Ellipsoid: Clarke 1866
Prime meridian: Greenwich
Data source: EPSG
Information source: http://www.ngs.noaa.gov/ (NADCON readme file).
Revision date: 2022-12-12
Scope: Topographic mapping.
Remarks: Hawaiian Islands were never on NAD27 but rather on Old Hawaiian Datum. NADCON conversion program provides transformation from Old Hawaiian Datum to NAD83 (original 1986 realization) but making the transformation appear to user as if from NAD27.
Area of use: United States (USA) - Hawaii - main islands onshore.
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json", "type": "GeodeticReferenceFrame", "name": "Old Hawaiian", "ellipsoid": { "name": "Clarke 1866", "semi_major_axis": 6378206.4, "semi_minor_axis": 6356583.8 }, "scope": "Topographic mapping.", "area": "United States (USA) - Hawaii - main islands onshore.", "bbox": { "south_latitude": 18.87, "west_longitude": -160.3, "north_latitude": 22.29, "east_longitude": -154.74 }, "id": { "authority": "EPSG", "code": 6135 } }