Can trim-tabs help steer when going astern?

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mainsail

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You've got a single engined boat with a single-prop outdrive but no bow-thruster.

You have to reverse into a tight marina berth with a pontoon your port side and a £2m classic J class yacht on your starboard side.

The wind is blowing onto your port bow pushing your boat to starboard and towards the immaculate enamel and varnish of the classic yacht.

Question: How can you keep your boat straight - and stop your bow being blown away from the pontoon and towards the valuable yacht?

Is the answer to go astern with plenty of power AND put the starboard trim tab all the way down? The theory is that, when going astern, the starboard trim tab will act like a brake on the starboard side of the transom and tend to lever the bow to port - counteracting the wind and, hopefully, preventing a collision with the classic yacht.

I'd just like other thread-members to endorse this idea before I actually pluck up enough courage to try it.
 
Trim tabs as a brake!

Going astern with plenty of power is a diaster waiting to happen in this close environment. The trim tab will not act as a brake, in fact it may well suffer damage. Best bet is to fender everything to protect in the event of a SLOW touch as opposed to a crunch collision impact and plenty of slow deliberate movements prehaps using more of neutral than gear. Hope this does not sound obvious but i have had similar frustrating berthing difficulties in the past and learned the hard way!!!!
 
Get someone to hop off with a port stern line, when the bow gets too far to stb, she puts a turn around a cleat on the finger and you engage forward, with the helm dead ahead. The line will go tight, the whole boat will move towards the finger and straighten out, as she comes along side the finger engage reverse again, with crew member constantly taking the slack from the line. Repeat as many times as needed.
 
mainsail said:
You've got a single engined boat with a single-prop outdrive but no bow-thruster.

You have to reverse into a tight marina berth with a pontoon your port side and a £2m classic J class yacht on your starboard side.

The wind is blowing onto your port bow pushing your boat to starboard and towards the immaculate enamel and varnish of the classic yacht.

Question: How can you keep your boat straight - and stop your bow being blown away from the pontoon and towards the valuable yacht?

Is the answer to go astern with plenty of power AND put the starboard trim tab all the way down? The theory is that, when going astern, the starboard trim tab will act like a brake on the starboard side of the transom and tend to lever the bow to port - counteracting the wind and, hopefully, preventing a collision with the classic yacht.

I'd just like other thread-members to endorse this idea before I actually pluck up enough courage to try it.
Click to expand...

it won't work.

I had a single engine baby fly bridge with no bow thruster for a few years. It teaches you how to handle boats.

Remember that your pivot point when going forward is about half way forward. When going astern that pivot point moves aft to a few feet forward of the transom. So going astern in a side wind is the hardest thing you can do as the bows will swing easily and widely.

The only way to do it is to go astern and when the bows start to go, go forward to correct it. two steps back, 1 step forward.

In a stronger wind your scenario just won't be possible. Part of good handling is knowing what is possible and avoiding what isn't!

Fendering either side is very sound advice. There is no shame in planning to end up alongside a boat if properly fendered and dragging yourself over from there. That is not a crash!

You may need to drag her in by hand. You may need to go in forwards and turn her round when the wind drops. It will be different every time planning is the key.

I have 2 engines and a bowthruster now. I came it at about 8pm the day before yesterday and the tide and wind was such that I wasn't sure I could get into my usual berth stern to - I fendered both sides and in the end went in forwards, and turned her round in the morning. I've only had to do that twice since I've been in shamrock - but it isn't always possible to get a boat anywhere - I say again planning is the key.

As for using more power - that is the advanced boat handling class. Power means you'll hit something harder. With lots of experience it can be a tool but if you have to ask, it's wrong.
 
Definitely not recommended, we have had several new boats suffer damage by delivery skippers going astern too quickly with the flaps down, in two cases one of the flaps was completely ripped off, one on a 95ft boat which meant we had to get a diver to block off all the holes where the hydraulic pipes came through the transom to stop water flooding in until we could get it on a slip!
 
mainsail said:
You've got a single engined boat with a single-prop outdrive but no bow-thruster.

You have to reverse into a tight marina berth with a pontoon your port side and a £2m classic J class yacht on your starboard side.

The wind is blowing onto your port bow pushing your boat to starboard and towards the immaculate enamel and varnish of the classic yacht.

Question: How can you keep your boat straight - and stop your bow being blown away from the pontoon and towards the valuable yacht?

Is the answer to go astern with plenty of power AND put the starboard trim tab all the way down? The theory is that, when going astern, the starboard trim tab will act like a brake on the starboard side of the transom and tend to lever the bow to port - counteracting the wind and, hopefully, preventing a collision with the classic yacht.

I'd just like other thread-members to endorse this idea before I actually pluck up enough courage to try it.
Click to expand...

You would really need your wits about you anyway as the tabs are cross wired.

you would have to press the left button down if you wanted the right tab to go down.
 
I've used trim tabs to help steer a few times. When I've been on one engine. I just cannot turn towards the running engine unless I drop that trim tab.

It works ok at a steady 8 knots in open water. The problem is, it does not work at very slow speeds and worse still, if you reduce power, the boat will swing round alarmingly.

So the catch is, if your thinking of backing in at 7/8 knots, it might help, but when you come to stop, the boat will just slur round uncontrollably.

So on ballance, not a good idea. Give it a go some where safe, you might get a different result.
 
trim tabs as brakes

mainsail said:
You've got a single engined boat with a single-prop outdrive but no bow-thruster.

You have to reverse into a tight marina berth with a pontoon your port side and a £2m classic J class yacht on your starboard side.

The wind is blowing onto your port bow pushing your boat to starboard and towards the immaculate enamel and varnish of the classic yacht.

Question: How can you keep your boat straight - and stop your bow being blown away from the pontoon and towards the valuable yacht?

Is the answer to go astern with plenty of power AND put the starboard trim tab all the way down? The theory is that, when going astern, the starboard trim tab will act like a brake on the starboard side of the transom and tend to lever the bow to port - counteracting the wind and, hopefully, preventing a collision with the classic yacht.

I'd just like other thread-members to endorse this idea before I actually pluck up enough courage to try it.
Click to expand...

what about dropping your anchor,then reversing into your berth this should help keep bow from drifting
 
You have to back into the wind ar right angles to the berth then swing the bow against the wind and back into the berth.
It's hard to judge the speed you should go as it depends on the wind speed.

It takes a bit of practice!

The hardest thing is to back into a berth with the wind blowing you in.
 
hlb said:
Why back in at all I just drive in. It makes much more sense.
Click to expand...

It might do for you, but for my boat, on my berth, it makes MUCH more sense to reverse in.

Our moat is about a metre longer than the finger and has a good sized bathing platform, with a transom door. When we reverse in and moor up "stern to", it's walk on, walk off. If we came moored "bow to", we'd have to climb ever the side.
 
Silly designed boats, silly marinas.

So the boat and marina's are now directing folk to moor as they find most efficient.

Boats five ft shorter than before, with a bloody great swim deck. Marinas with five ft shorter pontoons.

Who got hood winked.
 
Have your bows facing down wind reverse and aim about half way along your pontoon as you get closer turn the helm away from your pontoon your bows will go towards your berth and you are ,using the wind as a break. Once you feel the bows moving to winward and your berth straighten up slide in bow line on first.
fender both sides as said before , hope that explains technique , I only use 1 clik of gear 1 boatlength as a guide and 1 metre as thats close enough.
Am sure there are many more way's but this works for me when teaching
.
Tim
 
We all get it pear shaped on occasion, no matter how good we think we are, but if I am going to hit something I would rather it be "just" moving as opposed to 7knots. Generally there is a "helping" hand close by, if not then do the ramming bit and deny all knowledge. lol
 
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