Attributions

Tailspot is built on the work of several open data projects, public-domain government databases, and open-source contributors. This page is the canonical credits list.

Live aircraft position data — adsb.lol

Live aircraft positions are provided by adsb.lol, a community ADS-B aggregation network.

• License: Open Database License (ODbL) 1.0
• License text: opendatacommons.org/licenses/odbl/1-0/
• Source: adsb.lol

Required ODbL attribution statement:

This product uses data from adsb.lol, which is made available under the Open Database License (ODbL) v1.0. You are free to copy, distribute, transmit, and adapt this data, provided you attribute adsb.lol and its contributors. If you alter, transform, or build upon this data, you may distribute the resulting data only under the same license. Full license text: opendatacommons.org/licenses/odbl/1-0/

Backup aircraft position data — adsb.fi

When adsb.lol is unreachable, live aircraft positions come from adsb.fi, a community ADS-B aggregation network based in Finland. Tailspot uses it for personal, non-commercial purposes under adsb.fi's open data terms.

• Source: adsb.fi
• Terms: github.com/adsbfi/opendata

Flight routes — adsb.lol route database

Origin and destination airports for scheduled flights are looked up by callsign through adsb.lol's route API, which serves the community-maintained Virtual Radar Server standing data.

• License: CC0 1.0 (public domain dedication)
• Source: github.com/vradarserver/standing-data, served via adsb.lol

Aircraft registry data — FAA Releasable Aircraft Database

Aircraft registration and identity data for US-registered aircraft (N-numbers) is sourced from the FAA Releasable Aircraft Database.

• License: Public domain
• Source: faa.gov — Releasable Aircraft Download
• Credit note: Per the FAA: "All digital products published by the FAA are in the public domain… a written release or credit is not required." This credit is provided as a courtesy.

Worldwide aircraft registry data — ADS-B Exchange

Registrations and type designators for aircraft registered outside the US come from the ADS-B Exchange basic aircraft database, which draws on government registries and community contributions. Registry details are also filled in from the live position feeds above as aircraft are seen.

• Source: adsbexchange.com

Aircraft type designators — ICAO DOC 8643

Aircraft type identification uses type designators from ICAO Document 8643 — Aircraft Type Designators, published by the International Civil Aviation Organization.

• Source: ICAO DOC 8643
• Note: DOC 8643 is a publicly accessible aeronautical reference. Type designators are factual identifiers (e.g., "B738" for the Boeing 737-800) and are not subject to creative copyright protection. This reference is used for aircraft identification, not for redistribution of the publication.

Aircraft photos — Planespotters.net

Aircraft photographs shown in the app are provided by Planespotters.net via their API. Each photograph is credited to its individual photographer as returned by the API.

• Source: planespotters.net
• Per-photo attribution: Photographer name and link are displayed alongside each photo in the app, as required by Planespotters.net's terms of use.

Aircraft type photos — Wikimedia Commons

When Planespotters.net has no photo of a specific aircraft, the back of its catch card shows a freely licensed photo of the aircraft type from Wikimedia Commons.

• Source: commons.wikimedia.org
• Licenses: Public domain, CC0, CC BY or CC BY-SA, varying by photo.
• Per-photo attribution: The author and license short name are shown under each photo in the app, and the photo and its credit link to the file's Commons page.

Aircraft type information — Wikipedia and Wikidata

The back of a catch card shows the opening sentences of the aircraft type's English Wikipedia article, unedited, with a link to the article, and facts (first flight, number built, wingspan, length) from Wikidata, bundled with the app.

• Wikipedia text license: CC BY-SA 4.0, credited in the app as "From Wikipedia · CC BY-SA 4.0"
• Wikidata license: CC0 1.0
• Source: en.wikipedia.org, wikidata.org

On-device airplane detection — YOLOX

Tailspot's visual-confirmation feature — which snaps the aiming reticle onto the detected aircraft — uses an on-device CoreML model derived from YOLOX-Small, pre-trained on the COCO dataset.

• License: Apache License 2.0
• License text: apache.org/licenses/LICENSE-2.0
• Source: YOLOX — Megvii BaseDetection
• Note: The bundled model is a weight-quantized (INT8) CoreML conversion of the stock YOLOX-S COCO checkpoint, distributed under Apache-2.0 via the pixeltable-yolox project. Weights are unmodified beyond quantization.

Typography — B612 Mono

The B612 Mono typeface is used in the app's UI.

• License: SIL Open Font License 1.1 (OFL 1.1)
• License text: openfontlicense.org
• Creator: Airbus, via the B612 project
• Source: b612-font.com

The OFL permits use, distribution, and modification of the font, provided the font is not sold by itself and derivative fonts use a different reserved font name.

Open-source software

The iOS app includes the PostHog iOS SDK for product analytics.

• License: MIT License — Copyright © 2023 PostHog
• Source: github.com/PostHog/posthog-ios

Apple trademarks

Tailspot is distributed through the App Store and displays Apple's "Download on the App Store" badge, used unmodified under Apple's Marketing Resources and Identity Guidelines.

Apple, the Apple logo, and iPhone are trademarks of Apple Inc., registered in the U.S. and other countries and regions. App Store is a service mark of Apple Inc.

Tailspot is not affiliated with, sponsored by, or endorsed by Apple Inc.