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

Airy

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=1.5708r

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=1.5708r

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.