BRIDGES

AVIATION OBSTRUCTION LIGHTS ON BRIDGES

Bridges and other major projects, which has the potential to endanger aviation in navigable airspace or has the potential to interfere with the operation of navigation, should be lighted with aviation obstruction lights systems.

BASIC RULES

  • The number of light levels recommended depends on the height of the structure;
  • The number and arrangement of light units at each level should be placed so the lighting is visible from every angle in azimuth;
  • Lights are applied to display the general definition of an object or a group of buildings;
  • Width and length of buildings determine the number of lights installed at the top and at each light level.
Aviation obstruction system bridge

LIGHTS SPECIFICATIONS

  • Low intensity aircraft warning lights should be used for structure with H ≤ 45 m during night time, if those are considered inadequate, than medium – high intensity lights should be used.
  • Medium intensity aircraft warning lights type A,B or C should be used to lit extensive object (group of buildings or tree) or structure with 45 m < H ≤ 150 m.
  • Note: Medium intensity lights, type A and C should be used alone, whereas medium intensity lights, Type B should be used either alone or in combination with LIOL-B.
  • High intensity aicraft warning lights type A, should be used to indicate the presence of an object if its H > 150 m and an aeronautical study indicates such lights to be essential for the recognition of the object by day.

AVIATION OBSTRUCTION LIGHT MARKINGS

There is 3 option for lighting a bridge with aviation obstruction light systems.

  1. If the bridge is to be lighted only at night with red light
    • If the authorities state that there is no need to light the day
    • If the bridge marked with paint (white-red strip)
  2. If the bridge is to be lighted day and night with white light
  3. If the bridge is to be lighted with white light at daytime and with red light at night time
    • If the authorities state that white light is too much discomfortable at night

1 – IF THE BRIDGE IS TO BE LIGHTED ONLY AT NIGHT

On Bridge aircraft warning lights
HEIGHT, LENGTH & WIDTH N° OF LEVELS & N° OF LIGHTS PER LEVELS
H ≤ 45m Only one level: Low intensity
 

45m < H ≤ 105m

2 levels:

Top level: Medium intensity – B Type;

Intermediate level: Low / Medium intensity – B Type.

 

 

105m < H ≤ 210m

4 levels:

Top level: Medium intensity – B Type;

First Intermediate level: Low / Medium intensity – B Type;

Second Intermediate level: Medium intensity – B Type;

Lower Intermediate level: Low / Medium intensity – B Type.

2 – IF THE BRIDGE IS TO BE LIGHTED DAY AND NIGHT WITH WHITE LIGHTS

High intensity HIOL aviation obstruction light on bridge
HEIGHT, LENGTH & WIDTH N° OF LEVELS & N° OF LIGHTS PER LEVELS
H ≤ 105m Only one level: Medium intensity – A Type
 

105m < H ≤ 210m

2 levels:

Top level: Medium intensity – A Type;

Intermediate level: Medium intensity – A Type.

 

210m < H ≤ 315m

3 levels:

Top level: Medium intensity – A Type;

Intermediate level: Medium intensity – A Type;

Lower Intermediate level: Medium intensity – A Type.

3 – IF THE BRIDGE IS TO BE LIGHTED WITH WHITE AND RED LIGHTS

HEIGHT N° OF LEVELS
 

H ≤ 105m

2 levels:

Top level: Medium intensity – AB Type;

Intermediate level: Low / Medium intensity – B type.

 

 

 

105m < H ≤ 210m

4 levels:

Top level: Medium intensity – AB Type;

First Intermediate level: Low / Medium intensity – B Type;

Second Intermediate level: Medium intensity – AB Type;

Lower Intermediate level: Low / Medium intensity – B Type;

Medium intensity aircraft warning lights on bridges