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Vela2D

Sail a real race, on your local water.

A browser sailing simulator built on real racecourses — currently four real Florida venues. The wind, the current and the coastline come from the actual place. You sail a single-handed dinghy against an AI fleet, from the five-minute gun to the finish.

Four real venuesSnapshots of real wind and current, soon connected to live weatherLeaderboards comingFree

What you're sailing

If you race a Laser or an ILCA, this is your boat. The hull geometry, the sail plan and the control lines are modelled on it, and the physics are built to reproduce how that hull actually behaves: how it accelerates, how it heels, how it slides sideways when you get it wrong. No crew, no spinnaker, and famously tender. Everything that makes the boat fast also makes it want to tip over, which is the whole game.

You have six controls plus your own body weight, and they matter in roughly this order:

  • Tiller — steering.
  • Mainsheet — sail in or out. Your primary throttle and your primary brake.
  • Hiking — your body is the ballast. Leaning out is how you keep the boat flat.
  • Vang — pulls the boom down, tightening the leech. On = powered and tippy.
  • Cunningham — pulls the luff down, flattening the sail and dragging the draft forward. For breeze.
  • Outhaul — flattens the bottom of the sail. For breeze.
  • Centreboard — down for upwind grip, up a little downwind to reduce drag.

If you're new: sail your first race on the tiller, the mainsheet and hiking. Focus on those three. The other four are refinements and they genuinely do change how the boat goes — but as long as you don't pick the strongest wind, you'll be fine without them.

Controls

On a phone (start here)

Drag the on-screen helm to steer. MAIN IN and EASE trim the sail; HIKE gets your weight out. Two-finger pinch zooms. The finer controls sit in a compact grid you can ignore at first.

Tap ▶ Start to begin the five-minute sequence — or tap Skip to jump straight to the one-minute gun and start racing almost immediately.

On a desktop

Key Does
Tiller (reversed: bow turns opposite)
W SMainsheet (trim in / ease)
E DVang (on / off)
R FCunningham (on / off)
Q AOuthaul (flat / full)
Z XDaggerboard (down / up)
Shift (hold)Hike out
+ , wheelZoom
] [Scrub tide clock (forward / back in time)
, .Wind speed − / +
; 'Wind veer (port / stbd)
SpaceStart sequence
EnterSkip to 1:00, again to the gun
BackspaceReset course
1 2 3Wind scenario
MMinimap zoom
LLearning / Pro mode
PMute / unmute audio
CCycle race course preset
TCycle AI difficulty (Easy/Med/Hard)

The tiller is backwards. On purpose.

Push the tiller right and the bow turns left — the way a real tiller works.

How a race works

The start

Racing starts with a five-minute countdown: 5 — 4 — 1 — 0. You're not waiting around; you're jockeying for position so that when the gun fires you cross the line at full speed, on the tack you want, with clear air. Getting this right is most of a race.

Cross early and you're OCS — On Course Side. You have to sail back below the line before you can start properly, which is expensive. Most beginners start ten seconds late; a few start OCS. Aim to be moving fast and arriving at the line as the gun goes.

In a hurry? Skip jumps you to the one-minute gun.

The course

Every venue races a windward-leeward course: beat upwind to a mark, turn, run back down, repeat. It's the standard racing course worldwide because it tests the two things that matter — pointing ability and downwind speed.

Some venues use a gate at the bottom instead of a single leeward mark: two marks you sail between and round either one. Gates exist because in real current a single leeward mark can be brutally hard to round — which is exactly why St. Augustine and Palm Beach use one.

How you're scored

Low Point scoring: your finishing place is your score, so 1st = 1 point, 2nd = 2, and lowest wins. Fail to finish — DNF, DNS or DSQ — and you score one more than the number of boats that started, which is why finishing badly always beats not finishing. Your elapsed time is recorded too, and that's what the share line quotes.

Rounding a mark — and which side

Every mark is rounded to port: you leave it on your left, so the whole course turns counterclockwise. The one exception is the right-hand mark of a leeward gate, which you round to starboard — that's the point of a gate, you pick a side and round it the way it faces. Round a mark the wrong way and the leg doesn't count; you have to go back and do it again. The minimap shows which mark is next.

The rule of thumb is wide in, tight out. Approach a little wider than feels natural, then carve so you exit close to the mark already on your new course. Rounding tight-then-wide is the classic error: you finish several boat lengths to leeward of where you should be, and on an upwind leg you pay for it the whole way.

The rules

What Vela2D enforces

Touching a mark (RRS 31). Hit a mark and you owe a One-Turn Penalty — a full 360° containing one genuine tack and one genuine gybe, in the same direction. Weaving back and forth doesn't count. This is the real penalty from the real rulebook (RRS 44.1 and 44.2).

Finishing with a penalty still owed = DSQ. Do your turn when you get it.

OCS. Over the line at the gun, and you must return below it before starting.

Correct side, correct order. Miss a mark or round it the wrong way and the leg doesn't count.

What real racing adds (and Vela2D doesn't simulate yet)

Vela2D does not yet model right-of-way between boats. You can't foul the AI fleet and they can't foul you. There are no protests. On real water these rules govern every one of those encounters:

  • Rule 10 — opposite tacks. A port-tack boat keeps clear of a starboard-tack boat. The big one, and the reason "Starboard!" is the most-shouted word on a racecourse.
  • Rule 11 — same tack, overlapped. The windward boat keeps clear of the leeward boat.
  • Rule 12 — same tack, not overlapped. The boat clear astern keeps clear of the boat clear ahead.
  • Rule 13 — while tacking. A boat tacking keeps clear until she's on a close-hauled course.
  • Rule 18 — mark-room. Inside the three-hull-length zone, an overlapped inside boat is entitled to room to round.

These are next on the build list — right-of-way, with the AI fleet obeying it too. Until then, Vela2D will teach you boat handling, tactics, current and the start, but not the right-of-way rules.

Cite: World Sailing, Racing Rules of Sailing 2025–2028.

What isn't finished yet

An honest list. It gets shorter over time.

Right-of-way between boats — as above. Next on the list.

The AI fleet doesn't always complete the course. In stronger current — St. Augustine especially, and in light air — a boat can get set past a mark, fail to register the rounding, and end up scored DNF. You'll see it as a boat marked "—" in the standings. Your own race scores correctly. Being fixed.

The start is the only pre-race phase. No general recalls, no black flag, no shortened course.

Weather is realistic, not live. Each venue's wind comes from that location's observed climatology, and the tidal current is a modelled scenario you pick — not today's forecast. Live weather is on the roadmap.

How to actually go fast

Flat is fast

Sailed well upwind in about ten knots, this boat sits at roughly 10–15° of heel — not on its ear. Excess heel costs you three ways at once: the hull shape gets less efficient, you slide sideways more, and the helm loads up so the rudder drags like a brake. If you're heeled a long way over and fighting the tiller, you aren't going fast. You're going sideways, slowly.

Ease, hike, trim — in that order

A puff hits and the boat lays over. Every time, in this sequence:

  1. Ease the mainsheet. Instant, and it spills power immediately.
  2. Hike hard. Get your weight out.
  3. Trim back in as the boat comes up.

Beginners do it backwards — hike first, get overwhelmed, capsize with the sheet still cleated. Ease first. You can always trim back in; you can't un-capsize quickly.

The vang is your gearbox

Vang on tightens the leech: full power, top of the sail working hard. Vang off lets the top twist open and spill wind. Because the top of the sail has the longest lever over the boat, twisting it off dumps heeling moment far faster than it dumps drive. Vang on for power in flat water, vang off when you're overpowered.

Cunningham and outhaul both flatten the sail, which is what you want as the breeze builds. In light air, ease everything — a flat sail in five knots is a slow sail.

You cannot sail straight upwind

Roughly 45° either side of the wind is a no-go zone. To get upwind you beat — zigzag through a series of tacks. The green and red tracks on the water show your close-hauled headings on each tack.

Watch VMG, not speed

VMG is velocity made good — how fast you're actually closing on the mark, not how fast the water is going past. Point too high and you'll pinch: the boat feels fine, speed drops, VMG collapses. Foot off too far and you're quick but sailing a longer course. The fast groove is narrow, and VMG is the only number that tells you when you're in it.

The coaching cues say the same thing in words: LUFFING (too high), IN THE GROOVE (right), EASE — stalled (sheeted too hard), TRIM IN (too loose).

Respect the current

Moving water pushes you sideways whether you like it or not. If the ebb is setting north at a knot and a half, you must aim above the mark to arrive at it. The SET and DRIFT readout on the wind rose tells you which way the water is going and how fast.

Current also decides tactics. Sailing against the tide? Get out of the main channel into the shallows where it runs weaker. Sailing with it? Stay in the deep water and take the free ride.

Don't overstand the layline

The layline is the line from which you can fetch the mark without another tack. Tack onto it too early and you sail extra distance for nothing; sail past it and every metre beyond is waste. Aim to arrive on the layline late, not early.

Four real places

Each venue is built from the real coastline (OpenStreetMap), that location's observed wind climatology, and its real tidal current. I've done my best to get the direction and the relative strength right — but I could be wrong. If it doesn't match the water you sail, tell me.

The Rudder Club of Jacksonville

Orange Park, St. Johns River

Tannic brown river water and a wide, forgiving racecourse. The St. Johns is one of the few major American rivers that flows north, so the ebb carries you downstream toward Mayport and the flood pushes you back up. Current is gentle here — the mildest of the four — which makes Rudder the place to learn.

Winds: summer sea breeze ESE ~10 kn · winter frontal NW 18 kn · a light ENE day at 6.

Course: windward-leeward with a gate.

The Florida Yacht Club

Ortega, St. Johns River

A little further down the river and slightly more current than Rudder. Same tannic water, same north-flowing ebb, a shade more bite. The southeasterly is the everyday summer breeze; the northwesterly arrives with a winter front and turns the day into a survival exercise.

Winds: SE 130° · NNW 330° · ENE 65°.

Course: windward-leeward with a gate.

St. Augustine Yacht Club

Matanzas Bay and the Atlantic

The hard one. Estuarine water in the shadow of the Bridge of Lions, and by far the strongest current of the four — strong enough that the leeward mark had to become a gate, because a single mark was genuinely unroundable in that ebb. Get the current wrong here and you will not finish.

Three areas: the Bay Race in Matanzas Bay, Ocean Practice outside the inlet, and an Ocean Race in the open Atlantic. Offshore racing here is real — St. Augustine Race Week runs a dedicated Atlantic offshore division.

Winds: ESE 120° · NE 40° · SSW 190°.

Current: ebb sets north, flood south.

Palm Beach Sailing Club

Lake Worth Lagoon, West Palm Beach

My first club — which is why it's here, even though everything else is north-east Florida.

Clear blue coastal water and the lightest current of the four. The lagoon runs north–south and racing happens east of the Intracoastal channel — beside the shipping water, not in it. The default is a soft seven-knot summer southerly; a winter front swings it northwest at sixteen and changes the venue completely.

Three areas: the Lagoon Race, Inlet Practice near Peanut Island, and an offshore Ocean Race out through the Lake Worth Inlet, where the real easterly Atlantic sea breeze fills in.

Winds: S 175° at 7 kn (default) · NW 330° at 16 · E sea breeze offshore.

Current: ebb sets north toward the inlet, flood south.