Use your ORC certificate

An ORC certificate gives you a VPP polar produced by a rating authority rather than by optimism, which is the better basis for a route.

Finding it

In the 2 · Boat panel, type into Search by boat name, sail number, or type. Search by sail number first. It is the most reliable key: boat names are duplicated across fleets and get re-registered, sail numbers are close to unique within a country.

If the sail number returns nothing, try the boat name. Certificates are indexed by the name as issued, which is not always the name on the transom.

When it is not there

Certificate data is refreshed on a schedule, so one issued in the last few days may not have been pulled yet.

Switch the source to a pasted polar in the meantime. It accepts matrix CSV, TSV and .pol files, and Expedition or PredictWind angle-speed rows, and works out which it has been given. Then tell me the sail number and the issuing authority — a certificate that should be present and is not is usually a fixable problem rather than a gap in the data.

Certificate or measured polar

A certificate polar is what the boat is rated to do. A measured polar is what it does.

Use the certificate when you want a defensible number, or when you are comparing against boats rated the same way. Use your own measurements when you know the boat is meaningfully off its rating — under-canvassed in light air, or genuinely faster downwind than the VPP believes. Routing against a polar the boat cannot hold produces a track it cannot sail.

Draft

The certificate carries a draft, which is used against the depth data to keep the route off the bottom. Check it if you have changed keels, and remember that the depth data here is generalised for planning — see the terms.