Coordinate Convention

DOE-STD-3014-96

APPENDIX B

B.3.1 Coordinate Convention. At an airport, each runway is designated by two numbers (one

for each end). Each number designation is approximately one-tenth of the angle that

the extended runway direction makes with magnetic north. For example, depending on

its direction of use, a runway may be called Runway 4 or Runway 22. An aircraft

departing Runway 4 flies an approximate course of 40 degrees with respect to

magnetic north; similarly, an aircraft landing on Runway 4 also flies an approximate

course of 40 degrees prior to touchdown. Use of Runway 22 sets the flight course at

220 degrees with respect to magnetic north. Parallel runways receive similar numbers

with right (R) and left (L) designations.

To define aircraft crash locations relative to airfield runways and facilities, it is

necessary to establish a location coordinate system. This standard uses the Cartesian

coordinate convention with the following characteristics:

The origin of the coordinate system is at the center of the relevant runway.

The x axis coincides with the extended runway centerline; the positive direction

is the direction of flight.

The y axis is perpendicular to the x axis with the positive direction created by a

90-degree counterclockwise rotation of the positive x axis.

The coordinate system is depicted in Figure B-1.

B-4