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LCQ14: Air traffic movements at the Hong Kong International Airport

     Following is a question by the Hon Kenneth Leung and a written reply by the Secretary for Transport and Housing, Professor Anthony Cheung Bing-leung, in the Legislative Council today (October 15):


     It has been reported recently that quite a number of flights have been delayed in taking off from or landing at the Hong Kong International Airport (HKIA) due to the implementation of air traffic flow control by the mainland authorities. There have also been press comments pointing out that the People's Liberation Army Air Force requires that an aircraft departing from Hong Kong must reach an altitude of over 15 700 feet before it enters the mainland airspace (such altitude restriction is commonly known as the "sky wall"). The sky wall has lengthened flight times and prevented the existing two-runway system of HKIA from optimising its operation efficiency, thus affecting air traffic movements. Besides, some concern groups have recently pointed out that the northbound routes recommended in the 1992 New Airport Master Plan have still not been opened. In this connection, will the Government inform this Council:

(1) of the number of times the Airport Authority or the Civil Aviation Department was notified by the mainland authorities of the implementation of air traffic flow control (broken down by mainland airspace over which air traffic flow control is implemented) and the total number of hours of delay in aircraft arrivals and departures caused by such control since 2010;

(2) of the number of flights which were delayed in taking off from or landing in Hong Kong due to the implementation of air traffic flow control by the mainland authorities, with a breakdown of the number by flight destinations and its percentage in the total number of aircraft movements, in each year since 2010, set out in Table 1;

(3) whether it conducted any study in the past three years on the effects of the "sky wall" on the number of aircraft movements; if so, of the details; if not, whether the authorities can undertake to conduct the study and publish the results; and

(4) of the reasons why the northbound air routes have still not been opened?



     Our reply to the various parts of the Hon Kenneth Leung's question is as follows:

(1) and (2) The Civil Aviation Department (CAD) has been monitoring closely the situation of delayed departure flights for the Mainland. The statistics from 2010 to September 2014 are set out in Table 2.  

     Separately, CAD does not have any breakdown on airspace control implemented by the Mainland or on the destinations of the delayed flights, nor the statistics regarding delayed arrival flights from the Mainland.

(3) To make sure that aircraft in adjacent airspaces could operate in a safe and efficient manner, an aircraft must reach a certain altitude before an air traffic control (ATC) unit may hand over the control in respect of that aircraft to another ATC unit. This is to ensure that when aircraft in adjacent airspaces fly in opposite directions, they could keep flying at different altitudes to prevent collisions. This air traffic management arrangement for flights to be separated by altitudes seeks to safeguard flight safety, and is commonly applied by busy airports all over the world, including those in London and New York.  This arrangement has no direct relationship with the time interval and space separation between runway movements, and hence does not affect runway capacity.

     Given the close proximity between Hong Kong International Airport (HKIA) and its Shenzhen counterpart and the fact that the two airports are separately managed by two ATC units in Hong Kong and the Mainland, an aircraft departing from HKIA must reach the designated handover altitude of 15 700 feet before it can enter the Mainland's airspace.  This designated altitude requirement is also applicable to aircraft flying from the Mainland into Hong Kong's airspace. After discussing with the Mainland's ATC unit, the two sides have since 2005 lowered the handover altitude from 15 700 feet to 12 800 feet during specified non-peak hours at night (that is, from 11pm to 7am the following day), thereby minimising detours made by aircraft.

(4) In accordance with the international standards and recommendations promulgated by the International Civil Aviation Organization, the development of flight paths should take into account the terrain environment, runway alignment, the prescribed obstacle clearances, airspace coordination with nearby airports, and so on.

     Due to the constraints presented by the high mountains around HKIA, and after giving due consideration to the relevant factors above, the two runways of HKIA are operating under an independent segregated mode of operations (that is, the North Runway is used exclusively for arrivals and the South Runway exclusively for departures), and it is not necessary to use flight paths north of the airport under this mode of operations.

     According to a runway capacity analysis for HKIA in 2008 conducted by the UK aviation consultant, the National Air Traffic Services, which is commissioned by the Airport Authority Hong Kong, the practical maximum capacity that can be achieved by the two runways of HKIA is 68 movements per hour. Over the years, through continuous improvements to flight procedures and operations, and efforts to optimise airspace structure as well as to increase the manpower of air traffic controllers and upgrade infrastructural facilities at the airfield, the CAD has gradually increased the capacity of the two runways in accordance with air traffic demand, from 50 movements per hour in 2004 to the current 65 movements per hour. The CAD will continue to further increase the capacity of the two runways to their practical maximum capacity of 68 movements per hour in 2015.

Ends/Wednesday, October 15, 2014
Issued at HKT 12:30


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