaps not and anyway that not the reason for fitting it.

Got a reply from Flexofold which amounted to; don’t know because it’s so complicated. Might try a fix prop in the future they are not so expensive and can swap back. They do impact sail performance. but from my experience they are as good in reverse as forward.

Thanks again.
 
Mike Bryon said:
Usual mixed bag of responses including insights. Thanks to all. Like most here I’m experienced, practiced and learning. First boat was long keeled which was small enough to push around. Using prop-walk I got my Ocean 60 in and out of all sorts of tight spots. Owned other boats in between and have eaten a fair share of humble pie.

Early days with current boat which I would rather not name but she has qualities: Sail area / displacement ratio of over 22, a moderate blue water comfort ratio, capsize formula below 2. She sails and looks great.

I bet Mr T is right and a bow thruster would solve much but I’ve never used one. In process of fitting a hydrovane. Never used one of those either. It will be offset and maybe (big dollop of wishful thinking) will help with steerage in reverse. Perhaps not and anyway that not the reason for fitting it.

Got a reply from Flexofold which amounted to; don’t know because it’s so complicated. Might try a fix prop in the future they are not so expensive and can swap back. They do impact sail performance. but from my experience they are as good in reverse as forward.

Thanks again.
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What type of Flexofold do you have - 2 or 3 blade. We have the 3 blade and works very well in reverse (and forward) - with some slight prop walk.
Personally I wouldn’t dream of replacing our Flexofold with a fixed prop, as slow down when sailing.
But nobody ever regrets fitting a bow thruster in a 40 footer.

(Separately autopilots so good nowadays I personally wouldn’t bother with a hydrovane - if doing long distance would add hydro-generator instead, as then have the much better steering of modern autopilot with no power concerns)
 
Mike Bryon said:
Usual mixed bag of responses including insights. Thanks to all. Like most here I’m experienced, practiced and learning. First boat was long keeled which was small enough to push around. Using prop-walk I got my Ocean 60 in and out of all sorts of tight spots. Owned other boats in between and have eaten a fair share of humble pie.

Early days with current boat which I would rather not name but she has qualities: Sail area / displacement ratio of over 22, a moderate blue water comfort ratio, capsize formula below 2. She sails and looks great.

I bet Mr T is right and a bow thruster would solve much but I’ve never used one. In process of fitting a hydrovane. Never used one of those either. It will be offset and maybe (big dollop of wishful thinking) will help with steerage in reverse. Perhaps not and anyway that not the reason for fitting it.

Got a reply from Flexofold which amounted to; don’t know because it’s so complicated. Might try a fix prop in the future they are not so expensive and can swap back. They do impact sail performance. but from my experience they are as good in reverse as forward.

Thanks again.
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Have a look at the fixed prop blades. You’ll find they are strongly profiled for performance in the forward direction. Ours was. We have outboard power, therefore fixed is the only option. We switched to a high blade area zero camber prop, with which we can stop the boat quickly enough to upend the washing up. Drag isn’t a factor. For you, your boat plainly has a decent dollop of performance, stiff with plenty of sail. A crying shame to interfere with that, for minimal if any gain in performance astern.
 
Maybe have a think about a Gori prop, had a boat with a 3 blade folding Gori prop for a while, the blades kind of flip round from ahead to astern, meaning when you're in astern, the prop is just as efficient as when going ahead, with only a marginal increase in folded sailing drag compared to a conventional folding propeller. You have to be a bit gentle with it when changing gears, as you want to give the prop a little time to reconfigure from ahead to astern, but it worked like a charm. It also has a neat overdrive mode for efficient motor sailing. Not the cheapest, buy probably the best folding propeller in the world.
 
My first question would be 'how far is it from prop to rudder?'
I've seen some where it is a few days' camel ride.
The greater the distance the harder life becomes.
Fine pitch = lack of transverse thrust = life becomes just a little harder still.

I'm currently having to get my head around a change from left handed (volvo) to right handed (beta) prop but lets consider a right handed prop.
The norm with a right handed prop is to turn 'short round to starboard' to take advantage of the prop walk when you go astern.
If you want to swing through 180º to back into your berth simply 'hard a starboard' and once the swing is started 'midships - full astern'.
The prop walk should continue the starboard turn.
Takes a bit to sort the timing but the theory is that by the time the swing stops you are tracking astern in the required direction. If not then 'hard a starboard' and a quick kick in the guts ahead. She should start swinging again before she stops moving astern. And away you go again.
Keep her moving and use those ahead kicks as required.

Remember ' a stopped ship is a drifting ship' - 'make speed your friend' - and last but not least 'never approach anything at a speed greater than you would want to hit it at'. Bit tricky reconciling the last two but do your best.
 
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