Question: Centerline Perpendicular Points are required for which navigational aids? And how should I enter them?


Answer: Provide an Airport Control Point where the pointType attribute is set to CENTERLINE_POINT at the point along the centerline or extended centerline for the navaids listed in Section 5.8.3 (ILS, MLS, PAR, TLS, and VGSI). Enter the straight line distance (no vertical deviations following the undulation of terrain between the points) from the navaid’s Horizontal Survey Point to a point along the Runway Centerline where the centerline and the bearing to the navaid form a 90° angle.

Enter 0 for the centerlineDistance for other types of navaids where centerline perpendicular points are not required.

Note for perpendicular points to pass validation tests, they must meet the following conditions:

· The Runway End points that define the centerline the perpendicular point is on must also be submitted along with the perpendicular point(s).

· You must have a valid runway the perpendicular point is on.

· The status attribute of the perpendicular point must be set to the same value as the navaid.

· The pointType attribute must be set to the RUNWAY_CONTROL_POINT enumeration value.

· The location of the perpendicular point must be within 1 foot of the point along the centerline directly abeam the navaid.

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