# Hub Airport End-Around Taxiway Construction Planning Development: A Review
## 4 The Construction Principles and Key Points of End-Around Taxiway Layout  
### ICAO and FAA Recommendations for EAT Planning  
ICAO has published Standards and Recommended Practices (SARPs) for civil aviation, which are available in 19 annexes. Annex 14 Aerodromes Volume I Aerodrome Design and Operations [70] covers the design requirements for airports, but it does not provide specific guidance on the design of taxiway fillets. The annex only provides a basic definition of taxiway fillets and offers simple design guidance, but it does not cover specific details, so its guidance is limited:  
1. Sufficient space is required between the landing threshold and the taxiway centerline where it crosses under the approach path to enable the critical taxiing aircraft to pass under the approach without penetrating any approach surface. 2. The jet blast impact of aircraft taking off should be considered in consultation with aircraft manufacturers; the extent of take-off thrust should be evaluated when determining the location of a perimeter taxiway. 3. The requirement for a runway end safety area, as well as possible interference with landing systems and other navigation aids, should also be taken into account. For example, in the case of an ILS, the perimeter taxiway should be located behind the localizer antenna, not between the localizer antenna and the runway, due to the potential for severe ILS disturbance, noting that this is harder to achieve as the distance between the localizer and the runway increases. 4. Human factors and issues should also be taken into account. Appropriate measures should be put in place to assist pilots in distinguishing between aircraft that are crossing the runway and those that are safely on a perimeter taxiway. FAA AC No 150/5300-13B is a section in the airport design chapter that describes the design requirements for the EAT and the visual obstruction screens used to help pilots distinguish between aircraft on the EAT and those crossing the runway. This is related to earlier studies in the United States on EATs at airports such as ATL, DFW, and DTW. The Federal Aviation Administration (FAA) in the United States has recommended the following guidelines for the design of end-around taxiway layouts [67]:  
1. Locate the EAT centerline a minimum of 1500 feet (457 m) from the departure end of the runway. 2. The minimum length of that portion of the EAT crossing the extended runway centerline at the minimum distance of 1500 feet (457 m) is equal to the width of the departure surface of the Departure End of Runway (DER). 3. Increase the minimum distances as necessary to prevent aircraft tails from penetrating the 40:1 departure surface and any surface identified in FAA Order 8260.3. 4. Initiate an airspace study for each site to verify that the tail height of the critical design group aircraft operating on the EAT does not penetrate these surfaces. 5. The airspace study will also confirm compliance with Part 121, S121.189, Airplanes: Turbine Engine Powered: Takeoff Limitations, which requires the net takeoff flight path to clear all obstacles either by a height of at least 35 feet (10.5 m) vertically or by at least 200 feet (61 m) horizontally within the airport boundaries. 6. In addition to the critical aircraft tail height, the elevation of the stop ends of the runway relative to the elevation of points along the EAT is a factor in determining conformance with clearance criteria. 7. Locate the EAT outside of ILS critical areas. A typical EAT is shown in Figure 11[67]. The distance between the centerline of the taxiway and the Departure End of Runway (DER) is the determining factor in its design. This is influenced by many factors, including the aircraft type for the taxiway and runway,approach surfaces, takeoff climb surfaces, missed approach surfaces, use strategy for the taxiway, and communication and navigation facilities [71].