Identification or Code Beacon
An identification or code beacon is required when the airport rotating beacon is more
than 5,000 feet from the nearest runway or where the rotating beacon serves more than
This beacon is a nonrotating, flashing omnidirectional light visible 360 degrees. The
identification or code beacon flashes a color-coded signal at approximately 40 flashes
per minute. The signal is assigned a code of characters to identify a particular airfield.
The identification beacon shall be operated whenever the associated airport rotating
beacon is operated.
Obstruction lighting consists of flashing and steady-burning red lights. Extremely tall
structures require high-intensity strobe lights during both day and night. Obstruction
lights are used to define the vertical and horizontal limits of objects that are hazardous
to aircraft operation. Obstruction objects include permanent construction hazards,
natural hazards, fixed equipment, and all installations that encroach on the standard
airfield clearance surfaces. When repair or construction constitutes a temporary hazard
to air navigation, these areas must be adequately lighted with temporary obstruction
Obstructions are defined as those objects that penetrate the imaginary surfaces defined
in Airfield Safety Clearances, NAVFAC P-80.3. The requirements for lighting
obstructions and other hazards to air navigation are set forth in the General
Requirements for Shorebased Airfield Marking and Lighting, NAVAIR 51-50AAA-2.
Various runway lights are installed at airports to provide visual guidance at night and
under low-visibility conditions for aircraft during takeoff and landing.
Runway Light System Classifications
Runway light systems are classified according to the intensity or brightness that they
produce: high-intensity runway lights (HIRL), medium-intensity runway lights (MIRL),
and low-intensity runway lights (LIRL). Navy requirements indicate that HIRLs shall be
used for all new runway edge lighting installations and should be considered for
replacement or improvements to existing runway edge lighting systems.
Runway Edge Lights
Runway edge lights form the outline of the runway for night operations or during periods
of reduced visibility. These lights are on both sides of the runway, extending the entire