1. RUNWAY OBSTRUCTIONS

2. Runway Obstructions Need to provide a clear path for aircraft
Landing
Take off
According to FAR Part 77

3. Runway Areas (1/3) 1 4 2 3 1 Primary Surface 2 Horizontal Surface
3 Conical Surface
4 Approach Path

8. Runway Areas (2/3) Primary Horizontal Conical
200 ft longer than R/W at each end
Width 250, 500, 1000
Horizontal
150 feet above runway
Width 5000, ft
Conical
4000 feet wide beyond horizontal
20:1 slope
All from runway centerline
See table 7-6

9. Runway Areas (3/3) Approach Length 5000, 10000, 50000 ft
Slope 20:1, 34:1, 40/50:1
See table 7-6
Outer end

11. Example (1/4) Precision instrument runway 600 ft AMSL
Runway length ft
Center of runway (0,0,600)
Coordinates of various points

12. Example (2/4) Primary surface: 200 ft from runway edge, 1000 ft wide
Z: 600
X: 5200
Y: 0
Z: 600
Primary surface: 200 ft from runway edge, 1000 ft wide

13. Example (3/4) Horizontal surface: 10000 ft wide, 150 ft above runway
Conical surface: 4000 ft wide, 20:1 slope
Approach surface: ft long; outer edge 16,000 ft

14. Example (4/4)
5200’
Displace x coordinate for ease of computation
X2: 50000
Y2: 8000
X1: 0
Y1: 500
Intersection of Primary Surface and Flight Path …
Using similar triangles, (Y2-Y1)/(X2-X1) = (Y-Y1)/(X-X1)
( )/( ) = (Y-500)/(X-0)
(7500)/(50000)X = (Y-500)
Add back in 5200’
(3/20) X = Y
X’: Y: X: Y:
Z: 796.1
X2 + Y 2 =
Z = * 1/50 = 196.1
Add back in 600’ AP Elevation