Are you being a good neighbour?
Managing the impact of aircraft noise in your neighbourhood.
Recently, I became involved in a project to the update the SID’s and STAR’s of an International Airport. The procedures being revised were created in the 1970’s and are based on the navigation technology available at that time. Navigation technology used in that era required the protection of significantly more airspace to allow for wider aircraft instrumentation and ground facility signal inaccuracy.
One example of an airway allowing for this increased inaccuracy is that of an airway utilizing NDB (non-directional beacon) ground stations for position fixing. (I hear many asking, ‘ NBD in this era of RNAV/GPS overlays?’) The NDB airway incorporated a wide cone of protected airspace due to the systemic uncertainty of actual position information. Imagine for a moment an ice-cream cone laid on its side, the NDB will be at the point of the cone and as you move away from the bottom of the cone/NDB, the volume of protected airspace increases according to increased likelihood of positional error.
The airway’s wide footprint had the added effect of diluting the noise footprint of the traffic on a single route. If 10 aircraft are following the same airway, and the airway is 10 miles wide, this meant that the possibility of two aircraft following the exact same track over the ground was remote.
The increased precision of the navigational instruments and the availability of GPS has been a major improvement in both the cockpit and from an air traffic management point of view.
Airspace planners have welcomed the increased predictability of the tracks to be flown. Regulators have used the evidence produced from historical track monitoring and increased positional reliability to justify reducing lateral track separation standards in congested airspace in order to increase airspace capacity in the vicinity of busy airports. This is evident in the reduction of RNAV performance criteria from Required Navigational Performance (RNP) 5 to RNP 1 in many Terminal Control Areas. Airline operators have also welcomed the increased predictability these precision tracks provide, as they are now able to forecast fuel burn more accurately. Pilots are able to fly the same track profile almost every time.
This increased precision has had some unexpected, adverse effects on the population surrounding the airport. Where the arriving or departing aircraft would have previously be dispersed in a swathe 5 nautical miles (NM) wide, the aircraft are now concentrated in a corridor 1 NM wide. Initially you may think... “We have just provided a measure of noise relief for 80% of the previously affected area”. While this may be true, you have also increased the traffic footprint of the 1 NM corridor by 400%!
While the benefits of incorporating the latest RNAV technology are abundantly evident to those in the aviation industry, it is important to remember many
people do not understand why an aircraft must fly at low altitudes over an area more than 10 miles from an airport.
The response of the local community to the presence of an international airport in the local area is generally positive. Some of the obvious benefits offered by the presence of an airport are:
• Employment
• Economic activity
Prestige of having an airport close by Ease of travel for business and leisure
• Incoming tourist travellers
The majority of complaints from neighbouring communities relating to an airport’s activity are directly attributable to aircraft noise and the disturbance this causes.
Most airports have a quiet hours movement policy. These noise restrictions along with the reduced noise footprint of modern engines has had a dramatic impact on reducing the actual noise created by flying activities. The perceived disruption is another issue.
There are a number of activities an airport is able to engage in that will reduce the negative feelings toward the aircraft operations. These engagement activities do not have to compromise the airport’s operation. The engagement will involve the building of a relationship between the airport and the surrounding community.
Most people are generally more receptive and acceptant of disruptive activities if they understand what, and why, it is happening.
Noise is a by-product of any industrious activity. Think for a moment about the sound of pounding nails while building a house or the laughter of children in a playground. If your neighbours feel like they are being treated with respect and have had their concerns genuinely heard and acted upon, the relationship between the airport and the neighbouring community will begin to flourish.
If you would like to discuss this issue with me just drop me a line and I will respond to you as soon as I can.
