About
DRS answers one question: what was this aircraft certified to, and what did those regulations say at the time? It does this from an index that is rebuilt from source, never edited by hand.
How it is built
-
1. Source files
JSON files in the FARfetched-data repository: one per regulation provision, one per document, one per aircraft model.
-
2. Build
build.pychecks every file against its schema, then compiles them. Anything inconsistent fails the build; it never guesses. -
3. SQLite file
One read-only file,
cert_basis.sqlite, carrying a schema version so a consumer can refuse a layout it does not know. -
4. This site
Fetches the file on a schedule, verifies it, and serves it read-only. It never changes the data or re-interprets it.
The same source files always build the same index, so a mistake is fixed in the source and shows up on the next build. The footer shows the SHA-256 of the file this page is being served from.
Data source
Everything shown here comes from github.com/dekmeister/FARfetched-data. Its README is the field-level description of the data, and the build script there defines the database layout. This site contains no data of its own.
Structure of the database
The database has two halves, one for regulations and one for aircraft, joined by the certification basis.
Dashed outline: computed by the build. Solid: written in the source files.
| Part | Tables | What it holds |
|---|---|---|
| Documents | issuers, documents, document_revisions | What can be cited: each issuer's documents and every revision of them, in order. |
| Provisions | provisions, provision_versions, provision_paragraphs, version_actions | Each section and its text as it stood at every revision that touched it. Unchanged text links back to the earlier version, a deletion is marked, and a known gap is flagged rather than left blank. |
| Aircraft | manufacturers, categories, aircraft_models, tcds, tcb | Type-certificated models and their type certificate data sheets (TCDS). A certification basis belongs to a model on one TCDS. |
| Certification basis | cert_basis_entries, cert_basis_refs, cert_basis_resolved | Three layers, described below. |
| Build record | build_info | Schema version, the data repository commit and the build time. |
Three layers of a certification basis
- Entries are the lines of the TCDS, exactly as printed. They are never rewritten, and are shown beside everything derived from them.
- Refs record what each line means in a form a machine can use: which document, up to which revision, which revisions are skipped, and which provisions or paragraphs it is limited to.
- Resolved rows are the build's expansion of the refs into specific provision versions. This is what the aircraft pages display.
The site reads the resolved layer and does not interpret a TCDS line itself. If a line has been read wrongly, the fix goes into the refs in the data repository and appears on the next build.
This copy of the data
- Built
- 1 Nov 2026
- Data commit
- 6d83d086470e
- Schema version
- 3
- File SHA-256
- 41949ebef7b02dbb86ac41293385e36806ca47b69437cb0fdc7104f37d35cd52
All information is for reference only. Always check the source document.