Navigation

1 Where it is, and what is in it

Navigation sits in the top navigation bar between Boats and Import. Everything to the right of it is a record of sailing that has already happened; everything at or before it is the boat and the intention.

Six tabs:

• Plans — every race plan every boat in the organisation holds, grouped by boat.
• Weather — the forecast files the platform has already built for one boat’s routed plans, whether each one still covers the route, and a viewer that draws one on the chart.
• Routing — computing a route from a plan, a polar and a forecast, in your browser. See section 10.
• Marks — positions the organisation reuses, on a chart and in a table.
• Notes — the plans that carry a navigator’s log, and the opening of what it says.
• Handicap — corrected time from a rating and an elapsed time. A calculator, not a scoring system.

Nothing moved. A plan still belongs to one boat, still opens in the same editor, and the boat’s own list at Boats → Race plans is still there and still works. Links and bookmarks you already hold keep working. This section is a second way in, not a replacement.

2 Plans: the whole fleet in one list

The Plans tab is the section’s front page. It reads every boat’s plan library and lists them under the boat’s name, in the order the fleet is listed on Boats. Two orderings are offered inside each boat: Recently updated (the default — the plan somebody touched last is the plan somebody is about to sail) and Name.

Each row carries what the plan holds, as small chips:

Clicking a plan’s name opens the boat’s own editor — the map, the waypoint list, the zones, the notes. Everything the Race plans guide describes applies unchanged.

New plan asks for the boat first, because a plan belongs to a boat and this is the one screen where that is not already decided. Pick the boat, name the plan, choose the type, and the editor opens on a map.

If one boat’s plans cannot be read, that boat says so. A failed read shows the failure under that boat’s name, and never as an empty list. “No plans” is a statement a navigator acts on, so it must never be a network error shown as an empty result. The other boats are unaffected.

Deleting a plan is done from the boat’s own list, not from here. Removing something is safer on the page that shows you what it sits among.

3 Taking a plan away: GPX export

Export GPX appears on every row of the library and beside Save plan in the editor. It downloads the plan as a GPX 1.1 route — one <rte> with every waypoint in order, each with its name.

• The editor exports what is on screen, unsaved edits included. A file is not a save; you asked for the plan you are looking at.
• Re-importing your own export into Nordic Stars gives back the positions, the names and the order. The rounding sides and passing radii come back at their defaults, because the GPX importer reads waypoints and not extensions — the same thing a plotter sees.
• A plan with no waypoints cannot be exported, and the button says so rather than handing you an empty file.
• No recorded track is ever written. A track is where a boat went; a plan is a course to sail. Nordic Stars refuses to read one on import and does not write one on export.

Importing a committee’s GPX into a plan is the other direction and is covered in Race plans.

4 Weather: what has already been fetched

The Weather tab shows one boat at a time — pick the boat at the top. The choice is in the address bar, so the page is a link you can send. For each of that boat’s plans it lists the corridor bundles the platform holds: one packed file per weather model run, clipped to a corridor around that plan’s route, plus the sea model built for the same corridor.

What to fetch is set per boat, on Boats → Weather, and the What this boat fetches link at the top of this tab goes there. The Weather guide covers the models and the corridor margin. This tab is the other half: what came back.

Each row reads:

The list is read when you open the page, and again when you pick a different boat. It states what the platform holds at that moment. It is not a cached copy and it does not refresh on a timer, so a file built while this page is open appears after a reload.

5 Stale, expired, and what is neither

Two things can be wrong with a bundle, and they are different.

• stale corridor — the file covers a box of water the route has since left. It was built around an earlier version of this plan, and editing a route is what causes it. The correct reading is this weather does not cover your route, and the page can tell you before you spend marina wifi on the download. The next scheduled fetch builds a corridor around the route as it now stands.
• expired — the last forecast instant in the file is already in the past, so it says nothing about the sailing ahead. A newer run of the same model replaces it once fetched.

Age on its own is never called stale. A three-hour-old ECMWF run is the freshest run that exists. Marking it would be grading the model’s publishing schedule rather than telling you a fact about your race, so the ages are printed and left to you.

Each row carries two buttons and they do different things. Download hands you the packed file itself — the file the tablet reads at sea, and the one to keep for a passage with no signal. Open loads the same file into this browser and draws it: see section 6.

An empty list has three ordinary readings, and the page says which:

• A plan with no route, or a windward/leeward plan, has no corridor to clip a forecast to, and never has bundles. That is arithmetic, and the page says so beside the plan rather than showing you a blank.
• A routed plan with nothing fetched yet. The platform keeps the five most recently updated routed plans of each boat current, and the job runs every ten minutes — so a plan drawn now has its files about ten minutes later, plus the build.
• The boat’s subscription does not cover it. Building bundles costs the platform compute and bandwidth on a schedule, so it is done for covered boats. The plans themselves are never behind that gate — you keep reading, drawing and exporting them either way — and the page names the reason and links to billing rather than pretending there is no weather.

6 Weather viewer: the forecast on the chart

Open on a forecast row loads that file into your browser and draws it over the plan. The forecast is drawn in your browser, by the same code the tablet runs at sea — the routing engine and the file decoders are one program, compiled to run in both places, so a wind speed read here and the same wind speed read on the boat are the same number.

The map shows, from the bottom up:

• Wind speed, as a coloured wash with a scale under the map. The scale states the lowest and highest speed on screen, so it reads the water in front of you rather than a fixed range. The colour runs the way the common forecast sites run it: violet and blue for calm, green and yellow through the middle, orange and red for strong wind, with fixed steps at 5, 10, 15, 20, 25, 30 and 40 knots.
• The sea model, when the platform has built one for this plan: land, the coastline, and yellow over water shallower than this plan’s draft plus its safety margin. Seamarks are drawn where the file carries them. The wind wash stops at the shoreline wherever this file carries one: wind is a fact about water, and a forecast corridor is a rectangle around your route rather than a coastline. A plan with no sea model has no land to stop at, so there the corridor edge is the only limit. Water the forecast says nothing about is left blank as well — blank water is a gap in the model or land, and never a calm.
• Gust and pressure contours, when the file carries those variables. Not every model packs them.
• Current arrows, when the file carries a current field. An arrow points where the water is going, which is the opposite convention to a wind barb. Currents and tides covers where the current comes from and what it changes.
• Wind barbs, on a spaced grid. They thin out as you zoom out so they never overlap.
• Your plan: the route, the waypoints, the planned start and the exclusion zones, on top of everything and read-only. Nothing on this page edits a plan.

BARBS and FIELD above the map choose which of those two layers the map emphasises. BARBS is the default: the wash is drawn at 30 per cent, light enough to read the chart through. FIELD draws the same wash at 70 per cent and doubles the spacing between the barbs, so wind speed is readable across the whole corridor and the barbs still give the direction. Both settings read the same file, the same colour scale and the same sample grid — only the opacity and the barb spacing change, so a speed read in one is the speed read in the other. The setting is stored in this browser and applies to every plan you open.

How to read a barb

A barb points at the direction the wind comes from. The shaft runs from the position out towards the weather, and the feathers on it add up to the speed:

• Half a feather is 5 knots. There is never more than one, and it sits closest to the position.
• A full feather is 10 knots.
• A filled triangle is 50 knots, drawn at the far end of the shaft.
• A circle means the wind is under 2.5 knots.

A barb is rounded to the nearest 5 knots, because that is the alphabet it has. The exact speed is in the colour under it, in the scale, and in the chart you get by clicking the map.

Time, and models

The slider under the map walks the steps the file itself carries, not an hour axis of ours: a model that packs hourly steps for the first day and three-hourly steps after it moves in exactly those jumps. The arrows step one at a time and Play runs at one step a second. The label states the instant in UTC and how far it is from the model run.

When the platform holds more than one model for this plan, each is a button above the map, newest run first. Switching model loads that file. Files stay loaded for as long as you are on the page, so switching back and forth is immediate; the panel says how many are loaded and how many megabytes they are.

This page holds up to 192 MB of files at once. A file stays in memory until it is released, and the panel prints how much is held. Over that limit the file you have drawn from least recently is released first, and the file you just opened is never the one released, however large it is. Switching back to a released file downloads and decodes it again. Leaving the page releases everything.

Clicking the map

A click asks two questions about that point. The first is the weather over the whole run — wind speed, wind direction, gusts and pressure where the file carries them — drawn as a chart under the map. A gap in a line is a step the file says nothing about at that point, which is not the same as a calm and is never drawn as one.

The second is the depth, when a sea model is loaded: the sounding, the survey it came from, the resolution of that survey and the vertical datum. A 30 m sounding from a 115 m grid and a 30 m sounding from a cell a kilometre across are the same number and different facts, and the card tells you which one you have.

A forecast file is one model run, and it does not replace the judgement of the crew on board or the official forecast for the area. What is drawn here is what that run said when the platform fetched it. The map under it is a coastline for planning and the sea model is a planning aid, not a chart: the plotter on board stays the authority.

If a file will not open, the page says so and offers two ways on: the same row’s Download button, and a file picker that reads a file already on your computer. The picker uploads nothing — the file is read in your browser, by the same decoder.

7 Marks: positions you reuse

A mark is a named position the organisation keeps: a buoy, a race mark, either end of a gate, a headland, a light, a hazard. They belong to the organisation and not to a boat — a headland is a fact about a coast — so a two-boat programme racing the same water keeps one list instead of two.

The tab shows them on a chart and in a table together: clicking a dot selects its row. Search filters by name, note or kind. Any role reads; adding, editing and archiving takes an organisation member or above — the same bar as a race plan, and for the same reason: the person who has just been out there and fixed a buoy’s real position is very often not an admin.

Positions are typed in degrees and decimal minutes, the one spelling this product uses, so a position read off this screen is the position dialled into the tablet. Notes are short by design — 280 characters — because a note here is read in a picker beside nineteen others.

The Source column

Each row records where its position came from: Typed, From GPX when it arrived in an imported file, or From a plan when it was taken from a race plan’s waypoints. It is set when the mark is created. The edit form prints it under the fields and does not let you change it.

The column is there because those are different claims about the same buoy. A position off a race committee’s file is where the committee said the mark would be; a position taken at a rounding is where somebody found it. They deserve different confidence, and the Source column is the only place that difference is recorded. Nothing on the platform reads it: no position is graded, weighted or preferred because of what it says.

Putting a mark into a plan

Open a plan and use Add from marks above the waypoint list. The waypoint arrives with the mark’s name and position, the usual 50 m passing radius and the usual rounding side — which side to leave it is a fact about this race, not about the mark, so it is never guessed from the mark’s kind. A waypoint taken this way carries a small from a mark chip.

Archiving, and why there is no delete

• Archiving is how a mark is disposed of. It leaves every picker, plans that used it keep their own positions and keep working, and it stays in the list so it can be brought back.
• Archiving frees the name. That is what makes it safe — a name that simply disappeared could be created again meaning something else, and next season’s “Hurst Castle” would quietly answer for last season’s. The cost is that bringing a mark back can fail: if something else has taken the name meanwhile, the app says so and one of the two has to be renamed.
• Names are unique among live marks. A picker with two “Hurst Castle” rows is a picker somebody picks wrong from.

Importing a committee’s GPX

Drop the file in and every position it holds — routes and loose waypoints alike — becomes a candidate. A marks list has no order, so unlike a plan’s import there is no route to choose. Before anything is created the preview says exactly what it will cost:

• positions with no name are numbered Mark 1, Mark 2 …;
• names longer than 40 characters are cut, and counted;
• a name a live mark already holds is skipped, not renamed — inventing “Hurst Castle (2)” would put a name nobody chose into the picker.

Nothing on the platform computes from a mark. No distance is measured, no position checked against a coastline, no duplicate found for you. The navigation happens on the boat.

8 The navigator’s log, and routes pinned from the boat

A race plan carries two pieces of writing and one piece of computed output. Notes is the plan: what you intend before the start. The navigator’s log is the record of sailing it. A pinned route is the answer the routing engine gave on the boat.

The navigator’s log

The log is a text box on the plan editor, under Notes. It holds up to 8192 characters and the counter under the box shows how many are used. It is saved with the plan, by the same Save button.

• It replaces whole and does not append. Saving writes the contents of the box over whatever is stored. If the boat has added a line since you opened the page, your save replaces that line.
• Both ends can write it. The tablet writes the log at sea and this page writes it ashore. Two people writing at once means one of the two versions is lost, which is what the conflict prompt below exists to catch.
• Emptying the box clears the log. There is no separate delete.

When the plan changed while you were editing it

Saving a plan that somebody else has changed since you opened it is refused, and nothing is written. The panel offers two answers: Discard mine, load theirs and Overwrite theirs with mine. There is no merge.

The refusal now names two times: when your edit was made, and when the stored plan was last saved. Both are absolute times, not “2 hours ago”. This matters offline: an edit made at sea at 14:02 may not reach the platform until 15:40, and the two times are how a crew tells which version is newer.

The time of your edit is sent with the save and is not stored. It is used to write that message and then discarded.

Pinned routes

A pinned route is a routing computed on the boat and attached to a plan. The plan editor does not route: it reads what the tablet pinned. If no route has been pinned, the plan says No pinned route from the tablet yet. To compute a route in the browser, use the Routing tab (section 10), which does not write a pin.

A pin shows:

• Model — which forecast the routing was computed against, as the tablet names it. It is shown exactly as stored.
• Computed — when the engine produced the answer, and how old that is. This is the age that matters.
• Pinned — when it was saved, and from which device. This is usually a few minutes after it was computed.
• Finishes — the ETA at the end of the route.
• One card per leg — the waypoint it ends at, the board, the heading in degrees true, the forecast wind angle and speed, and the ETA at that waypoint.

On the map the pin is drawn as a thin dashed line joining the plan’s waypoints in the order the pinned route visits them. The pin stores a summary of each leg and not the routed path, so the shape of the line between two marks is the plan’s straight line, not the course the engine computed.

Nothing expires or recomputes a pin. Editing the plan does not clear it and does not update it. If the plan was saved after the routing was computed, the page says so and prints both times; it does not decide whether the change matters. A pin may also point at waypoints the plan no longer has — those legs are listed but not drawn.

A pin does not have to cover the whole course

A pin may hold fewer legs than the plan has waypoints, and may start anywhere in the route. A routing computed on the boat from where the boat is, into a course already partly sailed, is the ordinary case rather than a fault. Nothing on the page treats a short pin as an error, and the legs it does hold are read the same way as any other.

A pin carrying no legs at all is also valid. What it holds then is the model it was computed against and the finish time, which is what a routing with nothing left to summarise produces. The panel says so in place of an empty table.

Pinned routes also appear on the Plans tab, one line per plan, which opens to the same panel. They load after the plans, one request each.

9 Deck channels: putting numbers on the instrument displays

Deck channels is what Race Control transmits to a boat’s own instrument bus, so the crew reads these numbers on the mast and cockpit displays instead of on the tablet. It is a boat setting: open it from Boats, or from the boat’s heading on the Plans tab.

The gateway

The gateway is the hardware between the tablet and the instrument bus. Choose the kind, then give its address and port on the boat’s network. Four kinds are supported: Yacht Devices RAW over UDP or TCP, Pixel sur Mer Exocet over UDP, and FaRo XDR over UDP.

• No gateway is a normal state. Slots can be configured before the hardware is installed. Nothing is transmitted until a gateway is set.
• The gateway must be set bi-directional on the device itself. Yacht Devices gateways ship in listen-only mode. A listen-only gateway accepts this configuration and transmits nothing.
• The address is not validated. The platform cannot reach the boat’s network. Ports have no default, because the default port differs between gateways and between firmware versions.

Slots

A slot is one number on one display field. A boat holds at most 64. Each slot carries:

• Transport — B&G over NMEA 2000, Expedition protocol over UDP, FaRo XDR, or Garmin over NMEA 2000.
• Key — what addresses the field on that transport. For B&G this is the key number, and the picker lists the keys identified for the race timer, targets, laylines, opposite tack, the start line, Remote 0–9 and User 1–32. Any number can be typed in directly.
• Value — either a channel the platform records, or one of the numbers the tablet computes on deck: time to gun, time to burn, distance to line, line bias, layline times and distances, opposite tack heading, target boat speed and TWA, polar boat speed and VMC.
• Two labels — 8 characters and 16, because the displays impose those limits. A longer label is truncated by the instrument without warning.
• Decimals, damping and rate — 0 to 4 decimals or Auto; damping 0 to 30 seconds; rate 0.5 to 5 Hz.

Damping here is separate from the damping the boat’s own processor applies, and the two add up. A value damped 6 s here and 6 s again by the instrument lags by 12 s. Use 0 for countdown values.

A slot on a channel your organisation has archived keeps transmitting. It is saved back unchanged, so archiving a channel never blanks a display that is already in use. The slot says so under its Value picker, and the archived channel cannot be picked for a new slot.

Two presets fill the slots for you: the B&G race set (eight slots — timer and burn undamped, targets and polar damped, laylines and opposite tack) and the start set (four slots: time to gun, time to burn, distance to line, line bias). A preset replaces the slots on screen and is not itself stored.

The start set puts distance to line on User 1 and line bias on User 2, and the reason is worth knowing before you move them. Time to gun and time to burn have B&G keys of their own. For those other two, no standard key is published, so they have to go on some field — and a User field is one nothing else on the bus writes, so putting them there cannot collide with a number an instrument processor is already sending.

H5000 emulation

Claiming an H5000 CPU source address unlocks display pages a Triton2 does not otherwise show. On a bus that already carries a real H5000 this is an address collision, and it can take instruments off the network during a race. The platform cannot see the bus: it stores the setting and serves it back. The tablet performs the check and declines the claim if it detects a real H5000. Off is the default.

Saving

Last save wins. The tablet can edit the same document. There is no conflict prompt on this page: the last save is what the boat transmits. To undo a lost edit, save the previous configuration again.

What is not verified

Three limits are worth stating plainly.

• Garmin slots transmit nothing. The NMEA 2000 message that carries Garmin custom data has not been identified. The transport is in the list so the document can describe a Garmin boat. Slots on it are stored and nothing is sent for them.
• Display verification is pending. No configuration on this page has been checked against a physical display. The B&G key names are our best identification of each key; none has been confirmed on an instrument.
• Bus load is not calculated here. The platform has no connection to the instrument system. Two slots may share a key: that is stored, not refused, and which one the display shows is decided on the boat.

10 Routing: a route computed in your browser

Navigation → Routing computes a route from a race plan, the boat’s polar and one weather file the platform has already fetched. It uses the same routing engine the tablet runs at sea, compiled to run in the browser, so a route computed here and the same route computed on the boat return the same numbers.

Pick a boat, then press Route this plan on a plan.

What it needs

• A route. The plan must hold waypoints. A windward/leeward plan and a plan with no waypoints cannot be routed, and the list says which.
• A nav polar. The boat needs one under Boats → Polar, on the Nav tab. There is no default polar: with none, the page says so and computes nothing.
• A weather file. One of the corridor bundles listed on the Weather tab. If the platform holds none for this plan, there is no wind to route against.
• A start time, which you type. It is read as UTC and the field says so. Outside the forecast file’s own time range the calculation runs out of weather and reports how far it got.

The route starts at the plan’s start position when it has one, and sails every waypoint in order. A start position is one approximate position, not a measured start line, so the first leg is as accurate as that position is. With no start position the route starts at the first waypoint and sails the rest; the page prints which of the two it used.

What it draws and what it reports

The violet line is the routed path. White dots are turning points, where the path changes board. A violet dot with a white ring is a sail change, labelled with the sail the boat’s crossover chart calls for from that point on. The grey lines are isochrones: how far the boat could have reached by each step of the calculation. The sea model, when the platform holds one for this plan, is drawn under the course as it is in the weather viewer, and a route pinned from the tablet is drawn as the same thin dashed line the plan editor uses.

The tables under the map give:

• ETA and elapsed time for the whole route, and per leg.
• Distance sailed — the distance along the routed path, not the straight-line distance between marks.
• Manoeuvres — how many times the path changes board.
• Time on each board, as a duration and a percentage.
• Wind along the route — one row per board, with the wind angle, wind speed and boat speed the engine used, averaged over the board by time, and the sail the crossover chart calls for on that board.
• Sail changes — how many each leg asks for, and each one listed as a time and the pair it changes between.

The crossover chart is the boat’s own. Each sail carries the wind speeds and angles it is declared for, set on the boat’s Sails page or on the tablet aboard, and both surfaces read the same ranges. Nothing measures them — they are what the crew entered. The page says which chart the answer was routed on.

A boat that has declared no ranges still gets a sail column: the chart is seeded from each sail’s category, which is an ordinary shape of use rather than a measurement, and the page says so and points at the page that fixes it. The two are never mixed — one declared sail makes the whole chart the boat’s. A boat with no sails registered gets no sail column at all.

Depth is checked against the boat’s draft plus the plan’s safety margin, using the sea model. With no sea model nothing checks the depth, and the page says so. With no safety margin the check uses the draft alone.

When a leg does not arrive

Every leg row carries an outcome, in the engine’s own four words:

When the first leg finds no way through and sails no board at all, the route never left the start position, and the page says why rather than leaving the word on its own. It probes the sea model at the origin once and prints what it found — the depth there, the boat’s draft and the plan’s margin — or names the position as land when the depth is negative. With no sea model loaded the depth was never checked at all, so the page says the only constraint left that can refuse every heading is an exclusion zone.

A route with no depth samples has not lost its sea model. Depth is sampled along the legs a route completes, so a route where no leg arrived reports none — and the page says the sea model is loaded and the check was applied. The absence is about the route, not about the file. The same rule governs the isochrones: a route that finished inside one step of the calculation draws none, and so does a route that stopped before a step was recorded, and those are two different sentences.

Sensitivity: routing the same course several ways

A single route is one answer to one set of assumptions. The sensitivity panel computes variants of the same course and puts them in one table with the baseline, each row showing its ETA, its difference from the baseline, its distance and its number of manoeuvres. Click a row to draw that variant on the map, with the baseline dashed underneath it.

Three things can be varied:

• Polar scale (%) — a percentage of every target speed in the polar. 95 routes a boat five per cent slower everywhere. Use it to see how much of the ETA rests on sailing the polar exactly.
• Start offset (minutes) — the same course started earlier or later. The forecast does not change; the boat meets a different part of it.
• Forecast model — the same course against another weather file the platform holds for this plan. This is how two models are compared.

Enter percentages and offsets as numbers separated by commas. One calculation runs at a time, so variants are computed one after another, and at most 8 run in a batch. A longer list is cut and the page says how many were left out.

What is not available

Three variations a navigator may look for cannot be computed, and the page lists them with the reason rather than leaving them out:

• Wind speed scale. The engine reads wind from a packed forecast file and takes no wind-speed scale. Changing it would mean writing a new forecast file, which this application does not do.
• Wind direction offset. The same reason: the direction comes from the file.
• Reverse isochrones. The engine computes isochrones forward from the start and offers no backward calculation.

Adopting the route as waypoints

Adopt as waypoints writes the routed path into the plan’s route: the plan’s own waypoints in order, with the routed path’s turning points inserted between them. The confirmation names how many waypoints are being replaced and how many will replace them, split into the ones kept and the ones added.

• Turning points carry no mark. They come from the calculation, not from the marks database, so they hold no link to a mark. The plan’s own waypoints keep the marks they were taken from.
• Nothing else on the plan changes. The name, the type, the exclusion zones, the safety margin, the notes, the log and the start position are written back exactly as they were read.
• A plan holds at most 200 waypoints. If the routed path would exceed that, nothing is written and the page says so.
• It writes no pin. A pinned route is computed on the boat; this page reads one and never writes one.

A computed route is a planning result, not a passage plan. It follows the forecast in one file and the depth in one sea model, both of which can be wrong or incomplete, and the ship’s plotter stays the navigator’s authority.

11 Chart tools: measuring on the map

Every map in this section — the plan editor, the marks chart, the weather viewer and the routing map — carries the same three tools in its top-left corner. They are off until you press one: with all three off, a click on the map does what it did before, so placing a waypoint, probing the forecast and selecting a mark are unchanged.

While a tool is on, it takes the map’s clicks. Press Escape, or the tool’s own button, to switch it off; the measurement is cleared with it, and nothing is saved.

Measure

Click two points. The strip under the map reports the range in nautical miles, the bearing in degrees true, and the reciprocal — that bearing turned through 180 degrees. A third click starts a new measurement.

A range is printed to two decimals under 10 nm and to one decimal at or above it. A bearing is whole degrees, always three digits, and always marked T for true.

Dividers

Each click adds a leg from the last point. The strip lists every leg with its own range and bearing, then the total — the sum of the legs, not the distance from the first point to the last. Stepping a course out this way gives the distance sailed round it.

Range and bearing

Places a new mark at a bearing and a range from a position you choose. Click the chart to set that position, or use the mark or waypoint already selected beside the map. Type the bearing in degrees true and the range in nautical miles: the position is drawn on the chart and printed in degrees and decimal minutes before anything is sent.

Save as a mark adds it to the organisation’s marks database through the same operation the Marks tab uses. It needs member access or above, the name must be free among the live marks, and the confirmation names the position it was saved at.

• The mark records the computed position only. It keeps no link to the position it was measured from, so correcting that position later does not move this mark. That is the copying rule in section 7, applied to the tool.
• Its source reads Typed, because a person typed the bearing and the range.

The corner readout

While a tool is on, the box under the buttons reports the range and bearing from a selected position to the cursor. On the marks chart that position is the mark you have selected; on the plan editor, the weather viewer and the routing map it is the selected waypoint, or the plan’s planned start, or its first waypoint. With nothing to measure from, the box says so.

These maps draw plans and marks rather than a live position, so there is no boat to measure from here. The boat’s own range and bearing to a mark is read on the tablet.

These are planning figures. Ranges and bearings are great-circle values on a spherical earth model, computed in your browser and stored nowhere unless you save a mark. Over a long leg the reciprocal is not the same as the bearing measured back from the far end, because the meridians converge. The plotter on board stays the authority.

12 Notes: every plan that carries a log

Section 8 describes the navigator’s log and how it is written. The Notes tab is how you find one: it lists every plan in the organisation that carries a log, newest save first, with the boat’s name, when the plan was last saved, and the opening of the text.

Each row links to the plan’s editor, which is where the log is written and changed. The tab itself is read-only. It finds the log; it does not edit it, and nothing here can delete it.

A plan with no log is not listed. That is not an error — most plans do not carry one, and a list of every plan in the organisation already exists on the Plans tab.

13 Handicap calculator

Navigation → Handicap corrects an elapsed time with a rating you type in, for one boat or for a fleet of up to twenty. It also works out the time one boat gives another over a course.

The systems, and the formula each one uses

What you enter

• The rating, per boat, in whatever the chosen system calls it. A rating far outside that system’s usual range is marked in the table and still calculated — a multihull, a Mini and a classic all sit outside somebody’s idea of normal.
• The time, either as an elapsed time in H:MM:SS or as a start and a finish clock time. A finish earlier in the day than the start is read as the next day; for a race longer than 24 hours, enter the elapsed time. A bare number is refused rather than guessed — “90” is ninety seconds to one navigator and an hour and a half to another.
• The course distance in nautical miles, for a time-on-distance system. A time-on-time system does not read it.

The table

Up to twenty boats. Every column sorts, and the shortest corrected time leads by default. A boat with no rating or no readable time stays in the table with the reason printed under it, is never given a place, and never sorts above a boat that finished. Two boats on the same published second share a place, as they would on a results sheet.

The boats you type into and the sorted table are two separate tables on purpose: a table that re-sorts while you type moves the row out from under the cursor.

Time to give, time to take

Two boats, two ratings, and the time between them. What that depends on is the real difference between the two families of system:

• Time on distance — the allowance is the difference between the two ratings multiplied by the course length. It is fixed before the start.
• Time on time — the allowance depends on how long the race takes, not on how long it is, so this needs an expected elapsed time and is not settled until a boat finishes.

Everything you type stays in this browser. Nothing is sent to the platform, nothing is written to a plan, and another person opening the page sees their own numbers. Clearing the browser’s storage clears the calculator.

14 Where to go next

• Race plans — drawing a route on the map, exact positions in degrees and decimal minutes, exclusion zones, and importing the committee’s GPX.
• Weather — choosing what the platform fetches for a boat, the models and the limit each one carries, and the corridor margin.
• Race Control on the boat — loading a plan on the tablet and sailing it.