(ATC map with hypothetical annotation by local leader)
The below two articles are evidence of the difficulties of introducing the operational benefits of NextGen/SESAR and of considering the impacts of these changes on the citizenry. The lessons learned here and in Europe should cause both governments to consider slight resetting of their ATC tactics now.
Air traffic is a complex discipline. It involves:
the rate of climb/descent,
the route(s) interaction with other flight patterns,
the efficiency of transfer of traffic from/to higher altitudes as well as the rate of acceptance/exiting of flights by the runways,
the calculus of various configurations on the airport’s capacity, and
last but not least, the impact on the populace under the flights.
These variables are not subject to optimization calculations. The analyses frequently are based on numbers adjusted by more subjective judgments. The process of defining the architecture for the airport’s airspace is very recondite and is hard to explain to the average layperson.
The noise generated by aircraft can be scientifically and precisely defined by acoustics. The energy is measured by instruments and then summarized by a day/night metric.
The human experience of sensing noise is the subject of an academic discipline called psychoacoustics. The first syllable of this label reflects that of all of the human senses, hearing is the most subjective. More than smell or sight or touch or taste, a person’s reaction to noise can be influenced by other factors. Motorcycles usually, for example, are rated by individual subjects as being noisier than the instruments show. Airplanes also have caused the same reactions.
Among the world of aircraft noise experts, there is considerable debate about both the metric’s calculation and the thresholds which should be used as decisional criteria. The FAA is deep in discussions over these significant policy decisions.
What is not subject to debate is the negative responses here and on the Continent by the airport neighbors. The new procedures are supposed to reduce fuel consumption and limit the variances from flight patterns (i.e. reduce the noise footprint). The new patterns have resulted in a citizen uproar about the NextGen/SESAR “improvements.”
The introduction of NextGen and SESAR is the intersection of new technologies and noise impact. The Governmental Accountability Office expressed concerns that affected communities that were previously unaffected or minimally affected by aircraft noise would rebel. It might be argued that the existing quieter Stage III aircraft, the larger environmental benefits and safety considerations might justify a Categorical Exclusion or some other short-cutting of the environmental review. If it was deemed that an Environmental Assessment or the dreaded Environmental Impact Statement under NEPA must be invoked, then the implementation of these needed ATC improvements would be inordinately delayed.
At some point in time a court may decide what NEPA process or exclusion should be followed. In the interim, the FAA and EUROCONTROL should consider some improvement in their introduction of these ATC processes.
The regulator would be well advised to involve local representatives who know the “turf”. Controllers know the airspace but they are not expected to know what is on the ground. An industrial park makes a far better area to absorb noise than a hospital or school. Major ground traffic arteries, i.e. a train track or subway line or major highway, are already subject to a fair amount of noise already and thus could mitigate the impact on the community. By delaying descent by some distance, the elevated flight would not be as loud over a sensitive area. The examples of what neighborhood knowledge might contribute to a more friendly approach to designing a new flight track. No, the trade-off in options cannot compromise safety, but where there is some flexibility discretion should be exercised to reduce the impact.
Involvement by some well-respected local leaders will also help with the new ATC architecture introduction. By participating, these individuals will understand the trade-offs among safety, noise and efficiency.
Equally important is pre-education. As mentioned before hearing is highly subjective, a small increment of noise over a low ambient basis may be perceived as a drastic change, while the instrument readings affirm that it was not significant. To anticipate this reaction and take preventative action, the ATC provider would be wise to calibrate the senses. It would be helpful to bring equipment which could familiarize the affected citizens with the actual noise levels. As a bit of base information, it would be good to emit sound levels of the Stage I, II and III to hear the progress, which is substantial. Then, the sound machine could produce a variety of noise levels and in that package would be the neighborhood’s current noise, the expected exposure of the noisiest aircraft and the average sound to be incurred.
When the new ATC procedure is implemented and after such a pre-education, the impacted residents will recognize what the level of impact from the ATC provider’s education. Such knowledge may reduce their response by having calibrated their expectations.
There is no gain to keeping the new audience in the dark. Without knowledge of what will be coming, the individual’s uneducated response is likely to be at the high end of the negative scale.
The FAA and EUROCONTROL face difficult tasks trying to balance the important variables. A surprise introduction of a new noise footprint will be inevitably negative. By trying to incorporate neighborhood knowledge and by taking the time to educate those to be impacted, the adverse response may be minimized.
Share this article: