AIRPORT NOISE ABATEMENT AND THE AVIATION INDUSTRY

Analysis of the relationship between airport efforts to reduce aircraft noise intrusion and the efficiency of air carrier operations shows conclusively that airlines incur significant costs related to noise abatement. Costs arising from inefficient flight tracks and runway utilization are readily estimated. Other costs, such as those related to capacity limits, fleet-scheduling constraints, and delays are more difficult to document but are generally recognized as very real and significant to the aviation industry. Increased costs can be expected in the future as communities continue to restrict airport operations and capacity enhancement in order to curb increases in noise levels. The ramifications of these restrictions are well illustrated by the current situation at Amsterdam’s Schiphol Airport.

Schiphol International Airport, Amsterdam

In 1998, the Dutch government imposed a noise pollution limit, or noise budget on Amsterdam’s Schiphol Airport. The limit was based on a total annual noise budget that allowed 380,000 flights in 1998, with allowable increases of 20,000 per year for five years, provided that there is no change in the noise contours. The noise budget is apportioned to airlines through the use of slots, each slot allowing an operation, with the number of slots being determined by an independent coordinator. In October of each year, the airport provides a usage plan for the following year, with allocations for each airline. The annual noise climate is predicted at 245 points and then recalculated monthly using actual traffic as available and projected traffic for the remaining months. As the year progresses, traffic is reassigned to different runways and night flights canceled to meet the annual budget at every point.

The restrictions brought about by this noise budget policy affect all airlines, domestic and foreign. As landing rights are often negotiated on a mutual basis, there is the possibility of retaliatory action against KLM (Schiphol’s major airline) at its foreign destinations. At best, airlines may have to re-negotiate their slots at many foreign destinations. The beneficial results of this policy have been that some airlines — usually the larger ones that have the flexibility — have opted to use quieter aircraft.

One of the problems faced by airlines is the uncertainty in operations due to sudden cancellation of flights required to avoid projected noise budget overruns. This can happen at any time in any season if the latest monthly noise climate calculation indicates that some points will exceed the budget by year-end. This may hit nighttime cargo operations particularly hard since the imposition of nighttime noise penalties makes canceling nighttime operations an attractive option for meeting the noise budget. In fact it has been stated that Schiphol, Europe’s fourth largest airport, may no longer be able to function as a cargo hub.

Some airlines — usually the smaller ones and the air freight carriers - have decided to go elsewhere. KLM is now concentrating on its most profitable flights and canceling others, and has openly discussed moving a portion of its operations base to other European airports, and the airport has raised the possibility of building a new facility on reclaimed land in the North Sea.

Safety has also been compromised at the airport. Late last year, one runway was closed to meet the budget at certain points, resulting in an aircraft sliding off the operating runway due to severe side winds.

The government’s actions have temporarily put an end to Schiphol’s plans for privatization. They have also raised the specter of tens of thousand’s of jobs being lost as Schiphol is prevented from being a European hub.

Need for Noise Research

Analysts recognize that there are three ways to reduce noise impacts: implementing noise management plans (as through curfews, preferential runway usage, noise abatement flight tracks, and slot rules), mitigating noise at the receiver (as with sound insulation), or reducing noise at the source (the aircraft itself). Of these three, noise management plans have the potential to severely disrupt interstate, or international, commerce and exert strong negative pressure on the aviation industry, as seen in the example above. Sound insulation has proven to be effective, but many communities demand an environment that is quieter overall, not just inside their homes. The potential for reducing noise at the source has been proven with the technologies used to develop Stage3/Chapter 3 aircraft. Unfortunately, scientists believe that the easier "fixes" have been made and the next level of significant noise reduction technology will be more difficult to achieve. Aircraft engine and airframe manufacturers have a vested interest in developing new technologies, but are unable to commit the necessary resources due to the extremely competitive industry climate.

This suggests that only dedicated research at the national level, such as by federally funded agencies who are charged with supporting the national interest, will be capable of meeting the pressing need for technological improvements. If quieter aircraft technology is not developed, it is very likely that community pressures to restrict airport operations will have an increasingly adverse impact on the aviation industry, as is the case at Schiphol Airport .