The first two NLAs entered the market were Airbus Industrie’s A380 and Boeing777, and serve airports that currently serve the B747-400, However, Airbus Industrie’s super jumbo will be 11 feet longer, 41 feet wider, 15 feet taller and 400,000 pounds heavier than Boeing’s jumbo jet. So the airports must renovate and expand its infrastructure to accommodate NLA’s operations.
Air New Zealand Boeing 771`227-200er
Video embedded from YouTube on 11 August 2011
The airfield account for 80 to 95 percent of the total airport land area, the geometric design of an airfield should provide for efficiency in operations, flexibility and potential for future growth, as well as comply with the design standards developed by international and national civil aviation organisations, to promote maximum level of safety. Airside design requires many complicated and accurate calculations, and influenced by many factors, the introduction of the NLA will have obvious impacts on the following elements:
Larger wing span aircraft will add complication to maintain the required wingtip/operational separation between planes, in other words, normal separation space may block adjacent gates while loading and unloading from NLA, for example, A380. Some airports chose to park the aircraft on hardstands and use buses to transport passengers; however, this operation strategy is very expensive and inconvenient for passengers and service crews. (Yeamans, 20011)Many airports has built as many taxiways and aprons as possible in the limited amount of space, therefore it is virtually impossible for taxiway relocation projects to provide proper taxiway separation distances for NLA. Air traffic control may have to restrict the movement of NLA to specifit taxiway routings or keep other traffic clear of the area while the NLA taxi to their destination, but these solutions will increase traffic congestion. (U.S Department of Transportation, 19983)
Wingtip separation when loading and unloading aircrafts
(Picture embedded from Integrated on 14 October 2011)
Body weight and body length
Runway design include length, width, shoulders, blast pads, and stopways, and NLA will have impacts on these designs. Weight of the aircraft has a significant effect on the runway length, normally the greater the total weight (operating weight empty plus payload plus fuel) of an aircraft, the longer are the takeoff or landing distances; longer stage lengths means more fuel and therefore increased weight and longer take off distances. (Neufville & Odoni, 20034)Thus, with a massive body weight, A380 need to operate on a longer runway than the current to perform safe control.
FAA's Advisory circular AC 150/5325-4 has detailed methods to calculate runway length. With their high-lift generating wing designs, NLA's runway length requirements is similar to B747-400, therefore, any airport that's currently accommodating B747-400 will require no further modification on runway length. The table below shows the requirements for NLA:
|NLA||Runway Length Required In Feet (Meters)|
|B HSCT||11,000 (3,353)|
|MD HSCT||10,800 (3,292)|
(U.S Department of Transportation, 19983)
Aircraft scheduling and capacity planning
Aircraft scheduling and capacity planning are meant to enhance gate efficiency and profits. To avoid high passenger volume, aircraft could schedule NLAs to land or take off during off-peak hours. HOWEVER, this is against the “hub and spoke operations”, as well as contrary to overseas time slots. (Yeamans, 20011)
Runway capacity is a probabilistic quantity, a random variable which take on different values at different times, for example, the number of arrivals and departures that can be performed on a runway during any particular hour will depend on the mix of aircraft that will be using the runway at that time, if the mix included one or a few NLA, then the capacity will be lower than at times when the mix only consists smaller aircraft. Because large aircraft generate wake vortices that may pose a threat to planes flying right behind them. (Neufville & Odoni, 20034) For safety reasons, the air traffic management (ATM) require longer separation between pairs of successive aircraft whenever the first aircraft in the pair is a large and heavy one, also two NLAs will very unlikely to take off or land as a pair, and the NLAs would be scheduled to avoid peak hours to ensure the maximum runway capacity for the busiest periods.
No matter how advanced or primitive, every ATM system need to specify a set of required minimum separations between aircraft flying under instrument flight rules (IFR), and the separation requirements determine the maximum number of aircraft that can traverse each part of the airspace or can use a runway system per unit of time. For the complete runway separation requirements for different aircraft, please read Runway Separations.
B747-400 used to be the largest aircraft; many current airfields that are designed to service it. However,
|Airfield classification||FAA Design Group V||FAA Design Group VI|
|Aircraft may operate||B747-400||A380|
|Runway requirement||150 foot wide||200 foot wide|
|Taxiway requirement||75 foot wide||100 foot wide|
|Runway to taxiway||400 feet||600 feet|
|Taxiway to taxiway||267 feet||324 feet|
A380’s wingspan is close to 262 feet, it’s the first aircraft in FAA Design Group VI. To meet the requirement established for this category, runway and taxiway widths, as well as runway to-taxiway and taxiway-to-taxiway separations, will need to be increased. Folding wings technology might allow NLA to operate at existing Group V airfields; however, this is available to Boeing 777 but not A380. (Mollman, 20012)
How quickly and effectively an airport can confront an emergency situation is the most important issue for the introduction of NLA.FAA design standards for airport emergency plans can be found in two sources: Aviation Regulations (FARs) and Advisory Circulars. (U.S Department of Transportation, 19983) However, with the existence of NLA, the standards of the following areas will need to be reviewed:
FIRE PROTECTION AND EQUIPMENT The size and physical characteristics of the NLA will play an important role in determining the size and capability of the rescue and firefighting equipment required at an airport. The current airport firefighters will need to be equipped with long ladders, booms with skin penetrating devices, and other specific types of equipment to properly extinguish the fires for the larger size and multiple levels occupancy aircrafts. (U.S Department of Transportation, 19983)
EMERGENCY PROCEDURES NLA carries 20 to 30 percent more passengers and requires airports to designate additional emergency equipment, supplies, and personnel are available to properly respond to an emergency.Advisory Circular 150/5200-31, Airport Emergency Plan (AEP), provides guidance to the airport emergency plan; it should encompass procedures that are capable of handling an emergency involving the largest passenger aircraft served by the airport. AC 150/5200-31 recommends that civil airports practice a full-scale execution of an airport’s emergency plan once every 3 years, to identify deficiencies, misunderstandings, or confusion that may exist in the applicable AEP. For airports that serve NLA, this involves a significant increase in the number of participants and the possibility of a very chaotic situation. (U.S Department of Transportation, 19983)
NLA’s high passenger capacity may be eased the airside operation congestion, but on the other hand, this feature will create terminal and landside congestion, that could mean, the airports need to double size their waiting lounges, increase ticket processing capacity, expand baggage handling and customs areas, widen car park and taxi waiting areas, even though still may not be able to handle the surges of arriving and departing passengers.
If you think the passenger traffic in the video is bad enough, then try to imagine there're 800 more people in the picture.
Video embedded from Youtube on 11 August 2011
For the detailed impacts on passenger flow, please click here Impacts of NLA on passenger flow.
Upper level bridges
Double decker design isn't just on the new A380 but with the existence of the new large aircrafts, this feature will have a major impact on the airport design and operation requirements. In order to maintain competitive airline schedules and restrictive take-off/landing slots, double-decker designed aircrafts, such as A380, are designed to connect three passenger bridges to cope with the 90 minute turnaround demand. Many existing terminals would have to go through big structural modifications for the use of upper-level bridges. (Yeamans, 20011)
Upper level passenger bridge for A380
(Picture embedded from Sky scraper city on 11 August 2011)
Airports will require significant facility improvements to handle the large aircraft. The majority of these changes are upgrading to meet design group VI for most NLA, these are very expensive activities.
Want to know more?
- FAA: design standards
- Contemporary airport design
- Airside planning and designing
- Double-decker Airbus a show-stopper at Pearson
- Aircraft Runway Length Estimation