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NEVAC Project

Welcome to the NEVAC website. Whether you are new to the European capacity planning process or a regular NEVAC user, there’s bound to be some relevant information here for you. Please take 10 minutes to browse through the NEVAC help documentation; it’s designed to give you all the essential information quickly, allowing you to understand the underlying analysis methodologies and to start using the latest version of NEVAC in your capacity planning activities.

NEVAC: A Capacity Analysis Tool

NEVAC is a stand-alone desktop application using CFMU data for long-term ACC and ECAC network capacity planning. NEVAC offers an intuitive, planner-orientated interface with a low barrier to entry for new users. NEVAC is not another fast-time simulator using flight performance criteria to simulate flight trajectories. Instead NEVAC re-uses simulated or radar-generated 4D flight trajectories provided by external tools and focuses on complex operationally-relevant network analysis and optimisation functionalities.
NEVAC is used by planners, capacity managers, flow managers and other operational staff responsible for managing ACC and Network capacity.

Capacity Planning

The role of NEVAC in evaluating and supporting LCIPs is to allow ANSPs to convert planned operational changes at the sector level into ACC capacity baseline changes at the ACC level.
ACC capacities reflect how ACC throughput can be limited by aspects of capacity management. They capture operationally-relevant criteria such as an opening scheme’s load distribution and peak demand capacity.
NEVAC is used in capacity planning activities to:
  • run ACC capacity assessments of past performance to determine the agreed baselines each year.
  • evaluate and support LCIPs which outline how each ANSP will meet an agreed capacity target.

NEVAC Functionalities

  • Calculate ACC capacity baselines
  • Generate future traffic samples
  • Optimise ACC configuration opening schemes, balancing controller hours with capacity overloads and related delays
  • Compare planning scenarios using built-in ATFM simulation capabilities
  • Study airspace reorganization options using virtual ACCs
  • Visualise load distribution, saturation, complexity and traffic mix analysis
  • Model procedural changes such as multi-sector planning or degraded operational scenarios at reduced capacity
  • Browse and Edit all environment and traffic data
  • Capture groups of flights by defining detailed custom traffic flows

Productivity Enhancers

  • Use Excel Import /Export to modify data externally and feed changes back into the tool
  • Use Batch Mode to automate frequent manual tasks using a fully customisable command file
  • Use the Statistics Wizard to run complex analysis algorithms over selected periods and export results to Excel for further analysis
  • Use the Scenario Transfer function to copy a user-defined scenario from one AIRAC cycle to another, capitalising on time spent preparing the initial scenario

SAAM Interoperability

The future for SAAM and NEVAC is one of ever closer integration. Substantial background work has allowed the two tools to communicate. The next phase will be user-driven, ensuring that users of both tools can exploit complementary functionalities seamlessly.

ACC Optimisation

NEVAC’s ICO algorithm generates an optimum opening scheme for given controller availabilities, configurations and sector/TV capacities. The optimisation, evaluated on a 10-minute sliding basis, balances tradeoffs defined in a customisable optimisation strategy. Minimum opening times and configuration continuity criteria are maintained while minimizing overloads and controller working hours. The result is an optimum series of sector opening times

ATFM Delay Simulation

NEVAC runs a static simulation of ATFM delays. It’s a one-shot process without any re-routing or dynamic re-adaptation of ACC configurations. An entire day of fixed flight trajectories, configuration opening schemes, capacities and regulations are fed into the model at the outset. Ground delays are then evaluated incrementally by pushing back flight takeoff times until all network capacity constraints are met.

Network Effect

The network effect can be modelled using NEVAC. It’s a phenomenon where regulations imposed on parts of the network affect the demand structure observed in other parts of the network. The network effect is important because there are structural limits within the network that modify the traffic handled by each ACC which need to be taken into account in capacity planning.

Future Traffic Samples

NEVAC’s FIPS algorithm generates future traffic samples using traffic growth forecasts provided by STATFOR. Today’s traffic is “grown” up to tomorrow’s levels using a random flight cloning process allowing airport capacities to constrain traffic growth. NEVAC data files are shipped with multiple STATFOR growth forecasts, which are used to provide a planning window of likely traffic

For more information on NEVAC

NEVAC has been developed in coordination with ANSPs and Flow management representatives from all countries within the ECAC zone. Special thanks go out to all the various contributors, whose feedback and ideas have been instrumental in the success of this NEVAC development.

If you would like more information, contact Stephanie Vincent or the NEVAC Project:
Mrs Stephanie Vincent
Capacity & Efficiency planning co-ordinator
NEVAC Project
The NEVAC Project Team

Research Activities

ASTAAC, a spin-off version of NEVAC, is currently used as a research validation platform by EUROCONTROL for prototyping and pre-evaluating advanced ATFCM concepts within the context of SESAR. Experimental functionalities are integrated alongside existing NEVAC functionalities, indeed in the past, as concepts and ideas have matured into robust technical solutions they have been diffused into the operational planning realm through the ECAC-wide NEVAC distribution network.

The broader aim now is to continue this partnership by maintaining a common core between the research validation and operational planning platforms. Thereby allowing users to continue to benefit from the NEVAC platform having one foot in the operational world and the other firmly planted in research activities.

ASTAAC Features

A sequencing algorithm has been developed in ASTAAC in order to pre-evaluate the SESAR concept of managing "Business Trajectories" using "Queue Management". This algorithm provides a series of time-target constraints to be respected. The delay absorption is managed in the airborne phase of the business trajectory and on the ground as a last resort.

A dynamic "Airspace Configuration" analysis algorithm has been developed in ASTAAC performing an analysis of traffic flows and running an airspace clustering process based on complexity.

If you would like more information on ASTAAC, please contact Françoise Guenin.
Mrs Françoise Guenin
Research Validation Infrastructure / ATFCM Tools co-ordinator
Last validation: 03/08/2009