Last updated 26 August 2026
Quartet is provided as is, with no warranty of any kind. Its output is an automated estimate that you must independently verify before relying on it, publishing it, or acting on it. If you do not agree to these terms, do not use Quartet.
Quartet ("the Service") is a personal, non-commercial project that searches public satellite imagery for possible aircraft and cross-references public flight data. It is made available to a limited group of invited testers for evaluation and feedback. By accessing or using the Service you agree to these Terms of Use and to the Privacy note. If you are using Quartet on behalf of an organization, you represent that you are authorized to accept these terms on its behalf.
The Service is under active development and provided for testing and evaluation. It is provided "as is" and "as available," without warranties or conditions of any kind, whether express, implied, or statutory — including, to the maximum extent permitted by applicable law, any implied warranties of merchantability, fitness for a particular purpose, accuracy, reliability, availability, title, and non-infringement. The operator does not warrant that the Service will be uninterrupted, timely, secure, error-free, or that any defect will be corrected. You use the Service at your own risk.
This is the most important thing to understand about Quartet:
You are solely responsible for independently verifying any output through primary sources before relying on it, republishing it, attributing it to any person or aircraft, or making any decision based on it. Do not present Quartet's output as established fact.
Quartet's output is provided for research and informational purposes only. It is not legal, journalistic, investigative, intelligence, navigational, or other professional advice, and it is not fit for navigation, air-traffic, safety-of-life, security, or any operational or real-time decision-making. Do not use it for any such purpose.
You agree that you will not, and will not attempt to:
The Service may not be used by anyone under the age of majority in their jurisdiction, or by anyone barred from receiving it under applicable law.
Quartet's output is derived from data supplied by third parties (including ESA / Copernicus Sentinel-2 imagery and adsb.lol flight data) under those parties' own licenses. The operator grants you no rights in that underlying data beyond your own permitted use of the Service. If you export, republish, or distribute Quartet's output, you are responsible for complying with the applicable third-party terms and for carrying the required notices, including, where the output contains modified Copernicus Sentinel data, a notice in the form "Contains modified Copernicus Sentinel data [year]", and, where it contains adsb.lol data, the attribution and share-alike terms of the Open Database License (ODbL). See the Privacy note for the list of data sources.
Access is by invitation and is tied to the email address you sign in with. You are responsible for keeping access to that email secure and for all activity that occurs under your account. Tell support@quartetsearch.com promptly if you believe your access has been used without your permission.
The Service is offered on a best-effort basis with no guarantee of availability, and it may be changed, suspended, limited, or discontinued at any time, in whole or in part, without notice or liability. Because access is by invitation for testing, the operator may suspend or revoke your access at any time, for any reason or no reason. You may stop using the Service at any time.
To the maximum extent permitted by applicable law, in no event will the operator be liable for any indirect, incidental, special, consequential, exemplary, or punitive damages, or for any loss of profits, data, goodwill, or reputation, or for any damages whatsoever arising out of or relating to your use of, or inability to use, the Service or its output — including any decision made, action taken, or content published in reliance on the output — whether based in contract, tort (including negligence), strict liability, or any other theory, and whether or not the operator has been advised of the possibility of such damages.
To the maximum extent permitted by applicable law, the operator's total aggregate liability for all claims relating to the Service will not exceed the total amount you paid to use the Service. Because some jurisdictions do not allow certain exclusions or limitations of liability, parts of this section may not apply to you; where a limitation in these terms is not enforceable, the operator's liability is limited to the smallest extent permitted by applicable law.
To the extent permitted by applicable law, you agree to indemnify and hold harmless the operator from any claims, losses, liabilities, and expenses (including reasonable legal fees) arising out of your use of the Service, your export or publication of its output, or your breach of these terms.
These terms, and any dispute arising out of or relating to them or to the Service, are governed by the laws of the United States and of the state in which the operator resides, without regard to conflict-of-laws principles, and you agree to the exclusive jurisdiction of the state and federal courts located there. Nothing in these terms limits any right you may have that cannot be limited under the law that applies to you.
These terms may be updated as the Service develops; the "last updated" date above will change when they do. Continued use of the Service after an update means you accept the revised terms.
Questions about these terms? Email support@quartetsearch.com, or see the contact page.
Quartet is an independent personal project provided as-is. These terms govern its use during the current testing phase.