Terms of use
Updated 14 September 2026.
Sillage is an iPhone app that keeps your logbook on your phone. It is bought once, with no subscription. These terms are deliberately simple; they will be expanded before the paid opening.
Publisher
The Sillage app (digital pilot logbook) is published by Sébastien Laus, self-employed individual, registered with the Belgian Crossroads Bank for Enterprises (Belgium) under number 0869.790.387. Contact: contact@sillage.aero — privacy: privacy@sillage.aero.
Purpose
Sillage is an EASA Part-FCL pilot logbook, as an iPhone app: record your flights and their track, have a line signed by your instructor, hand a flight from one phone to another, track your validity dates and recency, export your logbook. There is no account, no password, and no server holding your logbook.
Your logbook stays with you
Your logbook is stored on your iPhone, and backed up to YOUR iCloud account if you enabled it — the publisher has no access to it and can neither read it, restore it, nor lose it for you. The trade-off is direct: nobody but you can recover it. Export your logbook regularly and keep those copies somewhere other than the phone.
Purchase and refunds
The app is bought on Apple's App Store, as a single payment, with no subscription. Apple is the seller: payment, invoicing, refunds and the right of withdrawal fall under the App Store terms and are requested from Apple, not from the publisher. One purchase gives you the app under Apple's family sharing and purchase restoration rules.
The test phase (TestFlight)
During the test phase, the app is distributed free of charge through TestFlight to a limited number of volunteers, and they keep the app afterwards. A test version is software still being tuned: it may contain defects, change behaviour, and a build may expire. Export your logbook regularly during this period — it is the only real protection against a loss, and it stays in your hands.
What Sillage is not
Sillage is a tool, not an authority: it certifies no competence, issues no title and replaces no regulatory obligation. Reminders, calculations, gauges, proposed revalidation periods and alerts are informational, and can be wrong. Signatures collected in the app are simple electronic signatures with evidential value (art. 25 of the eIDAS regulation), not qualified: they are worth what the context in which they were given is worth.
Your responsibility
You are solely responsible for the accuracy of your logbook and for your regulatory compliance (medical, ratings, recent experience…). A logbook is a document you answer for before your authority. To the extent permitted by law, the publisher is not liable for decisions taken on the basis of the data displayed, nor for indirect damages related to the use of the app.
What the track and the import propose
The track recorder and the import of an old logbook PROPOSE values: they make mistakes, and nothing enters your logbook until you have accepted it line by line. The import reads files and printed pages, entirely on your phone; handwriting is not read. Check every line before accepting it.
Side by side
A flight, a signature request, a solo authorisation or an aircraft sheet is handed over up close, directly between two phones, without going through the publisher. What arrives is a copy, independent from the moment it is received: everyone remains responsible for what they accept into their own logbook.
The website
The sillage.aero website presents the app and collects test requests. It is provided “as is” and as available, with no guarantee of uninterrupted access. The app does not depend on it: it works without it, and without a network.
If the service ever shuts down
Your logbook depends on no server: it is on your phone, and your PDF and CSV exports open without Sillage. Should the publisher cease all activity, your logbook and your exports would remain readable and usable as they are. That is the whole point of this architecture.
Fair use
You undertake not to circumvent the app's protections, in particular the sealing of signatures, nor to present as signed a line that was not.
Governing law
These terms are governed by Belgian law; any dispute falls under the competent Belgian courts, subject to mandatory consumer-protection provisions. They may change; any substantial modification will be brought to your attention.