Unlocking the secrets of ferry gliding
It is one of the most satisfying manoeuvres a helm can execute yet its power isn’t always fully realised. Rachel Andrews, RYA Chief Instructor, Motor Cruising and Power, unlocks the secrets of ferry gliding.
“Ferry gliding is a true combination of many practical skills and demonstrates a really good understanding of the prevailing conditions.”
Rachel Andrews knows just how rewarding being able to ferry glide is.
“When you watch someone driving a 50-60m boat with 500-600 people on board and they can berth the boat perfectly in a tight 62m space without the passengers even noticing the boat has stopped alongside, that demonstrates a very high skill level.
“You don’t want 500 full wine glasses tumbling over your guests as the boat bumps against the pier or pontoon! Ferry gliding really is one of the most satisfying skills you can master as a driver and shows that you are a very good powerboater.”
Most simply, ferry gliding is moving a boat sideways, and can be put to great effect to come alongside pontoons, piers or other boats in a slow, controlled manner.
As its name suggests, the term ‘ferry gliding’ originated from the ferries that go from one side of a river to another to the same point, whether the tide is coming in or out, without drifting or being on chains.
Yet the manoeuvre is not for the exclusive use of ferries or large passenger carrying cruisers. It is exceptionally useful when there is only a confined space to moor in as involves no forward or backwards movement so little chance of high impact collision.
At the time of year where space in marinas or on pontoons is at a premium, there are huge advantages to being able to manoeuvre your boat into a tight berth you may never have considered possible, just through applying your knowledge in a different way.
Ferry gliding uses steering, the power of the engine, tide and the wind in combination to make the boat slide sideways. It involves angling the craft so that the wind/stream creates a sideways force on the vessel.
For this explanation of the principles of ferry gliding, assume the boat is pointing forwards into the tide with the current pushing down the river and no wind. If you put the boat into neutral it will go backwards.
Ferry gliding can be done in reverse too, running with the tide, with stern to stream. Experienced powerboaters can instinctively visualise what is happening with the prop under the water, so once you have acquired the skills and understanding to ferry glide bow to tide, you can reverse all the principles for the opposite effect.
The key to a good ferry glide is the slower you can go, the more control you have.
You can allow the boat to go a bit faster by letting the bow come across further – the bigger the angle across the tide, the more influence the tide will have on the boat and the more power will be required to counteract the force of the tide. The danger of trying to go too fast, however, is the nearer you get to the pontoon the effect of tide may become slower, so there is less effect on the bow. This could result in the boat being propelled forward faster than you would want and a possible bump.
When a very good practitioner executes a ferry glide there will be no obvious change in direction, no jerky movements or deviations, just a gentle glide sideways.
Any obstruction in the flow can cause tidal variations and deviations.
Picture the scenario outlined above, but now imagine a bridge just forward ahead of you. The bridge abutments present an obstruction in the stream, and as the water moves past these it will accelerate and slow-down in different places causing disruption to the direction and speed of the current. You cannot always see this.
But even if you do not have any local knowledge, and do not know what is going to happen, you do know that something will happen. The best advice is always to take it slowly so that you have time to react.
Another benefit of ferry gliding in to a pontoon is it can minimise the impact of hitting any underwater obstructions. The standard way to berth a boat is to drive it into the tide with forward momentum, which presents the possibility of puncturing the collar of a RIB or damaging the hull if something unforeseen is submerged. But because with ferry gliding you have already ‘stopped’ and are just drifting gently sideways the danger from potentially hazardous underwater obstructions is reduced.
Whatever the tidal or wind strength or direction, balance is always key. Either the tide or wind will always have more influence than the other, but the combined effect of both with lead to one effect.
With a strong crosswind blowing off the pontoon, as you turn the bow into the wind, the wind will be pushing it back away. You will have to use a lot more power to get the boat across the stream to counteract the force of the wind. But be prepared for the wind to drop going into the shelter of the pontoon, and that the tide may start to have more effect than the wind.
When the wind is blowing on to the pontoon, pushing the boat towards it, any steering towards the pontoon can cause the boat to ‘skate’ in a less controlled manner towards it. Keep the wheel turned to the left, as the wind blows you right to keep the boat parallel to the pontoon, and balance the power accordingly.
Again it is about utilising the skipper’s understanding and knowledge of the wind, tide and handling characteristics of that particular boat.
Sometimes a sudden strong gust or an unexpected acceleration of tide can cause you to need to abandon the manoeuvre.
This is why having an escape plan, and having thought about what you would do if the unexpected occurs, before you start your ferry glide is so important.
The natural reaction in a ‘panic’ situation is often to drive the boat quickly to try to avoid collision, but that is probably the worst thing you could do in this situation. A slow moving boat is always likely to cause and receive less damage.
Even in the worst case scenario and a collision, whether with the pontoon or another vessel, is unavoidable, a slow impact is the best outcome in a bad situation.
Having a transit in the background is a brilliant way for a skipper to judge their position in relation to the pontoon, and if they are moving forwards or backwards.
A transit is usually used in navigation dead straight ahead or behind you, but in ferry gliding it must be on your beam.
Pick an object in the distance and a point on the pontoon and line them up – they must both be fixed points and relevant to the space you are trying to get in to. All the time you have those points lined up you are ‘stationary’ in the water – you might be moving sideways, but you are not moving backwards or forwards.
If you have not got enough power as you get nearer the bank or pontoon, and the tide and/or wind starts to have an effect, the transit will open up.
The bigger the distance between the transits that you choose, the better chance you have of keeping your position. If the transit gap is only small, a minor adjustment in steering will make a big difference to you gauging your position.
Using a transit is a great way of maintaining position.
The skills and knowledge required for ferry gliding could are taught as early as the RYA Powerboat Level 2 course - depending on location and conditions on the day - as a means of coming alongside, or a method of approach in a tidal stream or current.
As Rachel concludes: “Once you have this knowledge then it just becomes about applying your understanding of tide, wind, trim of the boat and, if applicable, sea state, to balance the boat and maintain position.
“I don’t think people always realise the power of good ferry gliding, but I hope more skippers start to appreciate it is not just an advanced technique used by large commercial operators but something that can be employed on a day-to-day basis and really adds another string to your powerboating bow.”