Airy¶
The Airy projection is an azimuthal minimum error projection for the region within the small or great circle defined by an angular distance, \(\phi_b\), from the tangency point of the plane \(( \lambda_0, \phi_0 )\).
Classification |
Azimuthal |
Available forms |
Forward spherical projection |
Defined area |
Global |
Alias |
airy |
Domain |
2D |
Input type |
Geodetic coordinates |
Output type |
Projected coordinates |

proj-string: +proj=airy
¶
Options¶
- +lat_b¶
Angular distance from tangency point of the plane \(( \lambda_0, \phi_0 )\) where the error is kept at minimum.
Defaults to 90° (suitable for hemispherical maps).
- +no_cut¶
Do not cut at hemisphere limit
- +lat_0=<value>¶
Latitude of projection center.
Defaults to 0.0.
Note
The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the "r" character.
Example: +lat_0=1.570796r
See Projection Units for more information.
- +lon_0=<value>¶
Longitude of projection center.
Defaults to 0.0.
Note
The default convention is to interpret this value as decimal degrees. To specify radians instead, follow the value with the "r" character.
Example: +lon_0=1.570796r
See Projection Units for more information.
- +x_0=<value>¶
False easting.
Defaults to 0.0.
- +y_0=<value>¶
False northing.
Defaults to 0.0.
- +R=<value>¶
Radius of the sphere, given in meters. If used in conjunction with
+ellps
,+R
takes precedence.See Ellipsoid size parameters for more information.