Monday, 28 September 2026

Which Side of the River Has More Wind?

Sometimes crossing the river loses more distance than sailing in the “wrong” direction.

One of the first things we learn when sailing upwind is that the shortest route towards the windward mark is not necessarily a straight one. We tack backwards and forwards, trying to make the best progress towards our destination.

But river sailing adds another complication.

The wind is rarely the same across the whole width of the river.

One bank may have a useful breeze while the other appears almost completely becalmed. Fifty metres farther upstream the situation may reverse. A bend changes the angle of the banks. A line of tall trees suddenly shelters one side. A gap between buildings produces a surprisingly strong puff. A gust arriving from above may touch down in the middle of the river before spreading towards either bank.

This creates one of the most interesting tactical questions in river sailing:

Which side of the river should I sail on?

The frustrating answer is:

It depends — and the answer may change before you get there.

That is precisely what makes river sailing so fascinating.

A River Is Not a Wind Tunnel

When we talk about a forecast wind of, say, 10 knots from the west, it is tempting to imagine 10 knots of wind travelling uniformly across the landscape.

That isn't what happens.

The wind reaching our sails has already interacted with:

trees;
hedges;
buildings;
hills;
riverbanks;
gaps in vegetation;
other boats;
and the surface of the water itself.

On an open stretch of sea, the airflow may have travelled several miles across relatively unobstructed water.

On an inland river, it may have passed through or over a row of mature trees only seconds before reaching your boat.

The result can be a remarkably complicated patchwork of moving air.

One side of the river can therefore have considerably more useful wind than the other.

The Wind Shadow

Trees are particularly important.

Imagine the wind blowing across a line of tall trees before reaching the river.

The trees don't simply stop the wind and create perfectly still air behind them. Instead they disturb the airflow.

Immediately behind the trees there can be an area of reduced wind — a wind shadow.

But the effect extends much farther downwind than the height of the trees themselves.

The airflow can become turbulent, producing alternating patches of stronger and weaker wind.

This is why sailing close to a tree-lined bank can sometimes feel rather strange.

The boat accelerates.

Then stops.

Then heels suddenly.

Then stops again.

The wind direction may change at the same time.

What looks from a distance like a perfectly sensible route along the bank may actually be a succession of holes and turbulent gusts.

The Upwind Bank and the Downwind Bank

Suppose the wind is blowing approximately across the river.

One bank is therefore the windward bank and the other is the leeward bank.

At first sight it might seem obvious that the windward side should have more wind because it receives the breeze first.

Often it does.

But river sailing rarely rewards absolute rules.

If the windward bank has tall trees immediately beside the water, those trees may disturb the airflow before it reaches you.

Meanwhile, wind passing over buildings farther back from the opposite bank might descend towards the water and produce stronger patches elsewhere.

So instead of thinking:

“The windward bank is always better.”

Think:

“What has the wind travelled over before it reaches that part of the river?”

That is a much more useful question.

Look Upwind — But Look Beyond the River

This is one of the habits I increasingly find valuable when sailing on a river.

Don't just look at the water immediately ahead.

Look farther upwind.

Ask yourself:

Where has this air come from?

Perhaps there is:

a field;
a gap between trees;
a road;
a large building;
a valley;
a wooded bank;
or an opening between houses.

A large open field may allow relatively clean airflow towards the river.

A dense wood may produce considerable turbulence.

A gap between trees can occasionally act almost like a gateway through which stronger wind reaches the water.

Learning the geography around the river therefore becomes part of learning to sail it.

Experienced river sailors aren't merely sailing the boat.

They are gradually building a mental map of the wind.

Bends Change Everything

Now add a bend in the river.

Suddenly the relationship between the wind and the banks changes.

A bank that was providing relatively clean airflow may become sheltered.

The apparent wind angle changes relative to the river.

A line of trees that previously had little effect may suddenly lie directly upwind.

This is one reason why river sailing can demand so much concentration.

You may discover an excellent patch of wind and think:

“This is clearly the side to be on.”

Two hundred metres later that conclusion may be completely wrong.

Buildings Can Create Surprising Wind

Buildings add another complication.

Wind flowing around a building can accelerate around corners and through gaps.

It can also separate from the structure and create turbulent regions behind it.

That means a clubhouse, large house, industrial building or group of riverside properties can produce local wind patterns quite different from the general wind direction.

You may find a repeatable puff appearing in approximately the same place.

That isn't necessarily coincidence.

There may be a geographical reason for it.

This is where local knowledge becomes extremely valuable.

Someone who has sailed the same stretch of river for twenty years may know that:

“With a south-westerly, there's usually a useful puff just beyond those trees.”

That knowledge can be worth several boat lengths.

But even local knowledge needs to be treated cautiously.

Wind strength changes.

Wind direction changes.

Trees grow.

Buildings appear.

The atmosphere itself changes.

Yesterday's perfect route isn't automatically today's perfect route.

Pressure — Finding the Darker Water

Sailors often talk about pressure.

In this context we aren't normally talking about atmospheric pressure measured by a barometer.

We mean an area where there is more useful wind.

Learning to see these patches is one of the most useful skills a sailor can develop.

Look across the river.

Does one area of water look darker?

Is there more texture on its surface?

Are small ripples appearing?

Are moored boats beginning to move?

Are flags or burgees suddenly lifting?

Are the leaves on trees moving?

Most importantly:

What are the boats ahead doing?

A boat fifty metres ahead can be an excellent wind detector.

If it suddenly heels and accelerates, something has happened.

A gust may be heading towards you.

If three boats near one bank are moving while three boats on the opposite bank are almost stationary, that is useful information.

The river is showing you where the energy is.

Don't Just Look for More Wind — Look for Better Wind

There is an important distinction here.

The strongest wind isn't necessarily the best wind.

Imagine one side of the river has slightly stronger wind but it is extremely turbulent and frequently headed.

The opposite side has slightly less wind but it is steadier and provides a better angle towards the mark.

Which is better?

Probably the second — depending on the tactical situation.

What matters is not simply boat speed.

What matters is progress towards where you want to go.

That brings us back to velocity made good.

You can think of it simply as:

VMG = boat speed x cos(angle away from the desired direction)

You don't need to calculate it while racing.

The important principle is that speed in the wrong direction isn't necessarily useful speed.

But There Is Another Cost: Crossing the River

Suppose you are sailing up the right-hand side of the river.

You look across and notice slightly more wind on the left.

Should you tack and cross?

Perhaps.

But crossing has a cost.

You must tack.

You may lose speed during the manoeuvre.

You travel sideways across the river.

You may encounter other boats.

And by the time you reach the supposedly better wind, it may have disappeared.

This leads to one of the most important tactical ideas in river sailing:

A better patch of wind is only useful if the gain from reaching it is greater than the cost of getting there.

That is why the shortest-looking tactical decision isn't always the fastest one.

The Temptation to Chase Every Gust

This is particularly noticeable in light winds.

You see darker water twenty metres away.

You tack towards it.

The patch moves.

So you tack again.

Another gust appears somewhere else.

You change direction again.

Before long you have sailed an enormous distance while the apparently less active sailor beside you has simply continued steadily up the river.

And somehow they are ahead.

There is a lesson here.

Don't chase every gust.

Instead ask:

Is this a persistent advantage or merely a temporary patch of wind?

That distinction comes largely from experience.

Sometimes Sailing the “Wrong” Way Is Right

Imagine the windward mark lies slightly towards the left-hand side of the river.

The obvious strategy might be to favour the left.

But suppose the left bank is heavily sheltered by trees.

The right-hand side has clean breeze coming through an open field.

Sailing towards the right may initially appear to take you away from the mark.

Yet if you maintain 4 knots while boats on the left struggle at 2 knots, the apparent detour may produce a substantial advantage.

This is one of those situations where sailing teaches an important tactical principle:

Distance isn't the only thing that matters.

Speed matters.

Wind angle matters.

Current matters.

And what happens next matters.

Current Makes the Decision Even More Interesting

On a river we also have to consider the movement of the water.

Suppose the stronger wind is on one side but the favourable current is on the other.

Now the tactical problem becomes:

Wind versus current.

In light winds, current can dominate.

In stronger winds, the additional boat speed available from better pressure may be more important.

Again, there isn't a universal answer.

That is why good river sailing involves constant observation rather than memorising rules.

Watch the Fleet

One of the simplest experiments you can try during a race or training session requires no equipment whatsoever.

Instead of concentrating only on your own boat, deliberately spend a few seconds looking across the entire river.

Ask:

Who is moving fastest?

Then ask:

Why?

Perhaps they have:

more wind;
a better angle;
favourable current;
cleaner air;
fewer obstructions;
or simply better sail trim.

Over time you begin to recognise patterns.

This is particularly useful when boats ahead split onto different sides of the river.

They have accidentally created an experiment for you.

Watch what happens.

One group may reveal which side currently has the advantage.

Use Champagne as a Wind Detector

Sailing Champagne, our A-Rater, makes this particularly interesting.

A long, powerful boat with a large sail area reacts very visibly to changes in pressure.

A patch of extra wind can produce a noticeable increase in heel and speed.

That means photographs or video taken from another boat can become surprisingly useful afterwards.

Look at the water around Champagne.

Look at the heel angle.

Look at the sail shape.

Look at nearby boats.

Then compare those observations with what happened next.

Video can turn an instinctive sailing experience into something that can actually be studied.

It is one reason I increasingly think that filming sailing isn't simply about producing attractive pictures.

It can become a coaching tool.

A Simple Training Exercise

Next time you are sailing on a river, try this.

Choose a reasonably open section and, before making a tactical decision, identify three zones:

Left — Middle — Right

For each zone ask:

How much wind can I see?
What direction does it appear to be coming from?
What lies upwind of it?
What are other boats doing there?
What is the current doing?
How much would it cost me to reach it?

Then make your decision.

A minute later, look again.

Was your prediction correct?

If not, don't regard that as failure.

Ask why it was wrong.

That is how tactical judgement develops.

The Most Important Lesson: Keep Looking

Perhaps the biggest mistake is finding the good side of the river and assuming it will remain the good side.

It won't necessarily.

The wind shifts.

Gusts move.

Clouds alter heating.

Bends change the geography.

Trees shelter different areas.

Buildings redirect airflow.

Other boats interfere with your wind.

The river itself changes direction beneath you.

So the question isn't really:

“Which side of the river has more wind?”

It is:

“Which side of the river has the best wind for what I need to do next?”

And then, perhaps thirty seconds later:

“Is that still true?”

That is a very different way of thinking.

River Sailing Is a Moving Puzzle

This is one reason I find river sailing so interesting.

On large open water, tactics can involve major wind shifts and large-scale weather patterns.

On a narrow, tree-lined river, the puzzle can happen within tens of metres.

A tree.

A building.

A bend.

A patch of darker water.

A boat ahead suddenly heeling.

Each provides another piece of information.

The sailor who learns to notice these clues starts seeing the river differently.

You stop thinking of the wind as something that simply blows across the whole racecourse.

Instead, you begin to see paths of usable energy moving across the water.

And occasionally that leads to a wonderfully counter-intuitive decision.

The mark may be on the left.

The shortest route may be on the left.

Everyone else may be heading left.

But the breeze is on the right.

Sometimes sailing farther is the fastest way to get there.

And sometimes crossing the river in search of something slightly better simply costs more than staying where you are.

The skill isn't knowing which side of the river has more wind.

The skill is learning to recognise when it is worth going there.

Return to pmrsailing.uk https://pmrsailing.uk/sailing-lessons/How-to-sail-better.html

The Crew Isn't Just Extra Weight

A good crew can make the helm look much better than they really are.

Watch a two-person sailing boat from the bank and it is easy to assume that one person is doing most of the important work.

The helm has the tiller.

The helm decides where the boat goes.

The helm calls the tack.

The helm appears to be sailing the boat.

Meanwhile, the crew seems to be moving from side to side, pulling a rope occasionally and, perhaps, providing some useful ballast.

That is a very misleading picture.

As you become a better sailor, you begin to realise that a good crew is not a passenger and certainly isn't simply movable ballast.

The crew can be trimming one of the most important sails on the boat, controlling balance, watching approaching gusts, looking for wind on the water, checking other boats, spotting tactical opportunities and feeding the helm information that the helm simply cannot see.

In a well-sailed boat, helm and crew are not two independent sailors.

They become a team.

And when that partnership really works, it can sometimes be difficult to tell which sailor is making the boat go fast.

Why the Crew Matters More as You Improve

When we first learn to sail, responsibilities tend to be deliberately separated.

The helm steers.

The crew handles the jib.

That is a perfectly sensible way to begin because there is already enough happening without making things more complicated.

But eventually those simple roles need to develop.

Instead of thinking:

Helm = steering

and

Crew = jib

start thinking:

Helm + crew = sailing the entire boat.

That change in attitude can make an enormous difference.

1. The Crew Helps Control the Balance of the Boat

One of the five essentials of sailing is balance, and the crew can have a huge influence over it.

On a light-wind day, that might mean moving inboard or even sitting on the leeward side.

As the wind increases, the crew moves towards the windward side.

In stronger conditions, both sailors may need to work hard to keep the boat flat.

Why?

Because a sailing boat generally performs best when it is sailed at an appropriate angle of heel rather than simply being allowed to lean farther and farther whenever a gust arrives.

Excessive heel can increase weather helm and drag. The rudder may then need a larger angle to keep the boat travelling in the intended direction.

That rudder angle isn't free.

The rudder is producing force, and producing that force also creates drag.

So when the crew moves their weight to help keep the boat balanced, they aren't merely making things more comfortable.

They may actually be reducing drag and helping the boat sail faster.

2. Move Before the Boat Heels

There is an important distinction between an inexperienced crew and an experienced one.

The inexperienced crew reacts.

The experienced crew anticipates.

Imagine that you are sailing upwind and a stronger gust is approaching.

The inexperienced sequence might be:

Gust arrives -> boat heels -> helm reacts -> crew moves.

The better sequence is:

Crew sees gust -> crew warns helm -> crew prepares -> gust arrives -> both respond together.

That difference might only amount to a second or two.

But those seconds matter.

Instead of the boat suddenly heeling, rounding towards the wind and losing speed, it can remain comparatively flat and accelerate.

This connects directly with another important skill I have discussed in this series:

learning to read the water.

The crew is often in an excellent position to do this.

3. The Crew Can Become the Boat's Wind Spotter

The helm has a problem.

They need to look where the boat is going.

There may be other boats nearby. There may be a riverbank approaching. They may be concentrating on tell-tales, steering angle, the next mark and maintaining boat speed.

The crew has another pair of eyes.

Use them.

Look upwind.

Look for darker patches on the water.

Look at what is happening to boats ahead.

Are they suddenly heeling?

Has a boat 50 metres ahead slowed dramatically?

Has another boat suddenly lifted?

Is there a patch of apparently stronger wind approaching from one side of the river?

On inland waters this becomes particularly valuable because the wind can be extraordinarily variable.

Trees, buildings, banks and bends can disturb the airflow.

The wind experienced by one boat may be quite different from that experienced by another boat only a short distance away.

The crew can therefore become something rather like the boat's early-warning system.

Useful calls might be:

"More pressure coming in ten seconds."

"Big gust coming from the left."

"Looks lighter ahead."

"Boats ahead are lifting."

"Pressure looks better on our side."

Those are far more useful than waiting until the boat is already heeling dramatically and announcing:

"Gust!"

4. Jib Trim Is Much More Than Pulling the Sheet In

The crew's most obvious control is usually the jib sheet.

But simply pulling it in until it looks approximately correct is only the beginning.

The jib needs continuous attention.

Watch the tell-tales.

If the windward tell-tale lifts first, the boat may be too close to the wind or the sail may need adjustment.

If the leeward tell-tale behaves badly, the jib may be over-sheeted.

Watch the shape of the sail.

Watch the leech.

Watch how the boat accelerates after a tack.

And remember that the correct sheet position isn't necessarily permanent.

The wind changes.

The boat changes course slightly.

A gust arrives.

A lull arrives.

The helm bears away a few degrees.

Suddenly the jib setting that was correct five seconds ago may no longer be ideal.

This connects directly with another principle of performance sailing:

small adjustments often beat occasional large ones.

A good crew may be constantly making tiny sheet adjustments.

A centimetre here.

Two centimetres there.

Ease slightly in the gust.

Trim again as the boat settles.

From the riverbank, almost nothing appears to be happening.

Inside the boat, however, there is constant optimisation.

5. The Jib and Mainsail Need to Work Together

There is another reason why the crew's job matters.

The jib and mainsail aren't really independent sails.

Airflow around one affects airflow around the other.

This means the helm and crew should not independently decide:

"My sail looks right."

The question should be:

Are our sails working together?

If the crew dramatically changes the jib trim, it may alter the feel of the entire boat.

Similarly, if the helm changes the mainsheet or changes course, the crew may need to alter the jib.

This is why communication matters.

The two sailors should gradually begin to anticipate each other.

6. Communication Makes a Fast Boat

Poor communication often sounds like this:

"Tack!"

"When?"

"NOW!"

"What?"

"TACK!"

By then, the opportunity has probably gone.

Better communication gives everyone time to prepare.

"Thinking about a tack."

"Clear behind?"

"Yes."

"Ready about."

"Ready."

"Lee-oh."

The exact words aren't particularly important.

Consistency is.

Both sailors need to know what the calls mean.

The same applies when approaching a gust.

"Pressure in five."

"Got it."

The crew moves.

The helm prepares to adjust the mainsheet or heading.

The gust arrives.

The boat accelerates rather than falling over.

It begins to feel less like two people reacting independently and more like one coordinated system.

7. The Crew Can See Things the Helm Cannot

This becomes particularly important when racing.

The helm cannot continuously look everywhere.

The crew can provide information about:

boats behind;
boats approaching on another tack;
overlaps;
the position of marks;
stronger wind elsewhere;
approaching gusts;
potential obstructions;
what competitors are doing;
space near the bank;
possible tactical opportunities.

The important point, however, is not simply to produce an endless commentary.

Information should be useful, timely and concise.

Imagine the helm is concentrating on sailing through a difficult patch of disturbed wind.

The crew saying:

"There's a red boat over there."

isn't particularly useful.

Compare that with:

"Starboard boat approaching — about 20 seconds."

That tells the helm something they can act upon.

8. Information Is Different From Decision-Making

There is an interesting stage in developing a helm-and-crew partnership.

Initially the helm may make virtually every decision.

Eventually the crew begins supplying information.

Later still, tactical decisions can become genuinely collaborative.

For example:

Crew: "More pressure on the left."

Helm: "How far?"

Crew: "Maybe 30 metres. The two boats there are moving faster."

Helm: "We'll tack towards it after this gust."

That is very different from the crew simply waiting for an instruction to pull a sheet.

The crew is now actively contributing to the boat's strategy.

9. A Good Crew Watches Other Boats

Other boats are extraordinarily useful sailing instruments.

Suppose three boats ahead suddenly heel.

You have just received a gust warning.

Suppose boats on the opposite side of the river appear to be moving while the boats around you are almost stationary.

That tells you something about the distribution of the wind.

Suppose a boat ahead suddenly changes heading without apparently moving its tiller dramatically.

It may have encountered a wind shift.

A good crew learns to watch these clues.

Sometimes the fastest way to discover what the wind is doing isn't to stare at your own burgee.

It is to watch what the wind is doing to somebody else's boat.

10. The Crew Has an Important Role During a Tack

A tack isn't simply:

helm pushes tiller -> crew swaps sides.

Done badly, a tack can destroy a surprising amount of speed.

The jib is released too early.

The boat slows.

The new sheet is pulled in too aggressively.

The sail stalls.

The crew crosses the boat too late.

The boat heels.

The helm uses excessive rudder.

More speed disappears.

A well-coordinated tack is very different.

The helm starts the turn smoothly.

The crew releases the old sheet at the appropriate moment.

The jib crosses.

The crew moves across the boat while keeping it balanced.

The new sheet is brought in progressively.

The helm straightens the rudder.

Both sailors help the boat accelerate.

The objective isn't simply to get onto the other tack.

The objective is to emerge from the tack still moving quickly.

11. Sometimes the Crew Shouldn't Pull the Jib Straight In

This is a subtle but useful performance point.

After a tack, there can be a temptation to pull the jib immediately into its final close-hauled position.

That may not always produce the fastest acceleration.

The boat has just slowed during the manoeuvre.

It needs to accelerate again.

Depending on the boat and conditions, allowing the jib to breathe slightly before progressively trimming to the final position can help the boat build speed.

It is rather like changing gear.

First get the boat moving.

Then optimise the sail for the new course.

The crew needs to feel this rather than simply following a rule saying:

"After a tack, pull the jib to this mark."

12. Crew Weight Is Dynamic

Where the crew sits isn't something that should be decided at the beginning of the race and forgotten.

Forward or aft?

Windward or leeward?

Inboard or outboard?

The answer depends on the boat, wind strength and point of sail.

In very light conditions, movement itself can be disruptive.

The crew may therefore need to move gently and deliberately.

As the wind increases, rapid movement becomes more important.

The key idea is that body weight is another control.

We normally think of:

tiller;
mainsheet;
jib sheet;
kicker;
centreboard.

But sailors themselves are part of the control system.

Where perhaps 60–90 kg of crew weight is positioned can have a substantial effect on a small sailing boat.

13. Don't Fight Each Other

One of the most interesting problems occurs when helm and crew both try to solve the same problem differently.

A gust arrives.

The helm eases the mainsail.

At exactly the same moment, the crew changes position dramatically.

The helm then bears away.

The crew trims the jib.

Suddenly everyone is correcting everyone else's correction.

The boat begins weaving through the water.

This is why experienced teams can sometimes appear remarkably calm.

It isn't necessarily because less is happening.

It is because their actions complement rather than contradict each other.

14. Sailing Champagne Has Reinforced This for Me

Sailing an A-Rater such as Champagne makes the idea that a crew is simply "extra weight" particularly difficult to defend.

On a long, powerful river racing boat, coordination matters enormously.

There is a lot happening.

Sail trim matters.

Weight placement matters.

Wind shifts matter.

River position matters.

Other boats matter.

And the wind on the Thames certainly doesn't have the courtesy to remain constant while everyone sorts themselves out.

One of the things I increasingly notice when sailing is just how much useful information exists outside the boat.

You can see wind approaching across the water.

You can see what it is doing to another boat.

You can see a boat ahead being lifted or headed.

You can see one side of the river beginning to develop more pressure.

But the person steering cannot spend the whole time looking around.

That is where an observant crew becomes immensely valuable.

The crew isn't merely responding to what has happened.

They are helping predict what is about to happen.

15. The Same Applies When I Crew

There is also an interesting change of perspective when you swap roles.

When crewing rather than helming, you begin to notice opportunities to make the helm's job easier.

Good jib trim means the helm doesn't have to compensate for poor sail shape.

Good balance means less rudder correction.

An early gust warning means the helm can prepare.

Clear information about another boat means the helm doesn't need to keep turning around.

That leads to a useful principle:

A good crew removes problems before the helm has to solve them.

And perhaps that explains why a really good crew can make a helm look so accomplished.

16. Try This Exercise: Sail With a Talking Crew

On your next sail, try a simple exercise.

For ten minutes, ask the crew to concentrate on information rather than tactics.

Call:

"Gust approaching."

"Lull ahead."

"Boat behind."

"Starboard boat approaching."

"More pressure towards the bank."

"Windward tell-tale lifting."

Then discuss which calls were useful.

The object isn't to create constant noise.

It is to discover which information helps the person steering sail the boat better.

Then reverse the roles.

It is surprising how quickly both sailors begin understanding what the other person actually needs.

17. Try a Second Exercise: The Silent Boat

Then try almost the opposite.

Sail for several minutes with minimal conversation.

The challenge is for each sailor to anticipate what the other will do.

When a gust approaches, can both sailors respond together?

During a tack, can the crew cross at exactly the right moment?

Can the jib be released and trimmed without instructions?

Can the helm feel from the boat's behaviour what the crew has done?

This starts developing something very valuable:

team awareness.

Eventually, good sailing becomes less about issuing instructions and more about anticipating each other.

18. The Crew Can Make the Helm Faster

There is a final point which is easy to overlook.

The helm has limited mental capacity.

If the helm is simultaneously trying to:

steer accurately,

watch the mainsail,

judge the next tack,

look for gusts,

monitor competitors,

find the mark,

watch the riverbank,

remember the course,

and work out whether that approaching boat has right of way,

something will eventually receive less attention than it deserves.

A good crew removes some of that workload.

The helm can then concentrate more effectively on one particularly important task:

making the boat travel quickly in the right direction.

That is why good teamwork doesn't merely make sailing easier.

It can make sailing faster.

Stop Thinking of the Crew as a Passenger

When people begin sailing, it is understandable that the helm appears to be in charge.

After all, they have the tiller.

But performance sailing gradually reveals a much more interesting relationship.

The helm may determine where the boat points, but the crew can influence how efficiently it gets there.

The crew controls sail shape.

The crew controls balance.

The crew sees approaching wind.

The crew watches competitors.

The crew supplies tactical information.

The crew helps the boat through manoeuvres.

And, perhaps most importantly, the crew allows the helm to concentrate.

The best helm-and-crew partnerships eventually stop looking like two sailors carrying out separate jobs.

They look like one sailing system.

So the next time somebody describes the crew as "extra weight", perhaps put them in the boat with a really good crew.

Then send them out again without one.

They may suddenly discover just how much work that "extra weight" was doing.

A good helm can sail a boat well.

A good helm and crew can make each other better.

And sometimes a particularly good crew can make the helm look much better than they really are.

Return to pmrsailing.uk https://pmrsailing.uk/sailing-lessons/How-to-sail-better.html

Saturday, 26 September 2026

Why River Sailing Is Different From Sailing on Open Water

On a river, the wind you see at the masthead may not be the wind reaching your sails.

Sailing is sailing. The basic principles do not suddenly change because you leave the sea and enter a river.

The sails still generate aerodynamic force. The keel or centreboard still resists sideways movement. The rudder still steers the boat. You still tack through the wind and gybe with it behind you.

But put the same boat on a relatively narrow, tree-lined river and sailing can become a remarkably different game.

Trees interfere with the wind. Banks create shelter. Buildings generate turbulence. Bends change the apparent orientation of the course. The current may help you in one direction and hinder you in another. The available water limits your tactical choices.

And sometimes you can look at the burgee at the top of the mast, see it streaming confidently in one direction, while the sails appear to be experiencing something quite different.

Welcome to river sailing.

For some sailors these complications sound frustrating.

I think they are part of what makes river sailing so fascinating.

The Wind Doesn't Simply Blow Across a River

When we first learn to sail, diagrams generally show beautifully behaved wind.

There is an arrow labelled WIND.

The arrow points in one direction.

We then learn where to position the sails relative to it.

Real wind is considerably less cooperative, particularly on an inland river.

Imagine a breeze approaching a river surrounded by mature trees.

The air cannot simply travel through the trees unaffected. It has to flow around and over them. Individual trees, hedges, buildings and changes in terrain disturb that flow.

The result can be a complicated mixture of:

relatively clean wind;
sheltered areas;
gusts;
turbulence;
wind shear;
eddies;
headers;
lifts;
and occasionally patches that seem to contain almost no useful wind whatsoever.

Two boats separated by surprisingly little distance can therefore experience different conditions.

That makes observation enormously important.

The Masthead Can Tell Only Part of the Story

This produces one of the fascinating features of river sailing.

Look upwards and your burgee may indicate one wind direction.

Look at the jib tell-tales and they may suggest something slightly different.

Look at the water fifty metres ahead and yet another story may be developing.

That isn't necessarily because one of your indicators is wrong.

The wind can genuinely be different at different heights.

Close to the surface, friction with trees, banks and the ground slows and disturbs the airflow. Higher up, the wind may be stronger and less affected by some of these obstructions.

A tall mast can therefore extend through several slightly different layers of moving air.

On an open stretch of water the difference may be relatively small.

Beside a wooded riverbank it can become much more noticeable.

This is why I regard the burgee as one instrument rather than the instrument.

I also want to see the sails, tell-tales, water, nearby boats and trees.

Together they tell me much more.

Trees Create Both Shelter and Turbulence

Trees are particularly interesting.

Sail close to a heavily wooded bank with the wind coming from behind those trees and you may enter their wind shadow.

The wind can weaken dramatically.

But the effect isn't simply an area of reduced wind immediately behind the trees.

Air flowing across an obstruction can become turbulent downstream.

Think about water flowing past a rock in a stream.

Behind the rock there isn't simply stationary water. There are swirls, eddies and constantly changing flow.

Air can behave similarly.

A line of trees can therefore create a region in which the wind continually changes strength and direction.

One moment the boat is powered.

Seconds later the sails soften.

Then a gust arrives from a slightly unexpected direction.

This is why river sailing rewards sailors who continually adjust rather than set the sails once and leave them alone.

Buildings Can Be Even More Interesting

Buildings can produce surprisingly dramatic effects.

Air flowing around a clubhouse, house, boathouse or industrial building can accelerate around corners, separate from surfaces and produce turbulent wakes.

You can occasionally sail towards what appears to be a sheltered area and suddenly receive a strong gust.

The opposite can happen just as quickly.

This becomes particularly interesting when racing.

A sailor who has sailed the same river for years may know that a particular group of trees usually produces a lull, or that a certain gap between buildings sometimes funnels the wind.

That local knowledge can be extremely valuable.

But it should never replace observation.

Today's wind direction may be only ten degrees different from yesterday's.

That can completely alter which obstacles matter.

River Bends Change the Game

On open water, the relationship between the course and the wind can remain relatively straightforward.

A river bends.

Suppose you are sailing upstream towards a mark.

For one section, the river may run almost directly into the wind.

Round the next bend, the same wind might suddenly put you on a reach.

Another bend might require another tack.

The wind hasn't necessarily changed.

The orientation of the sailing area has.

That means river sailors continually reassess their situation.

Instead of asking only:

"Where is the wind coming from?"

we also need to ask:

"What does that wind mean for the next section of river?"

This makes bends tactically fascinating.

Then There Is the Current

Wind moves the boat through the water.

The river moves the water across the ground.

Those are different things.

Suppose your boat is sailing through the water at 4 knots while the river current is flowing downstream at 1 knot.

Very approximately, if you are sailing directly upstream your speed over the ground could be:

4 - 1 = 3 knots

Sail directly downstream and it could become:

4 + 1 = 5 knots

Real sailing is rarely quite that simple because the boat and current may be travelling at different angles, but the principle matters.

And the current isn't necessarily identical across the whole river.

It may be stronger in the deeper central channel and weaker near the bank.

Suddenly the shortest route may not be the fastest route.

The Bank Can Become Part of Your Tactics

Suppose you are racing upstream against the current.

You might choose to sail closer to the bank where the current is weaker.

But now another problem appears.

The bank might also shelter you from the wind.

So which is better?

Stronger wind and stronger adverse current?

Or weaker current and weaker wind?

There isn't a universal answer.

That is precisely what makes the decision interesting.

The correct choice may change within minutes.

River sailing becomes a continuous optimisation problem.

You are balancing wind strength, wind direction, current, distance, traffic and available space.

You Cannot Always Tack When You Want To

On open water, a tactical discussion might conclude:

"We should tack now."

On a river the answer may be:

"We should—but we can't."

There might be another boat alongside you.

The bank may be approaching.

A moored boat may restrict the available water.

A navigation channel may need to remain clear.

A bend may make the manoeuvre undesirable.

Or the next tack may leave you trapped beneath trees with almost no wind.

This is one reason why deciding when to tack becomes such an important river-sailing skill.

The theoretical best tack is not necessarily the practical one.

Sometimes you have to think two or three manoeuvres ahead.

The Riverbank Is Not Always Your Friend

There is a great temptation to use every centimetre of available water when racing.

Sometimes that is exactly what you should do.

But there is a danger.

Sail too close to a bank and several things can happen simultaneously.

The wind may become weaker.

The wind may become more turbulent.

Your tactical options disappear.

And if something unexpected happens, there may be very little room to recover.

That last point matters.

A few metres of extra water can sometimes be worth more than gaining another metre towards the bank.

Read the Water

This connects directly with one of my favourite sailing lessons:

Stop staring at the sails and start looking outside the boat.

On a river, the water ahead can reveal a great deal.

A darker patch may indicate stronger wind.

A line of ripples may show an approaching gust.

A smooth patch may indicate lighter pressure.

Other boats provide information too.

If a boat fifty metres ahead suddenly heels, something has happened.

If three boats ahead simultaneously slow down, that is useful information.

If boats on one side of the river are moving noticeably faster than boats on the other, ask why.

They are effectively sailing weather stations.

Watch the Trees as Well

Trees aren't merely obstacles to the wind.

They are also indicators of it.

Look at the upper branches.

Are they moving?

Which direction are the leaves being blown?

Is one group of trees moving while another remains still?

This can sometimes reveal an approaching gust before it reaches the water around you.

River sailing encourages you to develop an increasingly large field of attention.

The beginner looks at the sail.

The improving sailor looks at the boat.

The experienced sailor is increasingly looking at the environment in which the boat is about to sail.

Headers and Lifts Become Particularly Important

A river's disturbed wind makes small changes in direction extremely significant.

Imagine sailing close-hauled when the wind shifts.

If it moves towards the bow, you are headed.

If it moves aft, you are lifted.

On open water you might have time to observe a developing wind shift and decide what to do.

On a river the consequences can arrive remarkably quickly.

A lift might allow you to continue towards the next bend without tacking.

A header might suddenly make the opposite tack much more attractive.

But because the river is narrow, you may have only seconds to exploit it.

This is where sailing moves beyond simply knowing the controls.

You begin making decisions.

Sometimes the "Wrong" Side Works

One of the delights of river racing is watching apparently strange decisions succeed.

Someone sails towards what appears to be the wrong bank.

Why?

Perhaps they have spotted stronger pressure.

Perhaps they know the current is weaker there.

Perhaps they expect a lift.

Perhaps the next bend favours that position.

Or perhaps they have simply made a mistake.

You won't know until the situation develops.

That uncertainty makes river racing particularly interesting.

Champagne Makes These Effects Especially Noticeable

Sailing Champagne, our A-Rater, makes me particularly conscious of the river environment.

A longer boat carrying a substantial sail area can respond dramatically to changes in pressure.

A gust arriving can suddenly transform the boat.

Then the wind disappears behind trees and everything changes again.

With several people aboard, the challenge is not merely recognising the change but coordinating the response.

The helm may need to alter course.

The mainsail may need adjusting.

The jib needs trimming.

Crew weight may need moving.

And ideally much of that happens before the boat has lost momentum.

That last point is particularly important.

Momentum Is Precious

In light, disturbed river winds, boat speed is something worth protecting.

If the wind briefly disappears, a boat that already has momentum can continue moving.

A boat that has been over-steered, over-sheeted or allowed to slow may stop.

Once stopped, restarting can be frustratingly difficult.

This is why smooth sailing matters.

Avoid unnecessary rudder movement.

Keep the sails working.

Anticipate changes.

Maintain flow.

Sometimes the best response to a short lull is surprisingly little.

Let the boat carry itself through it.

Local Knowledge Matters — But Observation Matters More

Experienced river sailors often appear to know mysterious secrets.

"Don't go under those trees."

"Stay on this side after the bend."

"There's usually more pressure near that bank."

Years of sailing the same stretch undoubtedly create valuable local knowledge.

But conditions never repeat perfectly.

Wind strength changes.

Wind direction changes.

Water levels change.

Trees grow.

Trees disappear.

Even seasonal foliage changes the airflow.

So I think the real lesson is not simply to memorise where the good wind normally lives.

Learn why it might be there.

Then look for evidence that it is actually there today.

River Sailing Is a Wonderful Classroom

Open-water sailing gives space.

River sailing gives problems.

And problems make us think.

Every few minutes the river asks another question.

Where is the next gust?

Which bank has the better wind?

Where is the current strongest?

Can I make that bend without another tack?

Should I tack now or wait?

Why has that boat suddenly accelerated?

Why have my tell-tales changed when the masthead burgee hasn't?

Can I maintain momentum through this lull?

There may not be a perfect answer.

You make your decision, sail another hundred metres and discover whether you were right.

Then you try again.

Why River Sailing Can Be So Much Fun

It would be easy to describe all this as making river sailing difficult.

I prefer to say it makes river sailing interesting.

A relatively short stretch of water can contain an extraordinary number of tactical and technical challenges.

You are not simply controlling a sailing boat.

You are interpreting a constantly changing environment.

Wind, water, trees, buildings, bends, banks, current and other boats are all providing information.

The more you sail, the more of that information you begin to notice.

And gradually something rather satisfying happens.

You stop merely reacting to what the boat is doing.

You begin anticipating what it is about to do.

That is one of the great steps in becoming a better sailor.

On a river, the wind you see at the masthead may not be the wind reaching your sails.

But once you learn to read the river, that complicated, imperfect and constantly changing wind becomes part of the fun.

And perhaps that is why river sailing can be so addictive.

Every trip along exactly the same stretch of water can present a completely different puzzle.

The river may be narrow, but the amount it can teach you about sailing is enormous.

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Friday, 25 September 2026

When Should You Tack?

Knowing how to tack is beginner sailing. Knowing when to tack changes everything.

One of the first things we learn when sailing is how to tack.

Push the tiller away. Let the bow turn through the wind. Move across the boat. Change sides. Settle onto the new tack and get sailing again.

Eventually the mechanics become almost automatic.

But then comes a much more interesting question:

Why did you tack there?

That is where simply sailing a boat begins to turn into racing a boat.

A perfectly executed tack at the wrong moment can lose far more distance than a slightly untidy tack made for the right reason.

And on inland water, particularly somewhere like the River Thames, deciding when to tack becomes especially fascinating. The wind shifts, the river bends, trees interfere with the airflow, other boats occupy the water you want to use, and the fastest route towards the next mark may change several times within a minute.

So rather than asking:

"Can I tack?"

we need to start asking:

"Should I tack now?"

First, Remember That Every Tack Has a Cost

Tacking is not free.

Before the tack, the boat has useful forward speed.

As you turn towards the wind, the sails temporarily produce less driving force. The boat continues largely because of its momentum.

Then the bow passes through the wind, the sails fill on the opposite side and the boat accelerates again.

During that process you lose some speed and therefore some distance.

The amount lost depends on the boat, conditions and crew.

A light dinghy may accelerate again quickly.

A larger boat carrying several people may behave quite differently.

A long, narrow boat such as an A-Rater also has considerable momentum, but that certainly does not mean we can tack carelessly. Poor steering, excessive rudder movement, badly timed crew movement or slow sail handling can turn a tactical manoeuvre into a substantial loss.

So there is an important principle:

Do not tack simply because you can. Tack because the new tack offers something worth having.

Tack on a Header

One of the most important reasons to tack is a wind shift.

Imagine you are sailing close-hauled towards an upwind mark.

Initially your course looks good.

Then the wind changes direction and suddenly your bow is pointing further away from the mark.

You have been headed.

This is often a strong signal that it may be time to tack.

After tacking, that same wind shift may allow you to point much more directly towards the mark.

This is why good sailors are constantly comparing their course with the mark, the shoreline and other fixed references.

They are not merely steering the boat.

They are watching what the wind is doing.

Header or Lift? Learn to Recognise the Difference

Suppose you are sailing on starboard tack.

If the wind changes so that you can point more directly towards your destination without changing tack, you have been lifted.

Usually that is good news.

Stay on the lifted tack unless there is another reason to leave it.

If the wind changes so that you must steer further away from the destination to keep the sails working efficiently, you have been headed.

That may be the signal to tack.

A simple tactical rule therefore becomes:

Sail the lifts. Tack on the headers.

It is not a universal law, but it is an excellent principle to understand.

Do Not Tack Just Because Another Boat Tacks

This is remarkably tempting.

The boat ahead tacks.

Almost immediately, you tack too.

But why?

Perhaps its helm spotted a wind shift.

Perhaps they are avoiding another boat.

Perhaps they are heading for stronger wind.

Perhaps they are covering a competitor.

Or perhaps they have simply made a mistake.

One of the important stages in becoming a better sailor is learning to make your own tactical decisions.

When another boat tacks, ask:

"What have they seen?"

That is very different from automatically following them.

Look at the Water Before You Tack

This connects directly with one of the most useful skills in inland sailing: reading the water.

Suppose there is a darker, rippled patch of water 30 metres ahead and slightly to your left.

That may indicate stronger wind.

If you tack immediately, perhaps you sail away from it.

If you continue for another twenty seconds, perhaps you sail directly into it and gain both extra wind and a favourable shift.

The opposite can happen too.

Ahead may be a large glassy patch beneath trees.

The shortest route may lead directly into it.

Tacking away may involve sailing further geographically while actually reaching the mark sooner.

This is why sailing cannot be reduced to:

shortest distance = fastest route.

The fastest route is the one that combines distance, boat speed and wind most effectively.

River Sailing Makes the Decision Even More Interesting

On open water you may have enormous freedom about when to tack.

On the Thames, geography has other ideas.

There is only so much river.

Sooner or later there is a bank.

That creates what sailors often call a boundary.

You cannot continue indefinitely on the tack you prefer.

But that does not mean the best tactic is necessarily to sail right to the bank before tacking.

Quite the opposite.

If you sail too far into the edge of the river you may encounter:

disturbed or lighter wind close to trees;
wind shadows from buildings;
awkward bends;
shallow water;
moored boats;
other river traffic;
less room to complete the tack.

You may then be forced into a tack at exactly the moment you least want one.

Good tactical sailing involves anticipating that boundary.

Do not wait for the riverbank to make the decision for you.

Sometimes the Bank Can Help

There is another complication.

Current may not be identical across the entire river.

Depending on the river, its level, recent rainfall and local geography, current can vary across the channel.

If you are sailing against a significant current, there may be tactical value in considering where that current is weaker.

Conversely, if the current is helping you, stronger current may sometimes be advantageous.

But current should not be considered independently of wind.

There is little advantage in finding slightly weaker adverse current if doing so puts the boat into a large wind shadow.

You are constantly balancing competing factors:

wind + current + distance + traffic + position.

That is what makes inland racing so interesting.

Do Not Sail All the Way Into a Bad Corner

Imagine two boats approaching the side of the river.

Boat A continues until there is virtually nowhere left to go.

Then it tacks.

Unfortunately, it has entered disturbed air close to the trees. Boat speed falls before the tack, the tack itself is slow, and acceleration afterwards is poor.

Boat B tacks twenty metres earlier while still carrying good speed and sailing in cleaner wind.

Boat A technically sailed further on the original tack.

Boat B may nevertheless emerge ahead.

This is an important tactical lesson:

Using every metre of available water does not necessarily mean using the river efficiently.

Traffic Can Decide When You Tack

River sailing has another variable that open-water diagrams often overlook:

other river users.

A beautifully planned tack becomes irrelevant if a cruiser, narrowboat, paddleboarder, canoe or another racing boat occupies the space you intended to use.

Good sailors therefore think several moves ahead.

Rather than waiting until a collision-avoidance decision becomes urgent, ask:

What will the river look like in thirty seconds?

If continuing will put you into an awkward situation, an earlier tack may preserve far more tactical freedom.

That is particularly important in a fleet.

Sometimes You Tack Because of Another Racing Boat

Now we enter racing tactics.

Suppose another boat is ahead of you.

If you remain directly behind it, you may be sailing in disturbed air.

Tacking away could give you cleaner wind and an opportunity to find a different shift.

Alternatively, suppose you are ahead.

You might tack to remain between a close competitor and the next mark — a basic form of covering.

Suddenly the question "When should I tack?" is no longer simply about wind.

It is about position.

This is where sailing becomes rather like chess.

You are not merely thinking about where your boat is now.

You are thinking about where several boats may be after the next two or three moves.

The Layline Trap

Another common mistake is reaching the layline too early.

The layline is approximately the course from which you should be able to reach the mark without another tack.

It can be tempting to reach it as soon as possible.

That feels reassuring.

"Good. Now I can sail straight to the mark."

But arriving at the layline early can remove your options.

Suppose the wind shifts unfavourably.

You cannot tack further towards the mark because you are already committed.

Suppose the wind becomes lighter.

Again, your options are limited.

Suppose several boats arrive and begin affecting your wind.

You may have nowhere useful to escape.

Staying nearer the middle of the course for longer can preserve tactical choices.

Options have value.

A Simple Exercise: Give Every Tack a Reason

Here is an excellent exercise for sailors trying to improve.

Every time you tack, say — either aloud or mentally — why you are doing it.

For example:

"Header."

"Stronger wind on the other side."

"Avoiding the wind shadow."

"Approaching the boundary."

"Traffic ahead."

"Getting out of dirty air."

"Positioning for the mark."

"Covering the boat behind."

If you find yourself saying:

"I don't really know."

that is useful information.

You have identified an area of your sailing that can improve.

Try Delaying the Tack

There is another excellent training exercise.

Choose a familiar beat and deliberately experiment.

On one run, tack when you normally would.

On another, continue for perhaps another ten seconds before tacking.

Then try tacking ten seconds earlier.

Observe what happens.

Where do you cross the river?

What wind do you find?

What angle do you obtain?

Where do you end up relative to the mark?

This is much more useful than simply being told that there is one "correct" place to tack.

You begin developing tactical judgement.

The Crew Can Help

On a multi-crew boat, the helm should not have to observe everything.

Someone may be watching the wind.

Someone may be looking at boats behind.

Someone may notice traffic.

Someone may be judging the distance to the bank.

Someone may see the next gust arriving.

This becomes particularly relevant aboard Champagne, where communication between the crew matters enormously.

A simple warning such as:

"Pressure coming from the left."

or:

"Cruiser ahead — probably need to tack."

allows the helm to make the decision before it becomes urgent.

That produces a much better tack because everyone is prepared.

The Best Tack Is Often the One You Planned

A rushed tack tends to be expensive.

The helm suddenly decides to turn.

The crew are not ready.

Someone moves late.

The jib is released late.

The new sheet is pulled too slowly.

Weight remains on the wrong side.

The boat emerges slowly and badly balanced.

Compare that with:

"Ready about?"

Everyone knows what is coming.

The crew prepare.

The helm chooses the moment.

The boat turns smoothly.

The old sheet is released.

The new one comes in.

Crew weight moves at the correct moment.

The boat accelerates on the new tack.

Same manoeuvre.

Completely different result.

Sometimes the Correct Decision Is Not to Tack

Perhaps this is the most important lesson.

You receive a small header.

Should you tack?

Maybe.

But perhaps there is visibly stronger wind ahead.

Perhaps another boat would leave you in dirty air after the tack.

Perhaps traffic makes the new course awkward.

Perhaps you are only seconds from a larger expected shift.

Perhaps you would be forced to tack back almost immediately.

Good sailing is not about following tactical rules mechanically.

It is about weighing the evidence.

The rule "tack on a header" is useful.

The better question is:

"What do I gain by tacking now?"

From Boat Handling to Boat Thinking

Learning to tack is an essential part of learning to sail.

But eventually something changes.

You stop thinking:

Push the tiller. Move across. Change the sheets.

Those actions become automatic.

Your attention moves outside the boat.

You notice the ripples approaching across the water.

You notice that the boat is being headed.

You see that the opposite bank is becoming darker.

You realise the boat ahead is sailing into less wind.

You notice the cruiser that will occupy your route thirty seconds from now.

You begin thinking about where you want the boat to be next rather than simply where it is now.

That is a significant step in becoming a better sailor.

Because the real skill is no longer executing the manoeuvre.

It is deciding whether the manoeuvre is worth making.

Knowing how to tack gets you across the river.

Knowing when to tack can get you there first.

Next in the Improving Your Sailing series: we can take this idea one stage further and explore "When Should You NOT Tack?" — unnecessary tacks, chasing every tiny wind shift, losing speed through over-manoeuvring, and why sometimes patience is the fastest tactical decision.
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