Which Side of the River? Turning Local Knowledge Into Race Strategy

Learning to Race — From First Start to Better Results

The shortest route up a river is frequently not the fastest route.

Two boats round a mark together. One takes a direct route towards the next mark. The other moves towards the bank, makes an apparently unnecessary tack and sails further.

A few minutes later, the boat that travelled further is ahead.

Was it better sail trim? A faster boat? A fortunate gust?

Possibly. But on a river, the answer may lie in something more interesting: one crew recognised where the useful wind and water were, while the other simply aimed at the destination.

At Upper Thames Sailing Club, trees, buildings, bends, stream and other boats all influence the route. The challenge is to turn those observations into decisions before the opportunity has passed.

For me, learning to race Champagne is partly about learning the boat. It is also about learning to see the river differently.

The important question becomes:

Which route will get us to the next mark soonest—and what evidence supports that choice?

1. The River Is a Changing Racecourse

On a diagram, a sailing course looks reassuringly tidy: a start line, some marks and straight lines between them.

The river adds another layer.

One stretch may have relatively open wind. Further along, trees interrupt it. A building may create a patch of disturbed air. A bend changes the relationship between the river and the wind. Meanwhile, the strength and direction of the stream vary across the available water.

Upper Thames Sailing Club describes its sailing reach as extending between Bourne End and the islands below Marlow Lock. That setting provides plenty of opportunity to experience these interacting effects.

However, local knowledge should be more useful than a collection of instructions such as:

“Always go towards that bank.”

A better version is:

“That bank can work when the wind comes from this direction, provided there is still enough breeze beneath the trees.”

The first is a habit. The second is a strategy you can test.

Good local knowledge explains when a route works, why it works and when to abandon it.

2. Read the Windward Shore Before Choosing Your Side

Before looking for the best patch of water, look at what the wind has travelled over to reach it.

Has it crossed open ground? A line of mature trees? Houses? A gap between buildings?

Trees and buildings can reduce wind speed and create turbulence downwind. Their effects depend on their height, shape, spacing and the wind direction. The disturbed area does not necessarily end at the shoreline.

That produces a familiar river-sailing trap: the boat moves towards apparently sheltered water to escape the current, then loses the wind needed to make progress.

There is another complication. The bank closest to you is not necessarily the bank causing the problem. If the wind crosses the river, obstructions on the opposite shore may affect the air reaching your sails.

What to watch

Look for agreement between several clues:

• Ripples fading as they approach a particular stretch.

• Boats repeatedly slowing in the same area.

• Sails losing their shape or telltales becoming unsettled.

• Tree movement that differs from what you feel aboard.

• Better progress by boats sailing slightly further offshore.

One boat slowing could be poor handling. Several boats slowing in the same place are stronger evidence.

Choose your lane by the wind reaching the boat, rather than by how inviting the bank looks.

3. Pressure Can Matter More Than Pointing

In racing conversation, “pressure” usually means stronger wind.

When the breeze is light and uneven, a patch of useful pressure can be more valuable than a small improvement in sailing angle.

Imagine two boats beating towards a mark.

Boat A points a little higher but repeatedly enters weak, disturbed air.

Boat B sails a slightly less direct heading while keeping its sails drawing and its hull moving.

Boat B may arrive first because its average progress is better.

This does not mean sailing towards every gust. A gust has to be reachable, useful and worth the distance required to intercept it.

Ask:

1. Is that darker patch actually wind?

2. Is it moving towards us or away from us?

3. Can we reach it before it passes?

4. Will reaching it leave us with a useful route afterwards?

Darker water can also result from reflections, current or viewing angle. Treat a visible gust line as a clue, then check the response of boats within it.

A useful crew call

“More wind on the other side” is an observation.

“More wind approaching from the other side; one short tack could put us into it before the trees” is a possible plan.

The second gives the helm something to assess.

4. The Bank Can Save Current—and Cost the Race

Our earlier article, The Current Changes Everything, explored the difference between speed through the water and progress over the ground.

Choosing a side means applying that distinction.

Against the stream, a lane of weaker current can help. But a bank route must also provide enough wind, sufficient depth and room to manoeuvre.

Consider these simplified figures. They describe movement along an upstream leg, rather than total boat speed:

Lane	Upstream component through the water	Opposing stream	Net upstream progress
Open water	1.8 knots	0.7 knots	1.1 knots
Bank with useful wind	1.5 knots	0.2 knots	1.3 knots
Bank in a wind shadow	0.8 knots	0.2 knots	0.6 knots

The bank wins in the second situation and loses badly in the third.

For this aligned example:

Upstream progress = upstream component through the water - opposing current

The figures are illustrative, not measurements from a Champagne race.

The practical lesson is straightforward:

Weaker current helps only while you retain enough useful sailing speed.

Also remember that upstream is not necessarily upwind. An upstream leg might be a beat, reach or run, depending on the wind.

5. Downstream, Change the Question

When sailing downstream, stronger favourable current may become an advantage.

The route you avoided on the upstream leg could be worth seeking on the return.

But stronger stream does not automatically justify a long diversion. You still have to consider the distance, wind, traffic and cost of manoeuvres.

For a simplified route comparison:

Time taken = distance travelled / average speed over the ground

A 300-metre route averaging 1.5 metres per second takes 200 seconds.

A 360-metre route averaging 1.7 metres per second takes about 212 seconds.

The second route is faster over the ground but takes longer because the extra distance outweighs the gain.

There is a useful racing habit here: reassess the river after rounding the mark. The conditions that favoured one lane in one direction may favour another on the return.

6. Bends Change the Problem Ahead

A river bend changes the orientation of the sailing space relative to the wind.

Without any change in the broader wind direction, the next section may offer a different sailing angle. It may also expose the boat to different trees, buildings and gaps along the shore.

Current adds another complication. Flow often becomes stronger towards the outside of a bend, but depth, islands, structures and local river shape can alter the pattern.

“Inside slow, outside fast” is a starting hypothesis, not a reliable map.

Before reaching the bend, look beyond it:

• Which shore will be upwind of the next section?

• Where does the usable breeze appear to begin?

• Are boats ahead gaining or losing speed?

• Will our present lane give us room to turn or tack?

• Where will the stream carry us during the transition?

The best position approaching a bend may be the one that provides a clean exit, rather than the one that saves a few metres on entry.

Sail the next piece of river before you arrive in it.

7. Champagne: What the Tall Rig Can—and Cannot—Tell Us

Aboard Champagne, the height of the rig adds another dimension to reading the river.

An A-Rater can encounter air higher above the water than a smaller dinghy. That can sometimes help when the lower air is obstructed, but trees can be tall too, and disturbed airflow can affect a substantial part of the sail plan.

A tall mast is an opportunity to find useful wind. It is not immunity from wind shadows.

It also means that a nearby dinghy is an imperfect comparison. Its behaviour is useful evidence, but it may not be experiencing exactly the same air.

The questions aboard Champagne become:

• Is the upper sail still working while the lower sail struggles?

• Are we retaining speed through this patch?

• Is the stream carrying us towards a difficult position?

• Can we leave this lane before losing the room to tack?

My own published account of bringing Champagne into the Queen’s Cup story records the help Adrian Hart and Matthew from Scamp gave with setting the sails and adjusting the boom before our first sail. That is a useful reminder of how much there is to learn from people who know these boats.

The next step is to connect that boat-handling knowledge with the water ahead.

A well-set boat still needs somewhere useful to sail.

8. Three Racing Decisions to Practise Aboard Champagne

These are worked scenarios based on river-racing conditions, rather than accounts of particular recorded races.

Scenario A: The Tempting Upstream Bank

We are making steady progress against the stream. Near the bank, the water appears quieter, but trees stand upwind of the lane.

A rival moves close in and initially gains. Further along, its sails soften and its progress slows.

The useful response is to separate two effects: the bank is offering less current, but the next section appears to offer less wind.

A possible plan is to use the weaker stream while retaining a route back into clearer air before the shaded section.

The mistake would be to continue towards the bank simply because the first part worked.

The best lane can end halfway along a leg.

Scenario B: A Gust Approaches Across the River

We see rippled water approaching from the opposite side. A boat within it accelerates.

Crossing may help, but the crossing itself has a cost. It may involve stronger stream, disturbed air from another boat or an awkward arrival near the bank.

The decision should consider the whole sequence:

Reach the gust, use it, then leave it in a useful position.

If the gust is brief or moving away, maintaining our current lane may be better.

The mistake would be to chase yesterday’s opportunity—the patch that looked promising several moments ago.

Scenario C: The Fast Lane Has No Exit

There is useful wind and weaker stream near the bank. For the moment, everything looks favourable.

However, another boat is approaching, the bank is converging and the next tack will need space.

Continuing for a few extra seconds may surrender the ability to manoeuvre when we want to.

A slightly earlier tack could preserve speed and choice.

The mistake would be to judge the lane solely by its present benefit.

A lane is only as useful as your ability to leave it.

9. Use Other Boats as Moving Evidence

The fleet can help reveal the river.

Watch boats on different routes and compare their progress against fixed bank features. A boat may look lively through the water while making disappointing progress towards the mark.

The most useful comparisons are between similar boats in similar circumstances.

Ask:

• Are they travelling at a comparable sailing angle?

• Are their sails drawing?

• Have they just tacked?

• Are they in another boat’s wind shadow?

• Does the gain persist?

One boat gaining once is interesting. Several boats gaining repeatedly in the same lane are more persuasive.

Avoid following a familiar local sailor without understanding the reason. They may be responding to a short-lived opportunity, preparing for another boat or making a mistake themselves.

Copy the reasoning when you can identify it. Keep checking the result.

10. Turn Local Knowledge Into a Testable Plan

A useful plan can fit into three short statements:

Observation: The bank has weaker stream, but boats lose wind beside the trees.

Plan: Use the bank lane through the open section, then move out before the shelter.

Change trigger: Leave earlier if our sails stop drawing or boats outside start gaining.

That final statement matters. It prevents a sensible idea becoming an expensive commitment.

It also makes communication aboard clearer. Everyone knows what we are trying to achieve and what would make us reconsider.

Before the start, agree the likely advantage, the main risk and the point at which the decision needs reviewing.

You do not need a prediction for every metre of river. You need a reason for the next choice.

11. Build Your Own River Notebook

After racing, record a few observations while they are fresh.

Record	Useful detail
Wind direction	Where the wind came from relative to the reach
Wind strength	Whether pressure was steady or patchy
Stream	Observed differences between lanes
Location	A recognisable bank feature or section
Boat response	Speed retained, lost or recovered
Interpretation	Why the route appeared to help or hurt
Confidence	One observation or a repeated pattern

“The bank was good” is too vague.

“The bank lane helped against the stream until the wind faded beside the trees” is something you can investigate next time.

For Champagne, photographs and video can support that process. They may show when the sails lost shape, when another boat entered the same patch or how long a tack took.

Footage cannot measure unseen wind or current by itself, but it can help us ask better questions.

12. Five Questions Before Choosing a Side

During the race, reduce the detail to a manageable check:

1. Wind: Where is the most useful breeze?

2. Water: What is the stream doing in each lane?

3. Distance: Will the advantage repay the diversion?

4. Room: Can we tack, keep clear and leave the lane?

5. Evidence: What tells us the plan is still working?

Room includes depth, overhanging branches, moored boats and other river users. A promising racing route still has to be navigable and leave room to meet your obligations.

The aim is not to make the river predictable. It is to become quicker at recognising what matters.

Conclusion: Learn the Reason Behind the Route

The attraction of river racing is that the course keeps asking questions.

A bank offers shelter from the stream, then takes away the wind. A gust rewards a crossing, then moves on. A bend changes the next decision before the previous one is finished.

For me, that is part of the pleasure of sailing Champagne. There is the satisfaction of handling the boat better, alongside the quieter challenge of understanding why one patch of river works and another does not.

Local knowledge grows when we observe, form an explanation and test it again.

Next time you race, choose one section to study. Watch the wind, compare the lanes and notice where the boats actually gain. Afterwards, write down the reason you think it happened.

The shortest route is easy to draw. The fastest route has to be read from the river.

Follow Champagne’s sailing and racing journey at pmrsailing.uk.

Return to sailing website https://pmrsailing.uk/Lessons.html

 

The Current Changes Everything — Racing on a River

Learning to Race — From First Start to Better Results

You can be sailing faster than another boat and still watch it move ahead.

Your sails are drawing. The boat feels lively. There is a reassuring ripple along the hull. Yet a nearby rival, apparently moving more slowly through the water, is making better progress towards the next mark.

Before blaming your sail trim, look at the riverbank.

On a river, the water beneath you is moving too. The race takes place between marks anchored to the riverbed, so success depends on how effectively you move past those fixed positions.

For those of us sailing at Upper Thames Sailing Club, this makes current part of the racecourse itself. Wind, stream, banks, trees and other boats all have to fit into the same decision.

Aboard Champagne, our A-Rater, that is a particularly absorbing challenge. Her tall sail plan makes the wind impossible to ignore. The quieter influence beneath the hull deserves just as much attention.

Two Speeds, Two Different Stories

Start by separating two ideas:

• Speed through the water: how fast the hull moves relative to the surrounding water.
• Speed over the ground: how fast the boat moves relative to the riverbed and banks.

A GPS normally reports the second. A conventional water-speed log measures the first, subject to its accuracy and calibration. The RYA makes this same distinction in its navigation terminology. rya-enavigation.org

The underlying relationship is:

Velocity over the ground = velocity through the water + current velocity

Velocity includes direction. When the boat and stream are aligned, simple addition or subtraction works. When they cross at an angle, you must combine the directions too.

Imagine two boats travelling directly upstream. These are illustrative figures, not measurements from the Thames:

Boat	Speed through water	Opposing current	Upstream speed over ground
A, in stronger stream	2.0 knots	0.8 knots	1.2 knots
B, in weaker stream	1.8 knots	0.3 knots	1.5 knots

Boat A is sailing faster through the water. Boat B is moving upstream faster.

Over five minutes, that 0.3-knot advantage amounts to roughly 46 metres.

Boat B has found a better combination of boat speed and current.

One important distinction: upstream and upwind are different directions. Depending on the wind, the upstream leg might be a beat, a reach or a run.

Weak Current Can Have a Strong Effect

A gentle stream is easy to dismiss, particularly when there are no obvious swirls around the marks.

But small speeds accumulate over time:

Distance carried by current = current speed x time

At 0.1 metres per second, the water travels 30 metres in five minutes.

That does not mean every boat loses 30 metres to its rivals. If two boats experience exactly the same current for the same time, both receive the same displacement. The competitive difference comes from different current, different routes, different travel times and different progress towards fixed marks.

Weak current also becomes proportionally more important as the wind fades.

If your upstream component of speed through the water falls to match the opposing stream, you stop making upstream progress. The sails may still be drawing and the rudder may still respond, yet the bank barely moves.

A boat can be sailing quite normally while going nowhere along the course.

Read the River as Carefully as the Wind

Current is rarely identical across the whole width of a river.

Friction from the banks and bed influences the flow. Vegetation and channel shape also affect its distribution; research on natural channels illustrates how bank conditions can change velocity patterns. U.S. Geological Survey

A useful starting expectation is weaker flow near some margins and stronger flow in parts of the main channel. Treat that as a question to investigate. Bends, shallows, structures and local eddies can complicate the picture.

Useful clues include:

• Naturally floating leaves passing a fixed bank feature.
• Water streaming past an anchored buoy.
• Swirls or changes in surface texture near structures.
• Your own progress against the bank.
• Repeated gains and losses by boats using different lanes.

Ripples also reveal wind, so a darker patch of water is not automatically stronger current. A drifting leaf can be affected by wind too. Look for agreement between several clues.

For me, one of the attractions of Thames sailing is that the river rewards this sort of attention. The sail tells one story; the bank tells another. Good decisions come from reading both.

Upstream: The Bank Can Help — Until the Wind Disappears

When sailing against the stream, a lane of weaker current can be extremely valuable.

However, the bank may also bring trees, buildings, disturbed wind, shallows and very little room to tack.

Imagine making 1.6 knots upstream through the water in the main channel, against 0.6 knots of current. Your net upstream progress is 1.0 knot.

Move towards the bank and reduce the opposing stream to 0.2 knots. If you retain 1.4 knots of upstream movement through the water, your progress improves to 1.2 knots.

But if shelter reduces that movement to 0.8 knots, you make only 0.6 knots over the ground.

The weaker stream no longer compensates for the lost wind.

On a beat, use the upstream component of your boat’s movement, rather than simply subtracting current from total boat speed.

The practical question is:

Does the reduction in current outweigh the loss of useful sailing speed?

Aboard Champagne, I want to keep that question beside the temptation to follow a promising strip of quieter water. A bank lane needs enough wind, depth and room to remain useful.

Downstream: Helpful Flow Must Repay the Detour

When travelling downstream, stronger favourable current can improve progress. That often makes the main stream attractive.

But reaching it may require a detour, additional manoeuvres or sailing into another boat’s wind shadow.

The quickest route depends on total time:

Leg time = distance travelled / average speed over the ground

For a simplified direct downstream leg:

• A 300-metre route at 1.5 metres per second takes 200 seconds.
• A 360-metre route at 1.7 metres per second takes about 212 seconds.

The second route is faster over the ground but still takes longer.

These figures assume constant average speeds. Real river racing adds shifts, gusts, traffic and acceleration, but the principle remains useful.

Helpful current has to repay the cost of reaching it.

This connects directly to our earlier discussion of fleet positioning. A route towards one side needs a reason, and that reason must remain valid as conditions change.

Your Bow Does Not Show Your Track

Current can carry the boat sideways while it sails forwards.

Suppose you sail directly across a river at 1.0 metre per second relative to the water. The crossing is 20 metres, so it takes 20 seconds.

If the river flows downstream at 0.3 metres per second, you also move 6 metres downstream during the crossing.

Your bow can point at a gap while your actual track passes well below it.

To arrive opposite your starting point, you need an upstream component to your heading. The required angle depends on your speed and the stream.

The racing habit is simple:

Check where the boat is actually going, not just where it is pointing.

Compare an approaching mark with a fixed feature beyond it. Watch whether that alignment changes as you close. One glance is rarely enough.

Mark Approaches: Pointing at It Is Not Making It

Current makes the final approach to an anchored mark especially revealing.

When the stream carries you away from the mark

You may need extra up-current allowance. If your speed falls during a tack or in disturbed air, that allowance can disappear.

A mark which looked comfortably reachable can become an emergency extra tack.

When the stream carries you towards the mark

The final distance can close faster than expected. Prepare the crew and sails early enough to round under control.

When current crosses the approach

Aim sufficiently up-current to produce the required track, while allowing for the rounding side and other boats.

The correct allowance depends on the actual geometry. There is no universal instruction to aim upstream by a fixed number of boat lengths.

This also changes laylines. A still-water layline is an unreliable guide when current materially changes the boat’s track. Changes in stream or boat speed can change the approach again.

A useful call aboard Champagne would be:

“Are we making the mark over the ground?”

That question invites the crew to check the track, rather than agree that the bow looks promising.

Tacking Decisions: Protect Momentum and Choose the Lane

A tack costs speed. Against current, the resulting reduction in upstream progress can be particularly painful.

There are two decisions to make:

1. Is this tack worth the speed and distance it will cost?
2. Will it put us in a better combination of wind, current and clear air?

Short tacks near a bank may keep you in weaker stream, but repeated manoeuvres can consume the benefit. One longer tack may preserve speed while taking you into stronger adverse flow.

Neither approach wins automatically.

For Champagne, the useful evidence is how much speed we retain and how quickly we accelerate again in the conditions of the day.

There is an important piece of physics here: in uniform current, every nearby boat is being carried by the stream. The current does not suddenly push only the boat that tacks.

The tacking boat loses relative distance primarily because its sailing velocity changes during the manoeuvre. A slower passage also leaves it exposed to adverse stream for longer before reaching the fixed mark.

For practical purposes, watch how much progress the manoeuvre actually costs against the bank, then judge whether the new lane repays it.

Current Can Change the Wind You Sail In

Airflow over the sails depends on the boat’s movement relative to the air.

A moving water mass changes the wind experienced in a frame travelling with that water. The boat’s own motion then contributes to its apparent wind.

That is why crossing into a different stream can alter the wind angle or strength experienced aboard, even without a change in the wind relative to the bank.

This deserves care: it does not mean simply putting current on one side of the bow creates a free lift.

In uniform current, an otherwise symmetrical boat has no magical advantage merely because the stream is described as being on its “lee bow”. Changes in current, real wind shifts, boat performance and the course geometry are what need examining.

For a developing racer, the practical response is to notice the change, adjust trim and reassess the track.

The Start Line Moves Past You Even While You Wait

A start line is fixed to its marks. Your waiting position is in moving water.

Stream carrying you towards the line can erase a carefully judged gap. Stream carrying you away can make an apparently well-timed acceleration leave you late.

A useful pre-start check is to sail the intended approach and watch how the line closes in the actual stream.

This brings us back to time-on-distance: judge the approach relative to the line, with enough room and time to accelerate.

A Simple River-Reading Exercise

Before racing, in suitable conditions and clear water:

1. Identify the stream direction using fixed objects and several surface clues.
2. Sail comparable short stretches in two lanes, as traffic and room allow.
3. Compare progress against the bank, wind quality and freedom to manoeuvre.
4. Approach a mark and observe the difference between bow direction and track.
5. Record one observation and one question for next time.

If using GPS, remember it measures movement over the ground; GPS alone cannot separate current from boat speed through the water. Use any device in accordance with the event’s equipment rules.

Check the Environment Agency’s Thames stream warnings and the club’s decisions before sailing. Strong stream is a reason to reassess whether to go afloat, not merely an extra tactical challenge. GOV.UK

Conclusion: Race the Water as Well as the Wind

River racing asks us to hold two pictures in mind.

One shows the boat moving through the water: sail trim, balance, speed and handling.

The other shows that moving water carrying the boat past banks, anchored marks and the start line.

At Upper Thames, that combination is part of what makes the racing so absorbing. A short stretch of river can contain several different opportunities, and the best one can change with the wind.

With Champagne, my aim is to keep asking better questions:

Where is the useful wind? What is the stream doing here? Are we actually making the mark? Will the next tack improve our position?

The river rewards those questions.

The next time another boat edges ahead, look beyond its sails. The answer may be underneath it.

Follow Champagne and the Learning to Race series at pmrsailing.uk.

Return to sailing website https://pmrsailing.uk/Lessons.html

 

The Middle or the Corners? Understanding Fleet Positioning

Learning to Race — From First Start to Better Results

Winning the corner feels brilliant — until the wind shifts the other way.

You spot a promising patch of breeze near the bank. Most of the fleet stays further out, but you commit.

For a while, it looks inspired. Your sails fill, the boat accelerates and the opposition appears to slide backwards.

Then the breeze changes.

The boats in the middle tack towards the mark. You are still heading towards the bank, with little room left and an increasingly uncomfortable question:

How did such a good position become such a bad one?

Welcome to fleet positioning: deciding how far to separate from other boats, which opportunities justify that separation, and when to bring yourself back into the race.

On a narrow Thames reach, this becomes particularly interesting. “Going to the corner” might literally mean sailing towards the riverbank.

What Do We Mean by “The Corners”?

On an open-water beat, sailors often describe the far left and far right of the course as the corners. Going to a corner usually means committing heavily to one side before tacking back towards the windward mark.

On the river, the equivalent might be:

• Holding a tack almost to the bank.
• Following one bank while the fleet uses the other.
• Staying on the outside of a bend for a suspected wind advantage.
• Separating from the fleet to find less opposing current.

The important feature is commitment.

You are placing more of your race result in the hands of what happens on that particular side.

That can be a sound decision. But it deserves a better explanation than “I thought I might get lucky”.

Separation Makes Wind Shifts More Powerful

The sideways distance between boats creates what racing sailors call leverage.

Imagine two boats level with one another, both beating towards a mark. One is well to the left; the other is well to the right.

If the wind shifts left across the course, the boat on the left generally gains an upwind positional advantage. If it shifts right, the boat on the right benefits.

The greater their sideways separation, the larger the potential change in their relative positions.

UK Sailmakers describes this as an opportunity to make measured gains through separation, rather than always attempting one enormous move. UK Sailmakers News

A useful reminder is:

More separation means more exposure to being right — or wrong.

Neither boat has necessarily sailed faster. The wind has changed the value of where they are.

A simple practical example

Three boats begin a beat close together:

• Boat A works towards the left bank.
• Boat B stays in the central part of the fleet.
• Boat C works towards the right bank.

A favourable shift for the right arrives across the reach.

Boat C may make a substantial gain. Boat B experiences a smaller change relative to either extreme. Boat A suffers most.

If the next shift goes the other way, the picture may reverse — provided the boats still have enough course and manoeuvring room to respond.

That final condition matters. A shift returning later does not guarantee that it will rescue an earlier commitment.

The Middle Preserves Choices

The strongest argument for staying relatively central is flexibility.

With room on both sides, you can respond to a shift, move towards better pressure, avoid a wind shadow or adjust your approach to the mark.

At the edge, some of those choices disappear.

You might want to continue sailing on a favourable tack, but the bank prevents it. You might want to cross towards new pressure, but other boats block your route. You might reach the layline early and spend the rest of the beat watching opportunities develop somewhere you can no longer reach.

This connects directly with the previous article on laylines:

The earlier you commit to an edge, the sooner you may run out of useful decisions.

However, staying central does not mean repeatedly tacking for the sake of remaining in the middle. Every manoeuvre has a cost. Flexibility is valuable when you use it intelligently.

The Middle of the Course and the Middle of the Fleet Are Different

Suppose nearly every boat heads towards the right bank.

You remain in the geographical middle of the river. That sounds conservative, but you may now be substantially separated from your closest competitors.

Your position is central on the course and exposed relative to the fleet.

Conversely, you could be near one bank but surrounded by your principal rivals, all experiencing broadly similar conditions.

Ask two separate questions:

Where am I on the course?

Where am I relative to the boats I am racing?

The first concerns access to wind, current, marks and manoeuvring space. The second concerns how differently your race might develop from theirs.

You need both answers.

Staying in Touch Does Not Mean Following in Dirty Air

There is little comfort in remaining close to the fleet if you are sitting directly behind another boat with collapsing sails.

A useful position gives you:

• Clean enough air to maintain speed.
• Room to manoeuvre.
• A manageable separation from relevant competitors.
• Access to the next likely opportunity.

Sometimes that means taking a short tack away from the group and returning in a clearer lane. Sometimes it means accepting a slightly less attractive patch of water to keep the boat moving.

The aim is to remain connected to the race while sailing your own boat efficiently.

The RYA also highlights an important complication in mixed handicap fleets: nearby boats may have different ideal routes, and the boat beside you may not be your main rival on corrected time. Simply copying or covering it can distract you from sailing the fastest course. Racing

When Going to the Side Makes Sense

A central position is a useful response to uncertainty. It is not a universal answer.

Sometimes there is a clear reason to favour a side.

More reliable wind

You can see a band of pressure moving into one part of the reach. Boats already there are maintaining speed while those elsewhere struggle.

That is stronger evidence than one isolated dark patch on the water.

Look for confirmation: sail trim, heel, speed and whether the breeze appears likely to remain available when you arrive.

A developing wind trend

If observations suggest a persistent shift towards one side, positioning there may be justified.

But distinguish an established trend from a single change. One header does not prove that the wind will continue turning.

A current advantage

When sailing against the river’s flow, an area with less opposing current may offer a substantial benefit.

Near a bank, however, that advantage can come with weaker wind, shallower water, obstructions or extra manoeuvres. Around bends, the current pattern can become more complicated.

The relevant question is:

Will this route get me towards the mark faster overall?

A bend changes the next part of the race

On a river, the next stretch may present a different wind angle, shelter pattern or route to the mark.

A position that looks slightly inferior now could create a much better approach around the bend.

The RYA’s tactical guidance makes a useful distinction between decisions driven by wind shifts, advantageous areas of water and positioning relative to other boats. Identifying the dominant influence helps simplify the choice. Racing

A Thames Example: Less Current, Less Wind

Imagine an upstream beat on a narrow reach.

The main group is sailing in reasonable breeze further out. You notice an opportunity to use weaker opposing current nearer the bank.

You head across.

Initially, the choice works. Your progress over the ground improves.

Then you enter shelter from the trees. Boat speed falls, steering becomes less positive and you need to tack before reaching an obstruction.

Meanwhile, the boats further out continue making steady progress despite the stronger current.

Your original observation was correct: there was less flow near the bank.

The decision still failed because the loss of sailing speed outweighed the current advantage.

That is an important racing lesson:

Being right about one feature does not necessarily make the whole route right.

Try the comparison in reverse as well. A bank route with slightly weaker breeze may still win if the reduction in opposing current is large enough. The answer comes from observing the combined effect.

Your Position in the Race Changes the Risk

The same separation can be sensible in one situation and unnecessary in another.

Situation	A useful approach
Leading boats of similar performance	Limit unnecessary separation while maintaining speed and clean air.
Close to your main rivals	Look for small advantages without abandoning contact.
Behind, with plenty of racing remaining	Recover through clear air, good handling and evidence-based choices.
Behind near the finish	A larger split may be justified if following offers little chance to improve.
Uncertain about conditions	Preserve room to respond and gather more information.
Strong evidence of a better side	Move towards it deliberately, with a point at which you will reassess.

Being behind does not automatically make a corner gamble sensible.

There may be several places available through better tacks, a clean rounding and avoiding disturbed air. Those gains can disappear if frustration sends you towards a bank with no convincing advantage.

Equally, protecting a lead does not mean ignoring a clearly better route simply because nobody else has noticed it.

Take the Gain Before It Disappears

One of the hardest decisions is knowing when a successful move has done enough.

You separate towards a favourable side. The breeze arrives. You gain.

It is tempting to stay there and ask for more.

But if you keep extending away, you continue exposing yourself to the next change. Sometimes the better move is to tack back towards the fleet while your advantage is still available.

Think of it as converting an opportunity into a stronger position.

You have gained access to better air, moved ahead of a rival or created a useful crossing. You do not need to keep increasing the separation indefinitely.

A successful side move needs an exit plan as well as an entry plan.

What This Means Aboard Champagne

For me, this is one of the attractions of racing Champagne: the tactical decision has to become a practical decision for the whole crew.

A narrow opening on a sketch of the course may look less inviting when approaching it aboard a long A-Rater with a tall rig.

The questions become concrete:

• Have we room to complete the tack?
• What are the sails and boats ahead telling us about the breeze?
• Will we emerge in clear air?
• Are we approaching shelter?
• Where do we go if the expected advantage fails to appear?

I would rather have a clear reason for choosing a bank than an impressive explanation afterwards.

A useful crew conversation might be:

“There looks to be more pressure on the right. We’ll take a short move towards it, then reassess before we get committed to the bank.”

That gives everyone a purpose, an observation to check and a point at which the plan can change.

It also keeps the discussion focused on what happens next.

Try This in Your Next Race

Choose one beat and make fleet positioning your observation exercise.

1. Identify your reference boats.
Choose two or three boats of similar performance, or relevant handicap rivals.

2. State your reason before separating.
More pressure? Less opposing current? A developing shift? A clearer lane?

3. Identify the cost.
Extra distance, a tack, shelter, traffic or reduced freedom near the bank.

4. Set a reassessment point.
Use a visible feature, a change in pressure or a crossing opportunity. Avoid waiting until the bank makes the decision for you.

5. Review the decision afterwards.
Did the expected advantage appear? Did you use it? Could you have returned towards the fleet sooner?

Judge the reasoning as well as the result.

A sensible decision can lose to an unexpected change. A poor decision can occasionally win spectacularly. Looking only at finishing positions teaches the wrong lesson.

Conclusion: Choose How Much of Your Race to Commit

The middle and the corners offer different opportunities.

A central position preserves choices. A side position can exploit a real advantage. Greater separation increases how much you stand to gain or lose when conditions change.

The skill is deciding how much commitment the evidence deserves.

On the Thames, where a bank, a bend, a wind shadow and a patch of current may all influence the next hundred metres, that judgement becomes wonderfully absorbing.

Before your next move towards the edge, ask:

What am I expecting to gain, what could it cost, and how will I get back?

Winning the corner feels brilliant.

Learning when to leave it can produce a much better race.

Follow the Learning to Race series at pmrsailing.uk, alongside our continuing adventures aboard Champagne.

Return to sailing website https://pmrsailing.uk/Lessons.html

 

Laylines — Why Getting There Too Early Can Lose the Race

Reaching the layline feels reassuring — but you may have just run out of choices.

There is something wonderfully comforting about pointing towards a windward mark and thinking:

“We can make it from here.”

No more deciding when to tack. No more wondering which side to choose. Just sail towards the buoy and prepare to round.

Except racing rarely stays that simple.

The wind shifts. Another boat tacks ahead and takes your clean air. The current carries you sideways. Suddenly, what looked like a straightforward approach becomes a slow procession — or an awkward scramble to squeeze in two extra tacks.

Understanding laylines is about more than knowing when you can reach the mark.

It is about recognising when committing to that final approach will cost you the freedom to respond.

What Exactly Is a Layline?

Imagine a windward mark directly upwind.

You cannot sail straight towards it because that would mean sailing into the wind. Instead, you approach close-hauled on either port or starboard tack.

Now imagine extending those two possible final approaches backwards from the mark.

Those imaginary lines are the laylines.

A boat exactly on a layline can just reach and round the mark on that tack, assuming the conditions and its performance remain consistent. There are laylines downwind too, but this article concentrates on the windward mark.

A useful way to picture the arrangement is:

• Between the laylines: you still need some sailing on each tack before reaching the mark.

• On a layline: you can just make the final approach on one tack.

• Beyond a layline: you have gone farther to that side than you needed for the current conditions.

That last situation is called overstanding.

The layline is not a painted line on the water. It is your best estimate of where the final approach begins.

Why the Diagram Is Easier Than the Sailing

On paper, laylines look fixed and tidy.

On the water, their position depends on wind direction, the angle your boat can sail efficiently, leeway and current. Different boats need not share the same laylines.

This matters in mixed fleets.

A dinghy ahead might tack and comfortably make the mark. That does not prove that an A-Rater, another dinghy or a boat sailing in different current will make it from the same place.

Nor should you assume that the boat ahead has judged it correctly.

Perhaps its crew has overstood deliberately. Perhaps it is pinching and barely hanging on.

Another boat is evidence, rather than an answer.

For me, this is part of the attraction of learning to race Champagne. The challenge is to develop judgement about our own boat, rather than simply copy the track of somebody else.

The Trap: Committing While the Mark Is Still Far Away

Imagine two boats approaching the upper part of a beat.

Boat A heads all the way out to the starboard layline, tacks and settles onto a long final approach.

Boat B stays a little farther inside, with a short amount of sailing still required on the other tack.

Boat A’s crew feels reassured. Boat B’s crew still has a decision to make.

But that remaining decision is valuable.

Boat B has kept some freedom to respond to changing conditions. Boat A has committed much earlier.

An early layline approach exposes you to changes for longer: a shift may leave you overstanding or unable to fetch, while traffic can leave you sailing in disturbed air with an expensive escape route.

The problem is not reaching a layline.

The problem is reaching it so early that you spend a large part of the beat with fewer useful choices.

What Happens If the Wind Lifts?

Suppose Boat A is just able to make the mark on starboard tack.

Then the wind lifts it.

The boat can now point higher, and the mark lies below its new close-hauled course. It can ease sheets and sail towards the buoy.

That sounds pleasant — and it may feel fast.

But Boat B, still inside the old layline, may now be able to tack and fetch the mark too. It no longer needs to sail as far out as Boat A did.

Boat A’s earlier journey to the outside has become unnecessary distance.

The lift has helped both boats sail towards the mark, but Boat B retained the position to use it more efficiently.

Sailing faster towards a buoy does not prove that you took the fastest route to it.

What Happens If the Wind Heads?

Now imagine the opposite.

Boat A has committed to its final approach, but the wind heads it. It can no longer sail directly to the mark at a sustainable close-hauled angle.

The tempting response is to squeeze the tiller over and try to point higher.

For a few seconds, that may appear to work. Then speed falls, the foils become less effective and leeway increases.

The boat may end up making even less progress.

If the header persists, an extra pair of tacks may be necessary. Meanwhile, a boat inside the laylines may be better placed to tack and use the new wind direction.

This connects directly with our earlier discussion of oscillating and persistent shifts: you still need to interpret what the wind is doing. Reaching a layline does not make that question disappear.

It can simply make the answer harder to act on.

Dirty Air: When the Final Approach Becomes a Queue

There is another reason the reassuring layline can become uncomfortable.

Other boats want to use it too.

You tack onto what looks like a clean approach. A boat ahead then tacks into your lane. Your sails lose pressure and your speed drops.

You could tack away — but now you are heading away from the direct approach and will probably need another tack to return.

You could continue — but that may mean accepting disturbed air all the way to the mark.

This is why a slightly longer route with clear air can sometimes beat a geometrically tidy approach in a queue. The decision depends on the size of the detour and how badly the other boats are affecting you.

With an A-Rater’s large sail plan, the relationship between positioning and clean air deserves particular attention.

Aboard Champagne, I want the approach conversation to include:

“Will we still have usable wind?”

That is a different question from simply asking whether we can point at the buoy.

Overstanding: The Hidden Cost of “Just to Be Safe”

A small allowance can be sensible.

Repeatedly sailing a long way beyond the estimated layline “to be certain” can become expensive.

Consider a deliberately simplified example: flat water, no current, steady wind and close-hauled tracks at 45 degrees to the upwind direction.

A boat continues 20 metres beyond the correct tacking point. After tacking, it can reach directly towards the mark.

If the original tacking point was 100 metres from the mark, the new direct approach is approximately 102 metres long. The boat has sailed:

20 + 102 = 122 metres

instead of approximately 100 metres.

That is about 22 metres extra. At an illustrative speed of 2 metres per second:

Extra time = extra distance / speed

Extra time = 22 / 2 = approximately 11 seconds

The exact result changes with the geometry, speed and conditions. It is not a universal overstanding formula.

But it demonstrates why “only a little farther” can matter in a close race.

River Racing: Your Bow Can Point at the Mark While Your Track Misses It

On the Thames, the boat’s heading tells only part of the story.

Your movement over the ground combines movement through the water with the river’s flow.

In plain text:

Ground velocity = boat velocity through the water + current velocity

Those velocities have directions as well as speeds.

If current carries you away from the mark, you need to allow for it. If it carries you towards the mark, sailing to the position you would use in still water may cause you to overstand.

For an illustrative scale, a sideways current component of 0.3 metres per second produces:

Sideways displacement = 0.3 x 60 = 18 metres in one minute

That assumes a constant current component, but it shows why a short final approach can change substantially.

On a river, current may also vary across the course. A boat approaching through stronger flow cannot automatically use the judgement of one nearer the bank.

The useful question is:

“Are we tracking towards a successful rounding?”

Looking at the buoy over the bow is not enough.

When Getting There Early Can Be Sensible

“Stay off the layline” is a useful warning, but it is not an absolute rule.

An earlier commitment may be justified when:

• A reliable wind or current advantage makes that side worthwhile.

• A bank or obstruction limits your next move.

• A clear approach is available now, with congestion developing elsewhere.

• Conditions make another tack particularly costly.

• A modest margin gives a more reliable rounding.

For example, current setting boats away from the mark can justify allowing extra room rather than joining a group that is struggling to fetch.

The distinction is between a deliberate allowance and an unexamined habit.

Choose the margin for a reason.

Do Not Replace an Early Commitment with a Last-Second Gamble

There is a trap at the other extreme.

Trying to preserve every possible option until the final moment can leave you approaching on port tack, searching for a gap in a line of starboard-tack boats.

Tacking near the mark also brings additional rules considerations. Under the current rules, rule 18.3 places specific restrictions on a boat tacking from port to starboard in the zone at a mark to be left to port.

The aim is to leave enough room and time to complete a controlled, lawful approach.

Tactical flexibility is valuable only if you can turn it into a workable rounding.

A Better Conversation Aboard Champagne

I find it useful to turn a complicated idea into a few questions the crew can actually use.

Rather than asking only:

“Can we make it?”

I would like the conversation aboard Champagne to become:

1. Can we make it at normal speed, without pinching?

2. What is the current doing to our track?

3. Will we have clear air?

4. What happens if the wind changes?

5. Where is our escape route?

These questions encourage the crew to look beyond the immediate comfort of pointing towards the mark.

A useful call might be:

“We look close, but the current is setting us down. Allow a little more.”

Or:

“We can fetch, but that boat will cover us. Let’s protect our air.”

The purpose is to make an earlier, better-informed decision.

Try This Before Your Next Race

Choose a practice mark with plenty of room and little traffic.

Make an approach on each tack. Before the final tack, call whether you think you are short, exactly on the layline or comfortably beyond it.

Then test the judgement.

Sail at your normal close-hauled angle and speed. Avoid pinching to make your prediction appear correct.

Afterwards, ask:

• Did we fetch comfortably?

• Did we need to bear away significantly?

• Did current move us sideways?

• Did the wind change during the approach?

• What clue should we use next time?

Repeat in different conditions.

The aim is to build a feel for your boat and learn how much confidence to place in the estimate.

Conclusion: Aim for a Good Approach, Not an Early Promise

The layline offers an appealing promise:

From here, the decisions are over.

But the race continues. Wind changes, current varies and other boats interfere.

Commit too early and you may spend the final part of the beat defending a decision that has stopped working. Wait too long and you may create a rushed, congested rounding.

The skill is judging when the remaining flexibility is worth more than the certainty of the final approach.

For those of us developing our racing aboard Champagne, that is a useful lesson: look beyond whether the boat can reach the mark and consider the quality of the route.

Reach the layline with a plan — and before then, keep your choices working for you.

Follow the Learning to Race — From First Start to Better Results series at pmrsailing.uk, as we explore the decisions that turn boat speed into better racing.

Return to sailing website https://pmrsailing.uk/Lessons.html

 

Dirty Air — Why Following Another Boat Can Feel Like Sailing Into a Hole

Learning to Race — From First Start to Better Results

The boat ahead isn’t only blocking your route — it may be stealing your wind.

You are sailing towards the windward mark. The boat feels balanced, the sails are drawing and you seem to be keeping pace with the fleet.

Then another boat crosses ahead and tacks.

Nothing obvious changes on the river. There is still breeze on the water. Yet your boat suddenly feels lifeless. The jib telltales become restless, the mainsail loses pressure and the boat ahead begins to pull away.

You try pointing higher to follow it. That makes things worse.

You pull the sheets tighter. That does not help either.

It feels as though you have sailed into a hole.

You may have entered dirty air: airflow disturbed by another boat’s sails. Learning to recognise it — and deciding when and how to escape — is an important step from simply sailing the course to racing it effectively.

What Is Dirty Air?

Sails generate force by changing the movement of air around them. The air leaving a sail has therefore been affected by that sail.

For another boat nearby, this can mean:

• reduced wind speed;

• a different wind direction;

• turbulent, uneven airflow.

These effects overlap, but they are not identical. Sometimes your sails lose pressure. Sometimes they remain reasonably full, yet you can no longer point as high as a neighbouring boat.

A boat can therefore damage your performance before your sails visibly collapse. Upwind, slower and headed airflow can leave you sailing both lower and slower than your rival.

Dirty air is a problem with the wind reaching your boat. Good sail trim still matters, but it cannot restore the undisturbed airflow another boat has taken away.

A Wind Shadow Is Not Simply Behind the Transom

Imagine sheltering behind a building on a windy day. You may feel less wind, but also sudden swirls and changes in direction.

A sailboat produces a moving, more complicated version of that disturbance.

However, its wind shadow does not necessarily follow its track through the water.

That distinction matters:

A boat’s water wake follows its passage. Its disturbed airflow extends downwind from its rig.

The apparent wind — the wind experienced by the moving boat — provides a useful starting point for understanding where that disturbance travels. Sail deflection and turbulence complicate the exact shape.

Consequently, a boat ahead and to windward can be affecting you even though you are nowhere near its water wake.

There is no universal boundary measured in boat lengths. Rig size, wind strength, sailing angle and relative positions all matter.

The useful question is:

“Is the air reaching my sails passing through the influence of that boat first?”

Wind Shadows and Backwinding: What Is the Difference?

Racing conversations often use “dirty air”, “blanketing” and “backwinding” rather loosely. It helps to separate the main ideas.

Wind shadow or blanketing

Another boat lies between your rig and the incoming wind. Your sails receive weaker, disturbed airflow.

You may notice reduced heel, less pressure in the sheets and a loss of speed.

Backwinding and a local header

A nearby boat can also deflect the wind so that it reaches your sails from a less favourable direction.

On a beat, this can feel like a header: you need to bear away to keep the sails drawing.

A particularly frustrating position is close to windward and slightly behind another boat. The leeward boat’s influence can make it difficult to maintain your lane. Trying to hold its heading may leave your sails luffing and your speed falling.

Backwinding can also describe the front of a mainsail being pushed inward by airflow from its own jib. That is a separate interaction within one boat’s sail plan.

The practical lesson is straightforward:

Another boat can hurt your sailing angle as well as your speed.

Why “Just Behind” Can Become “Much Further Behind”

At first, staying close to the boat ahead feels sensible. You are following a successful route and keeping your opponent within reach.

But consider an illustrative example.

Two boats would otherwise make the same progress towards the windward mark. One enters disturbed air and loses 0.3 metres per second of progress towards it.

After one minute:

Additional distance lost = 0.3 x 60 = 18 metres

Those figures are an example, rather than a prediction for every boat. They show why a small, sustained disadvantage matters.

The loss may also become harder to reverse:

1. Reduced sail force slows the boat.

2. The slower boat has less effective steering and may make more leeway.

3. The helm tries to recover height by pointing higher.

4. The sails lose further drive.

5. The boat ahead continues towards the mark in better air.

A small initial gap becomes a substantial separation.

Meanwhile, a third boat sailing a slightly longer route in clear air may pass both your position and your expectations.

Close to the leader does not always mean close to matching the leader’s performance.

How to Recognise Dirty Air Before You Lose Too Much

No single symptom proves that another boat is responsible. River sailing includes genuine lulls, bank shelter, shifts and changes in current.

Look for several clues together.

Your boat changes as another boat moves into position

You were sailing comfortably. Another boat crosses, tacks or establishes itself ahead and to windward. Your performance then deteriorates.

The timing is a useful clue.

Nearby boats retain pressure

Your boat becomes upright and sluggish while boats outside the suspected shadow remain powered up.

They may have access to better air.

You cannot match the other boat’s heading

You can keep the jib drawing only by sailing lower, despite having held a better angle moments earlier.

The telltales become difficult to settle

Small steering or trimming adjustments no longer produce the response you expect.

The boat recovers after you create separation

Pressure returns, steering improves and the sails settle as you move away.

That recovery is valuable feedback. Remember the relative positions that caused the problem.

Escaping Upwind: Choose a Route Back to Useful Air

The answer is not automatically “tack immediately”.

An escape has a cost, and the new position needs to be better than the old one.

Option 1: Tack into an open lane

If you are losing steadily and the opposite tack offers clear air, tacking away may be the simplest solution.

Before committing, check:

• other boats and room to complete the manoeuvre;

• the bank, shallows and available water;

• current and wind pressure on the new route;

• whether you are exchanging one boat’s shadow for another.

Tack with enough speed to complete the manoeuvre cleanly, then allow the boat to accelerate.

Do not rush to tack back simply because the leader is still sailing the other way. First establish that you have recovered useful air.

Option 2: Bear away to build speed and separation

If you are near the edge of a disturbed area, bearing away slightly may help you accelerate and work clear.

This can be useful when you have open water to leeward and want to continue on the same tack.

But it is not a guaranteed escape. Sailing lower beneath a boat that remains directly to windward may leave you in its shadow for longer.

Judge the result by returning pressure and speed.

Option 3: Hold briefly for an opening

Sometimes the disruption will be short-lived.

A crossing boat may continue away. A boat ahead may be about to tack at the bank. You may be seconds from rounding a mark.

In those situations, a costly manoeuvre could lose more than a brief period of dirty air.

There is a difference between waiting for a specific opening and hoping that a persistent problem will disappear.

Ask:

“What is about to change that will give us better air?”

If there is no convincing answer, start planning an escape.

Do Not Try to Solve Everything With the Sheets

When a boat slows, pulling harder on the sheets is an understandable reaction.

But excessive sheeting can make an underpowered boat harder to accelerate.

Instead:

• steer to the airflow you actually have;

• adjust trim to keep the sails working;

• keep the boat balanced;

• minimise unnecessary rudder movement;

• identify a route to better air.

On emerging from the disturbance, rebuild speed before asking the boat to point at its highest useful angle.

Recover drive, then recover height.

Downwind: The Boat Behind Can Take Your Wind

On a beat, we tend to watch the boats ahead.

On a run, the threat may come from astern.

With the wind coming from behind, a following boat can place its sails between your rig and the incoming breeze. It may then gain as your sails lose pressure.

This is one reason a comfortable lead can begin shrinking unexpectedly on a downwind leg.

On reaches and faster downwind angles, the apparent wind may be well forward of directly astern. The dangerous position therefore changes with the boats and their sailing angles. Avoiding downwind wind shadows is a positioning skill in its own right.

Keep looking behind as well as ahead.

If another boat is moving into a position that could blanket you, consider creating separation while you still have speed. A course adjustment or a planned gybe may help, depending on the course, traffic and available water.

A late escape from a collapsed sail is usually harder than an early decision made while the boat is still moving well.

Why This Matters So Much Around an A-Rater

An A-Rater’s tall rig and substantial sail plan make airflow a particularly interesting part of river racing.

With Champagne, the lesson extends beyond the narrow hull visible on the water. The rig occupies a much larger space, and its influence on neighbouring boats deserves attention.

For a smaller boat nearby, that large sail plan is a good reason to anticipate possible disturbance rather than wait for a sudden loss of drive.

That does not give Champagne a fixed, invisible exclusion zone. The affected area changes with the conditions and relative positions.

Nor does a large rig make an A-Rater immune to dirty air. Champagne still needs access to useful airflow, and the crew still needs to recognise when another boat is compromising it.

For me, this is one of the most absorbing aspects of racing her: the contest takes place in the air above the river as well as on its surface.

The space between the hulls tells only part of the story.

On the Thames, Clear Air Must Fit the River

On open water, escaping may involve a relatively straightforward tack into space.

On the Thames, that space can be limited.

A tempting escape route may lead towards:

• shelter from trees or buildings;

• stronger adverse current;

• shallow water;

• another group of boats;

• a bank that forces an early tack.

Imagine following a boat along a sheltered bank to avoid stronger current in the middle.

You begin losing pressure in its dirty air. Tacking towards the centre might restore the breeze, but expose you to more stream. Continuing along the bank might protect you from the current while leaving you unable to sail efficiently.

There is no automatic answer.

You must compare the likely losses: dirty air, current, extra distance and manoeuvring.

This connects directly with the earlier distinction between strategy and tactics. Your preferred route along the bank is the strategy. Another boat compromising your airflow creates the tactical problem.

A good route still needs a workable sailing lane.

Do Not Mistake Another Boat’s Header for a Change Across the Course

In the previous articles, we explored headers, lifts and the difference between oscillating and persistent shifts.

Dirty air adds another question:

Has the wind changed across the course, or only where I am sailing?

If your apparent header begins when another boat settles close ahead, be cautious about treating it as evidence of a wider wind shift.

Look at boats in clear air. Are their headings changing too? Does your original angle return when you separate?

A local airflow problem may need a local escape. It does not necessarily justify abandoning your whole race plan.

A Simple Practice Exercise: Find the Edge

Two boats can explore this outside a race, in suitable open water.

Agree the exercise beforehand, keep ample separation and avoid other traffic.

1. Sail on the same tack with steady trim and reasonably consistent speed.

2. Position one boat ahead and to windward of the other.

3. Let the following crew note changes in pressure, telltales, heading and speed.

4. Gradually create separation and observe when the boat recovers.

5. Swap roles and repeat.

The aim is not to sail dangerously close or establish a universal distance.

It is to connect relative position with what the boat feels like.

Afterwards, discuss:

• Did pointing ability change before speed?

• How obvious was the loss of pressure?

• Which route restored useful air most efficiently?

• Did the result change when the breeze changed?

Those observations are far more useful than memorising an arbitrary number of boat lengths.

The Personal Lesson: Stop Following and Start Assessing

Following another boat is reassuring. It removes the need to choose a route and makes the next decision feel less urgent.

Yet racing requires us to question that comfort.

Am I following because this remains the best route, or because I have stopped assessing my own situation?

Aboard Champagne, the question I want us to keep asking is:

“Are we sailing in the air we need, or accepting the air another boat leaves us?”

That encourages the whole crew to contribute. One person may notice pressure returning farther out. Another may see a gap opening. The helm may feel the loss of steering response first.

Recognising the problem together makes an earlier, calmer decision possible.

Conclusion: Find the Wind That Lets Your Boat Work

Dirty air can be deceptive. Your sails may remain full, your course may look sensible and the boat ahead may seem only a little faster.

But weaker, deflected airflow can steadily turn a small gap into a large one.

Recognise the symptoms. Compare your boat with those in clear air. Decide whether to tack, create separation or wait briefly for a definite opening.

Above all, choose where you can sail effectively.

The next time your boat feels as though it has fallen into a hole, look beyond the sheets and tiller. The way out may be a better patch of air.

Follow the Learning to Race series and Champagne’s progress at pmrsailing.uk.

Return to sailing website https://pmrsailing.uk/Lessons.html