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Orthodrome sources & terms

Updated 2 October 2026

Sources, licences and terms of use

The data, map data and libraries Orthodrome uses are listed below with their sources and licences. The service is free to use and offered as is. It is not a tool for navigation or flight operations.

Feedback

Feedback and suggestions

Send feedback, bug reports and feature suggestions to Orthodrome on Bluesky: @orthodro.me.

Orthodrome is a personal project with no support desk, so there is no guaranteed response time.

Data

Airport data

airportsdata

ICAO and IATA codes, airport names, cities, countries and coordinates. Orthodrome uses a pinned snapshot of the dataset and does not query aeronautical authorities.

MIT
Copyright
© 2020– Mike Borsetti
Includes
mwgg/Airports, © 2014 mwgg (MIT)
Notice
Copies or substantial portions of the dataset must keep the copyright and MIT permission notice.

Wikidata

Annual passenger numbers, used to rank airports by size: larger airports come first in search, and the busiest are drawn as Major airports. Orthodrome ships a snapshot and does not query Wikidata while you use the map.

CC0

OurAirports

Airport type and scheduled service, used for the size ranking where no passenger number is available. Orthodrome uses a pinned snapshot.

Public domain

Data

Wind data

NCEP–NCAR Reanalysis 1

Monthly long-term mean winds for 1991–2020 on a 2.5° grid, used to draw wind-corrected range circles. Orthodrome ships a preprocessed snapshot of six pressure levels, with the annual mean derived from the twelve monthly fields, and does not query a weather service while you use the map.

Public domain
Provided by
NOAA PSL, Boulder, Colorado, USA, from their website at psl.noaa.gov
Reference
Kalnay et al., The NCEP/NCAR 40-year reanalysis project, Bull. Amer. Meteor. Soc., 77, 437–470, 1996
Note
A mean-wind contour describes a flight through average conditions, not a forecast and not the average of real days.

Data

Aircraft data

Aircraft families

Typical cruise speeds, cruise altitudes and per-Leg allowances for taxi, climb and descent, used for time estimates, time-based ranges and wind correction. Compiled for Orthodrome from public type data; the values are approximate, not manufacturer figures.

Orthodrome

Basemap

Map, countries and labels

World Atlas 2.0.2

Natural Earth 1:50m and 1:110m country and land outlines for the Equal Earth map, packaged with Orthodrome and drawn in your browser. © Michael Bostock; the underlying Natural Earth data is public domain.

ISC

Software

Libraries and fonts

Vue and Nuxt UI

Vue 3.5.43 and Nuxt UI 4.11.1 power the interface, built with Vite 8.3.0 and Tailwind CSS 4.3.3. Package versions and original licence notices are included with this site.

Package notices

IBM Plex

Interface typography. © 2017 IBM Corp., Reserved Font Name “Plex”; self-hosted.

OFL 1.1

mp4-muxer 5.2.2

Packs shared videos into MP4 files in your browser. © Vanilagy; self-hosted and loaded only when you export a video.

MIT

Lucide icons

Local SVG icons from @iconify-json/lucide 1.2.135. © Lucide Contributors; includes Feather portions by Cole Bemis.

ISC / MIT notices

Bootstrap Icons

Bluesky and X icons from Bootstrap Icons 1.13.1. © 2019–2024 The Bootstrap Authors.

MIT

Licence notices apply when the corresponding files or data are copied or redistributed. Using Orthodrome in a browser requires nothing from you.

Terms of use · Updated 2 October 2026

Free to use, as is, not for operations

  1. 1. Free to use

    Orthodrome is provided free of charge by Olli Vainio for personal, educational and exploratory use. No account or payment is required.

  2. 2. No operational use

    Distances, path lines and time estimates are simplified calculations over a reference dataset that may be incomplete, outdated or wrong. They ignore current weather, procedures, airspace and real dispatch planning; wind modes use long-term mean winds only. Orthodrome must not be used for navigation, flight planning, operational or safety-critical purposes.

  3. 3. No warranty

    The service and its content are provided “as is” and “as available”, without warranty of any kind, express or implied, including accuracy, completeness, availability, fitness for a particular purpose and non-infringement.

  4. 4. No liability

    To the fullest extent permitted by law, Olli Vainio and the contributors are not liable for any direct, indirect or consequential loss or damage arising from the use of, reliance on, or inability to use the service or its content.

  5. 5. Availability

    The service may be changed, interrupted or withdrawn at any time without notice.

  6. 6. Third-party content

    Datasets, map data, fonts and libraries remain subject to the licences listed above. If you redistribute any of them, keep the respective notices.

  7. 7. Changes

    These terms may be updated. The date at the start of these terms tells which version applies.

AI transparency

AI-generated content

Parts of this service, including source code, interface text and this page, were produced with the assistance of generative AI systems and reviewed by a human before publication. This notice follows the transparency obligations of Regulation (EU) 2024/1689 (the AI Act), Article 50.

Airport data, map data and path calculations are not AI-generated; their sources are listed above.