AIC for PORTUGAL

 — IMPLEMENTATION OF ATS ROUTES UN741 AND UN866 AS UNIDIRECTIONAL ROUTES

The EUR-SAM Corridor connects the air traffic flows between Europe and South America.
Adapting to the air traffic necessities, the Corridor has been in constant evolution since its implementation. Currently the Corridor consists of four bi-directional airways and one Random routing where RVSM and RNP10 capabilities are required.

The radar surveillance through the EUR-SAM Corridor is very limited due to the huge distances across the Atlantic Ocean. In these circumstances the ATC has to provide air traffic separation minima based on procedural control techniques, the effect of these techniques is a much extended separation between aircraft that totally constrains the capacity of the ATC system, the optimum flight level allocation and the ATC to handle with the foreseen air traffic increases for next years.

Conscious of this situation, and as a previous and urgent measure before the implementation of the Regional Implementation Plan of RNP 4 in the Corridor, the International Civil Aviation Organization, ICAO, has endorsed SAT States to develop studies to put forward short term actions to minimize the negative effects described above.

In the aim to solve the problem, some operational and safety studies have been carried out during the last year. As a result of these studies, the best option to improve the ATC capacity and the management of optimum flight level allocation, maintaining the safety requirements of the EUR-SAM Corridor, is to designate RNAV RNP 10 the ATS Routes UN741 and UN866 as unidirectional routes using, in both of them ODD and EVEN flight levels with RVSM criteria of vertical separation.

UN741 route will be declared as unidirectional South bound routing from NELSO fix point using ODD and EVEN flight levels. Atlantic ACC over its airspace will be responsible for the allocation of the transferred south bound traffic at ODD flight levels to the suitable flight level according to their forward route.

UN866 route will be declared as unidirectional Northbound routing from BCO VOR fix point using ODD and EVEN flight levels. Canaries ACC, over its airspace, will be responsible for the allocation of the transferred northbound traffic at ODD flight levels to EVEN flight levels.

This new routing structure fro the EUR-SAM Corridor implies that the States must achieve complementary tasks as airspace re-organization, new connecting airways with Corridor, definition of new fix points, including this new structure in their respective AIP. This new routing structure of the Corridor will be implemented on AIRAC date July 5th 2007.