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Geodetic CRS: OSGB36
Datum: Ordnance Survey of Great Britain 1936
Ellipsoid: Airy 1830
Prime meridian: Greenwich
Data source: EPSG
Information source: Heathrow Airport Limited documents "HAL_10000-XX-DR-XXX-000151_V4p0_P2.xlsx" and "Coordinate Systems - Airport Grid Spatial Project".
Revision date: 2026-03-05
Scope: Engineering survey, topographic mapping.
Remarks: Defines Heathrow Airport Grid absolute position and orientation, so considered error-free.
Method: Similarity transformation
Area of use: UK - Heathrow airport and surrounding area.
Description: (0,)
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Definition: OGC Well Known Text 2 (2019)
COORDINATEOPERATION["OSGB36 / British National Grid to Heathrow Airport Grid (1)", VERSION["HAL-Gbr LHR"], SOURCECRS[ PROJCRS["OSGB36 / British National Grid", BASEGEOGCRS["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]], ID["EPSG",4277]], CONVERSION["British National Grid", METHOD["Transverse Mercator", ID["EPSG",9807]], PARAMETER["Latitude of natural origin",49, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8801]], PARAMETER["Longitude of natural origin",-2, ANGLEUNIT["degree",0.0174532925199433], ID["EPSG",8802]], PARAMETER["Scale factor at natural origin",0.9996012717, SCALEUNIT["unity",1], ID["EPSG",8805]], PARAMETER["False easting",400000, LENGTHUNIT["metre",1], ID["EPSG",8806]], PARAMETER["False northing",-100000, LENGTHUNIT["metre",1], ID["EPSG",8807]]], CS[Cartesian,2], AXIS["(E)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["(N)",north, ORDER[2], LENGTHUNIT["metre",1]], ID["EPSG",27700]]], TARGETCRS[ ENGCRS["Heathrow Airport Grid", EDATUM["Heathrow Airport Grid"], CS[Cartesian,2], AXIS["(E)",east, ORDER[1], LENGTHUNIT["metre",1]], AXIS["(N)",north, ORDER[2], LENGTHUNIT["metre",1]], ID["EPSG",11378]]], METHOD["Similarity transformation", ID["EPSG",9621]], PARAMETER["Ordinate 1 of evaluation point in target CRS",-504786.4675, LENGTHUNIT["metre",1], ID["EPSG",8621]], PARAMETER["Ordinate 2 of evaluation point in target CRS",-156728.1037, LENGTHUNIT["metre",1], ID["EPSG",8622]], PARAMETER["Scale factor for source CRS axes",1.000259617024, SCALEUNIT["unity",1], ID["EPSG",1061]], PARAMETER["Rotation angle of source CRS axes",0.026361909134441, ANGLEUNIT["radian",1], ID["EPSG",8614]], OPERATIONACCURACY[0.0], USAGE[ SCOPE["Engineering survey, topographic mapping."], AREA["UK - Heathrow airport and surrounding area."], BBOX[51.42,-0.56,51.52,-0.37]], ID["EPSG",11388], REMARK["Defines Heathrow Airport Grid absolute position and orientation, so considered error-free."]]
Definition: JSON
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Definition: Mapnik
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Definition: SQL (PostGIS)
INSERT into spatial_ref_sys (srid, auth_name, auth_srid, proj4text, srtext) values ( 11388, 'EPSG', 11388, '+proj=affine +xoff=-504786.4675 +s11=0.999912071814854 +s12=0.0263656990790156 +yoff=-156728.1037 +s21=-0.0263656990790156 +s22=0.999912071814854', 'None');
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