Noise causes annoyance, but its amount cannot simply be related to noise levels. Decision-makers often request that noise exposure is calculated for different times daily, evening, and night-time or their combination (Lden) in order to better understand the potential impacts the noise may cause.  But unfortunately, these level metrics are typically computed for longer periods only, i.e., a month, the busiest six months, or a year, thus blurring the annoying effect of some worse days or even some hours of the day. A more citizen-centric approach might consider the nature of aircraft noise to be a series of individual events rather than a continuous equivalent level. Lden can neither consider critical hours, such as trying to get some rest outside after work, the time when people try to fall asleep, or when they are in a light-sleep phase soon before getting up; nor can it tell too much about sleep disturbance by the noise.

The introduction of new metrics to use as an evaluation tool on the harmful effect of air traffic is not just a difficult scientific task, it is also a hard decision because there does not exist a universal, undisputed metric. Each of the metrics utilised nowadays emphasise one certain aspect of noise while suppressing the others. Instead of inventing new formulas of combined metrics, in ANIMA, we try to move the current, mainly equivalent-level oriented decision approach in a direction where more factors are considered.

Therefore, a tool has been elaborated, which can compute several metrics, each strongly related to annoyance. A strong emphasis has also been set on the ability of the tool to easily change scenarios, i.e., to analyse various possibilities quickly.

^{Please note that all examples presented here serve only to demonstrate the tool's capability and potential. Although you’ll see computed metrics around Budapest Airport, the applied schedules are fictional, so it is strongly emphasised that the reader shall not draw any conclusions on the situation around BUD airport.} 

^{Map visualisation window showing various metrics for one scenario. One can observe that areas defined by crucial limits of the metrics mark out somewhat different areas.}

The most important capability of the Virtual Community Tool is to compute various acoustical and non-acoustical indicators, including standardised quantities (e.g. L_DEN or L_night) and metrics that are customisable by the user. One example of such customisation is the ability to change the typical period of people's sleeping hours, which affects the calculation of the awakening indicator.

Also, a unique feature of the tool is that it enables the user to modify the global properties of the airport's traffic through a clean graphical user interface that is easy to handle. In particular, the following properties of air traffic can be adjusted:

• The global and the hourly number of operations can be modified, meaning that the traffic as a whole can be increased or decreased. Furthermore, the traffic can be reorganised among the hours of the day by moving a certain percentage of the traffic from one hour to one or many others. This feature is particularly useful for examining the day-evening-night balance of the noise and annoyance caused by the current or the planned air traffic;
• The usage of runways and flight paths, allowing the adjustment of the amount of traffic on them. Besides the ability to forecast the effects of introducing new flights, this feature can be especially useful for predicting the change of indicators by such events as a renewal of a runway;
• The composition of the fleet, i.e. the relative amount of different types of aircraft, allowing the replacement of older aircraft types by newer ones, as well as entirely banning operations of given aircraft types. This functionality allows for forecasting the effect of the renewal of the fleet of airlines.

The user may define areas for various land-use planning actions by simply marking them on the map. Area types include green parks, business areas, university campuses, or areas where window insulation for the houses is funded. The areas defined by the user affect the computation of both acoustical and non-acoustical indicators.

If a demographic map of the examined area is available, the VCT imports it automatically. Once the demographic map is loaded, the acoustical and annoyance metrics can also be visualised, taking the number of affected people into account, indicating the seriousness of possible aircraft noise-related problems. Furthermore, the demographic map may be supplemented by a so-called occupancy map, which describes - on an hourly basis - what percentage of the habitants are at home. This enables taking the number of affected people dynamically into account. This unique feature is also exploited in defining the land-use planning for the vicinity of the airport. As an example, it can be expected that a business area or a shopping centre is not inhabited during the night hours.

The user can either perform a series of adjustments on one scenario, resulting in a modified scenario or perform different adjustments on the same scenario and then saving them as separate scenarios.