RUNWAY OBSTRUCTIONS

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

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

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, 10000 ft Conical 4000 feet wide beyond horizontal 20:1 slope All from runway centerline See table 7-6

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

Example (1/4) Precision instrument runway 600 ft AMSL Runway length 10000 ft Center of runway (0,0,600) Coordinates of various points

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

Example (3/4) Horizontal surface: 10000 ft wide, 150 ft above runway Conical surface: 4000 ft wide, 20:1 slope Approach surface: 50000 ft long; outer edge 16,000 ft

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) (8000-500)/(50000-0) = (Y-500)/(X-0) (7500)/(50000)X = (Y-500) Add back in 5200’ (3/20) X + 500 = Y X’: 9803.9 Y: 1970.6 X: 15003.9 Y: 1970.6 Z: 796.1 X2 + Y 2 = 100002 Z = 9803.9* 1/50 = 196.1 Add back in 600’ AP Elevation