EPSG:7709

COORDINATEOPERATION["OSGB36 to ETRS89-GBR [OSNet v2009] (2)",
    VERSION["OSGB-UK Gbr15 NT"],
    SOURCECRS[
        GEOGCRS["OSGB36",
            DATUM["Ordnance Survey of Great Britain 1936",
                ELLIPSOID["Airy 1830",6377563.396,299.3249646,
                    LENGTHUNIT["metre",1]]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]],
            CS[ellipsoidal,2],
                AXIS["geodetic latitude (Lat)",north,
                    ORDER[1],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["geodetic longitude (Lon)",east,
                    ORDER[2],
                    ANGLEUNIT["degree",0.0174532925199433]],
            ID["EPSG",4277]]],
    TARGETCRS[
        GEOGCRS["ETRS89-GBR [OSNet v2009]",
            DATUM["OSNet v2009",
                ELLIPSOID["GRS 1980",6378137,298.257222101,
                    LENGTHUNIT["metre",1]],
                ANCHOREPOCH[2009.756]],
            PRIMEM["Greenwich",0,
                ANGLEUNIT["degree",0.0174532925199433]],
            CS[ellipsoidal,2],
                AXIS["geodetic latitude (Lat)",north,
                    ORDER[1],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["geodetic longitude (Lon)",east,
                    ORDER[2],
                    ANGLEUNIT["degree",0.0174532925199433]],
            ID["EPSG",11009]]],
    METHOD["NTv2",
        ID["EPSG",9615]],
    PARAMETERFILE["Latitude and longitude difference file","OSTN15_NTv2_OSGBtoETRS.gsb"],
    OPERATIONACCURACY[0.03],
    USAGE[
        SCOPE["Transformation of coordinates at 0.03m level of accuracy."],
        AREA["United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Great Britain (England, Wales and Scotland). Isle of Man onshore."],
        BBOX[49.75,-9.01,61.01,2.01]],
    ID["EPSG",7709],
    REMARK["Approximate alternative to official OSTN15 method (tfm code 7953). May be taken as approximate transformation OSGB36 to WGS 84 - see code 7710. Replaces OSGB36 to ETRS89 (1) (tfm code 5338)."]]

proj4.defs("EPSG:7709","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=uk_os_OSTN15_NTv2_OSGBtoETRS.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1");

{
    "$schema": "https://proj.org/schemas/v0.7/projjson.schema.json",
    "type": "Transformation",
    "name": "OSGB36 to ETRS89-GBR [OSNet v2009] (2)",
    "source_crs": {
        "type": "GeographicCRS",
        "name": "OSGB36",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "Ordnance Survey of Great Britain 1936",
            "ellipsoid": {
                "name": "Airy 1830",
                "semi_major_axis": 6377563.396,
                "inverse_flattening": 299.3249646
            }
        },
        "coordinate_system": {
            "subtype": "ellipsoidal",
            "axis": [
                {
                    "name": "Geodetic latitude",
                    "abbreviation": "Lat",
                    "direction": "north",
                    "unit": "degree"
                },
                {
                    "name": "Geodetic longitude",
                    "abbreviation": "Lon",
                    "direction": "east",
                    "unit": "degree"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 4277
        }
    },
    "target_crs": {
        "type": "GeographicCRS",
        "name": "ETRS89-GBR [OSNet v2009]",
        "datum": {
            "type": "GeodeticReferenceFrame",
            "name": "OSNet v2009",
            "anchor_epoch": 2009.756,
            "ellipsoid": {
                "name": "GRS 1980",
                "semi_major_axis": 6378137,
                "inverse_flattening": 298.257222101
            }
        },
        "coordinate_system": {
            "subtype": "ellipsoidal",
            "axis": [
                {
                    "name": "Geodetic latitude",
                    "abbreviation": "Lat",
                    "direction": "north",
                    "unit": "degree"
                },
                {
                    "name": "Geodetic longitude",
                    "abbreviation": "Lon",
                    "direction": "east",
                    "unit": "degree"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 11009
        },
        "remarks": "Horizontal component of second national realization of ETRS89 in Great Britain. Replaces ETRS89-GBR [OSNet v2001] from 2016."
    },
    "method": {
        "name": "NTv2",
        "id": {
            "authority": "EPSG",
            "code": 9615
        }
    },
    "parameters": [
        {
            "name": "Latitude and longitude difference file",
            "value": "OSTN15_NTv2_OSGBtoETRS.gsb",
            "id": {
                "authority": "EPSG",
                "code": 8656
            }
        }
    ],
    "accuracy": "0.03",
    "scope": "Transformation of coordinates at 0.03m level of accuracy.",
    "area": "United Kingdom (UK) - offshore to boundary of UKCS within 49°45'N to 61°N and 9°W to 2°E; onshore Great Britain (England, Wales and Scotland). Isle of Man onshore.",
    "bbox": {
        "south_latitude": 49.75,
        "west_longitude": -9.01,
        "north_latitude": 61.01,
        "east_longitude": 2.01
    },
    "id": {
        "authority": "EPSG",
        "code": 7709
    },
    "remarks": "Approximate alternative to official OSTN15 method (tfm code 7953). May be taken as approximate transformation OSGB36 to WGS 84 - see code 7710. Replaces OSGB36 to ETRS89 (1) (tfm code 5338)."
}

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	<Layer srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=uk_os_OSTN15_NTv2_OSGBtoETRS.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1">
	</Layer>
</Map>

INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 7709, 'EPSG', 7709, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +proj=hgridshift +grids=uk_os_OSTN15_NTv2_OSGBtoETRS.tif +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');