Avelsta Guide Online NKE reader Open Avelsta

Speed polars

Free polar generator, no account needed

BeginnerUpdated

Compute your sailboat’s polar for free from your NKE logs, without creating an account: upload the files, choose the sessions, STW or SOG, polar completed from references.

The essentials

Avelsta’s Polar Generator computes a polar from your logs, with no account and no email.

  1. Open Polar Generator.
  2. Drop your .LOG (NKE Box WiFi) or .nkz (NKE Processor HR) files, 200 MB at most per upload.
  3. Wait until your sessions are ready; they are all selected as source sessions.
  4. Choose the speed: STW (through water) or SOG (over ground).
  5. Click Generate automatically: the polar is shown, with the share of measured cells and the reference polars used to fill in the rest.
The polar generator, before uploading logs
Polar Generator: drop your logs

Going further

Computation steps

Step What happens
Reading the sessions Sailing points of each selected session
TWS / TWA binning Grouping into angle (10°) and wind (2-knot) cells; 95th percentile of the speeds in each cell
Completion from references Empty cells filled from the closest reference polars
Result Complete, smoothed polar, shown as a diagram and a table

The method is the same as with an account: see Generate a polar from your sessions.

Polar generated without an account
The polar computed from the uploaded logs

Choosing the sessions

Untick a session to leave it out of the computation (delivery trip, engine, unusual conditions), then click Generate automatically again. Select all / Unselect all to go faster, + Add logs to upload more files, and a session’s cross to delete it from the trial.

Keeping the polar

Without an account, the polar is not saved: it disappears when the tab is closed, and the logs are deleted after 6 hours. Click Create an account to keep it: your trial sessions move to the account, where you will generate and save the polar.

Replaying with this polar

Replay a session with this polar opens the replay, comparing the boat speed with the polar just computed.

Frequently asked questions

Is the generator really free?

Yes, with no account and no credit card.

Can I download the generated polar?

Not yet: create an account to save it and use it in Avelsta.

See also

  • Try Avelsta without an accountUpload your NKE logs without creating an account: replay and generated polar in a few minutes. Trial duration (6 hours), limits, and how to keep your sessions by creating an account.
  • Generate a polar from your sessionsCompute your sailboat’s measured polar from your NKE logs: choice of sessions, STW or SOG, measured cells, completion with similar reference polars, saving.
  • What is a boat speed polar?A sailboat’s speed polar gives the target speed for each true wind angle and true wind speed (TWA, TWS). Reading the diagram and the table, theoretical polar and measured polar.
  • Explore the example sessionDiscover Avelsta without your own logs with a real 23-hour example session, read-only, compared with its boat’s polar.