1. CEE 4674 – Airport Planning and Design (copyright A. Trani)! 1
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Dr. Antonio A. Trani
Professor of Civil Engineering
Virginia Polytechnic Institute and State University
February 25, 2009
Blacksburg, Virginia
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CEE 4674 Airport Planning and Design
Geometric Design I
Addendum 1

2. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Organization of this Presentation
• Geometric design standards for runway exits
• Examples
• Design rationale for taxiways and taxilanes
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3. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Geometric design Standards for Runway Exits
• Sources:
• FAA AC 5300-13 (Chapter 3)
• ICAO Aerodrome Manual Volumes 1 and 2
• Design principle:
• Provide ample space for aircraft to maneuver out of the
runway
• Make the runway exits easily identifyable
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4. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Right-Angle Exits
• Baseline centerline radius is 250 feet
• Pavement edge radius varies according to runway width
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5. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Sample Implementation (ATL)
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R = 250 feet!
Runway!
(150 feet wide)!
Parallel Taxiway!
90 degree!
Runway Exit!
Source: Google Earth!

6. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
45 Degree Angle Runway Exit
• Nominal 800 feet centerline radius
• 600 feet pavement edge radius
• Old design – FAA has dropped diagram from AC 5300-13
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7. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Issues with 45 Degree Runway Exits
• Narrow width at tangency point (only 40 feet)
• Only useful for busy general aviation airports
• Since the FAA has dropped discussion of this design in
the latest releases of the AC 5300-13 the geometry should
be use with caution
• The 30 degree standard design seems to be favored in case
peak operations exceed 30 per hour
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8. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Acute Angle or High-Speed Runway Exit
30 Degree (Old Standard)
• Nominal 1800 feet centerline radius
• 1600 feet pavement edge radius
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9. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Acute Angle or High-Speed Runway Exit
30 Degree (New Design)
• Nominal 1400 feet centerline spiral
• Can use the FAA computer program AD42.exe
application for design (companion computer program to
AC 5300-13)
• See example on page 48-1 in Chapter 4 of AC 5300-13
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10. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Specification of a High-Speed Runway Exit
• x-y coordinates of centerline
• Left and right offset distances from the centerline
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11. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Specification of High-Speed Runway Exit
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12. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example in AC 5300-13
(see page 48-1 in FAA AC 5300-13)
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13. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example Problem in AC 5300-13
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14. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example Problem in AC 5300-13
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15. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Explanation
• The intersection angle is negative (-30 degrees) so this
turn is to the left
• The offsets (both right and left) decrease as a function of
station length to make the transition the runway exit width
from 150 to 75 feet
• The centerline angle increases from zero at the start of the
runway exit point to 30 degrees as required by the
geometry
• The steering angle provides a measure of how much effort
is required by the nose gear to keep with the centerline
geometry
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16. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example Implementation (ATL)
30 Degree Angle Runway Exit
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Source: Google Earth!
1400 foot spiral!
Runway!
(150 feet wide)!
Parallel Taxiway!
250 feet radius !
reverse geometry!
800 feet radius!

17. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Issues with 30 Degree Runway Exits
• The FAA recommends a minimum runway-taxiway
separation of 600 feet for High-Speed runway exits
• Some airport have used 30 degree runway exits with down
to 400 feet (avoid!)
• The result is low exits speeds and possible issues with
busting hold lines
• Be careful and try to provide the minimum 600 foot
recommended distance
• Limited pilot visibility while crossing active runways
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18. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Sample Limited Visibility on High-Speed
Runway Exit
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Final turning angle at hold line = 30 degrees!

19. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example of Limited Visibility due to
Short Runway-Taxiway Distance
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20. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Airbus A340-600 Visibility from Cockpit
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Source: Airbus!

21. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Example of Limited Visibility Driven by Hold
Line Location
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• Before the aircraft nose reaches the hold line, the
aircraft wingtip violates the hold line distance!

22. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Taxiway-Taxiway Junctions
• For dimensions consult FAA 150/5300-13 Table 4-2
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23. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Table 4-2 in AC 5300-13
Taxiway Fillet Dimensions
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24. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Taxiway-Taxiway Junctions
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• Sample solution shown for ADG VI
• For other groups consult FAA 150/5300-13 Table 4-2

25. CEE 4674 – Airport Planning and Design (copyright A. Trani)!
Sample Junction
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