# CRS documentation — KTEB airport vector map

**Delivered CRS: WGS84 geographic (EPSG:4326).** All GeoJSON layers and the GeoPackage
are in EPSG:4326 (GeoJSON per RFC 7946 is CRS84, i.e. WGS84 lon/lat order), which is what
an EFB GPS overlay consumes directly.

**Working / measurement CRS: UTM zone 18N (EPSG:32618).** Teterboro sits at 74.06 W,
inside UTM 18N. All metric operations (taxiway width buffers, offset QA, the SVG export)
are performed in EPSG:32618 and reprojected back. The New Jersey State Plane alternative
is EPSG:3424 (NAD83 / New Jersey ft-US) if the client's engineering drawings use it.

**Datum note.** FAA NASR coordinates are NAD83; at this scale NAD83 and WGS84 differ by
under ~1.5 m (and under ~5 cm with epoch-matched realizations), well inside the accuracy
envelope of this pilot. Production against ADIP survey data states the realization explicitly.

Vertical: NASR field elevations are in feet MSL (NAVD88). KTEB field elevation 8.3 ft.