EPSG:7711

COORDINATEOPERATION["ETRS89-GBR [OSNet v2009] to ODN height (2)",
    VERSION["OS-UK Gbr 2015"],
    SOURCECRS[
        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,3],
                AXIS["geodetic latitude (Lat)",north,
                    ORDER[1],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["geodetic longitude (Lon)",east,
                    ORDER[2],
                    ANGLEUNIT["degree",0.0174532925199433]],
                AXIS["ellipsoidal height (h)",up,
                    ORDER[3],
                    LENGTHUNIT["metre",1]],
            ID["EPSG",11008]]],
    TARGETCRS[
        VERTCRS["ODN height",
            VDATUM["Ordnance Datum Newlyn"],
            CS[vertical,1],
                AXIS["gravity-related height (H)",up,
                    LENGTHUNIT["metre",1]],
            ID["EPSG",5701]]],
    METHOD["Geographic3D to GravityRelatedHeight (OSGM-GB)",
        ID["EPSG",9663]],
    PARAMETERFILE["Geoid (height correction) model file","OSTN15_OSGM15_GB.txt"],
    OPERATIONACCURACY[0.008],
    USAGE[
        SCOPE["Derivation of gravity-related heights from GNSS observations."],
        AREA["United Kingdom (UK) - Great Britain onshore - England and Wales - mainland; Scotland - mainland and Inner Hebrides."],
        BBOX[49.93,-7.06,58.71,1.8]],
    ID["EPSG",7711],
    REMARK["OSGM15 supersedes OSGM02 geoid model. Replaces ETRS89 to Newlyn height (1) (tfm code 10021). For reversible alternative to this transformation see ETRS89-GBR [OSNet v2009] to ETRS89-GBR [OSNet v2009] + ODN height (2) (code 9587)."]]

proj4.defs("EPSG:7711","+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=uk_os_OSGM15_GB.tif +multiplier=1 +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": "ETRS89-GBR [OSNet v2009] to ODN height (2)",
    "source_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"
                },
                {
                    "name": "Ellipsoidal height",
                    "abbreviation": "h",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 11008
        },
        "remarks": "Second national realization of ETRS89 in Great Britain. Replaces ETRS89-GBR [OSNet v2001] from 2016."
    },
    "target_crs": {
        "type": "VerticalCRS",
        "name": "ODN height",
        "datum": {
            "type": "VerticalReferenceFrame",
            "name": "Ordnance Datum Newlyn"
        },
        "coordinate_system": {
            "subtype": "vertical",
            "axis": [
                {
                    "name": "Gravity-related height",
                    "abbreviation": "H",
                    "direction": "up",
                    "unit": "metre"
                }
            ]
        },
        "id": {
            "authority": "EPSG",
            "code": 5701
        }
    },
    "method": {
        "name": "Geographic3D to GravityRelatedHeight (OSGM-GB)",
        "id": {
            "authority": "EPSG",
            "code": 9663
        }
    },
    "parameters": [
        {
            "name": "Geoid (height correction) model file",
            "value": "OSTN15_OSGM15_GB.txt",
            "id": {
                "authority": "EPSG",
                "code": 8666
            }
        }
    ],
    "accuracy": "0.008",
    "scope": "Derivation of gravity-related heights from GNSS observations.",
    "area": "United Kingdom (UK) - Great Britain onshore - England and Wales - mainland; Scotland - mainland and Inner Hebrides.",
    "bbox": {
        "south_latitude": 49.93,
        "west_longitude": -7.06,
        "north_latitude": 58.71,
        "east_longitude": 1.8
    },
    "id": {
        "authority": "EPSG",
        "code": 7711
    },
    "remarks": "OSGM15 supersedes OSGM02 geoid model. Replaces ETRS89 to Newlyn height (1) (tfm code 10021). For reversible alternative to this transformation see ETRS89-GBR [OSNet v2009] to ETRS89-GBR [OSNet v2009] + ODN height (2) (code 9587)."
}

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	<Layer srs="+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=uk_os_OSGM15_GB.tif +multiplier=1 +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 ( 7711, 'EPSG', 7711, '+proj=pipeline +step +proj=axisswap +order=2,1 +step +proj=unitconvert +xy_in=deg +xy_out=rad +step +inv +proj=vgridshift +grids=uk_os_OSGM15_GB.tif +multiplier=1 +step +proj=unitconvert +xy_in=rad +xy_out=deg +step +proj=axisswap +order=2,1', 'None');