EUROCONTROL MSAW Specification and Guidance Material

EUROCONTROL MSAW Specification and Guidance Material


MSAW (Minimum Safe Altitude Warning) warns the controller about increased risk of Controlled Flight Into Terrain (CFIT) accidents by generating, in a timely manner, an alert of aircraft proximity to terrain or obstacles.

Since 1998, EUROCONTROL has produced safety net guidelines to support the implementation of safety nets in the European Civil Aviation Conference (ECAC) area. These specify the minimum requirements and provide guidance for the definition, implementation, optimisation and operation of ground-based safety nets. This article provides references to EUROCONTROL Minimum Safe Altitude Warning (MSAW) Specification and Guidance Material. Links to the articles about the other safety nets can be found at the bottom of this page.

EUROCONTROL MSAW Specification and Guidance Material has been developed over the years by the safety nets community based on the accumulated practical experience.

EUROCONTROL MSAW ‘Level 2’ Specification and Guidance Material

The EUROCONTROL MSAW Specification describes the minimum requirements for the development, configuration and use of MSAW in Europe. The Specification exists only as the final draft version while the Guidance Material has a ‘released’ status. Currently, there is no plan to undertake any further development of the Specification.

EUROCONTROL Specification for Minimum Safe Altitude Warning Draft

Comprehensive guidance material to assist in implementing the EUROCONTROL Specification for Minimum Safe Altitude Warning covers the full MSAW lifecycle:

  • Definition of objectives
  • Implementation or change
  • Tuning and validation
  • Operation and monitoring

The MSAW Guidance is provide with several appendices to support ANSPs in the implementation of MSAW.

EUROCONTROL Guidance Material for Minimum Safe Altitude Warning Released

Appendix A: Reference MSAW System: Detailed technical explanation of typical implementation details of MSAW with emphasis on parameterisation and performance optimisation. Optimisation concepts are also covered in detail.

Appendix B: Safety Assurance: A set of three documents that can be used as starting point for MSAW safety assurance work in a particular local context.

Appendix C: Cost Framework:

Appendix D: Case Study: A set of two documents describing the (partial) application of the optimisation and safety assurance guidance material in a demanding environment.

EUROCONTROL MSAW ‘Level 3’ Documentation

The ‘Level 3’ material, published in 2017, is a series of documents specifying the minimum requirements and providing guidance for the definition, implementation, optimisation and operation of safety nets. These guidelines, building on the legacy of the previous two editions, are intended to facilitate the harmonisation of safety nets by providing recommendations and implementation examples.

It is important to note that the ‘Level 3’ documents are guidelines as opposed to the mandatory ‘Level 2’ Specifications they replace. This allows ANSPs to adopt a more flexible approach towards implementing safety nets that meets their needs. The guidelines also complements other recognised documentation such as International Civil Aviation Organisation (ICAO) provisions.

Part I - Concept and Requirements - describes the safety net concept of operations and requirements.

Part II - Lifecycle Description - contains overall guidance for the various stages of the safety nets lifecycle.

Part III - Implementation and Optimisation Examples - provides a generic implementation example and detailed guidance for optimisation and testing of that safety net.

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