Noise and Track Monitoring
TAG Farnborough has installed a comprehensive system of
aircraft monitoring. The monitoring system, known as a
Noise and Track Monitoring System (or NTMS) comprises of
two major components, a noise monitoring element, and an
aircraft monitoring element.
The use of a combined noise and track monitoring system,
allows satisfaction of a number of the requirements of the
Town and Country Planning Act Section 106/299A
Agreement between Rushmoor Borough Council and the
airport Operators TAG Farnborough Airport Ltd as well as
provided detailed information on the noise and airspace
environments around Farnborough.
Noise
The noise monitoring system installed at the airport
consists of two permanent and one portable monitoring
terminal. The two permanent (static) monitors have been
located at comparable locations on the extended runway
centreline at either end of the runway.
The portable NMT is used to carry out ad-hoc monitoring
at sites within the Airport boundary and out in the local
community and has most recently been used in
conjunction with the work of the Quiet Flying Program.
It has been located at local residential properties, local
schools and within MOD operated areas as a part of this
work.
The Noise Monitoring Terminals record “noise events” twenty four hours a day,
these are identified by noise levels reaching a specific threshold for longer
than a designated duration.
The software interrogates radar data and correlates noise events to actual
aircraft identified within a search radius of the noise monitors.
Event identification parameters in use at each monitoring location have been
calculated to minimise the intrusion of unrelated noise sources.
Leq values are calculated using actual noise data collected by the monitors.
An Leq is a weighted time average value that represents a noise energy level
equivalent to that actually experienced by a human ear at ground level.
All Leq’s have been calculated based on actual recorded sound levels in dB (A).
dB (A) refers to an A weighted decibel scale. The human ear does not detect all pitches of
sound equally efficiently; most sound measurement therefore uses a scale which weights
different pitches or frequency of sound according to human sensitivity to them.
This scale is known as the A weighted decibel scale. Leq values recorded by the
monitoring apparatus are therefore time averaged “A” weighted values.
An example of background noise data, in the raw form, recorded by one of the
monitoring terminals, is given in this image
Track
The second element of the noise monitoring system uses track data derived from the
radar system. The system uses this track data to identify aircraft in the vicinity of noise
monitors, in order to correlate events as aircraft noise events.
Speed is not recorded. It is Altitude (above mean sea level) that is recorded rather than
Height (above ground level).
Along with the aircraft “tracks” aircraft type and registration, operation type, and runway
used is recorded and correlated with noise events. Examination of detailed flight paths as
generated by the track monitoring system allows for the identification of any flight
operations that fail to comply with noise abatement procedures in force at the airport. It
also allows for easy identification of other airspace users not associated with
Farnborough.
An example of track data can be viewed in this image.
Actual radar track records, for Farnborough flights, including height data and aircraft type
information are used periodically to produce noise contours using the FAA’s Integrated
Noise Model (or INM). The INM is increasingly being adopted as the standard tool for
assessing noise impacts from significant sources such as major roads and airports under
the European Noise Directive 2002/49/EC.
All contours produced so far using Farnborough track data have shown that the operation
being carried out is fully compliant with the requirements of the planning permission
granted.
These procedures are to be used at all times. However, the requirements may at any time
be departed from to the extent necessary for avoiding immediate danger or complying
with ATC instructions.
ENVIRONMENT PAGES
FARNBOROUGH AERODROME CONSULTATIVE COMMITTEE
An independent Consultative Committee established by TAG Farnborough in accordance with a
Section 106 agreement of the Town and Country Planning Act
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