Ian Clark is a partner in aviation law firm Clark Ricketts – the firm was incorrectly named Clark Richards in The Lawyer, 22 July 1997.

Harmonisation of aviation regulation in Europe is well advanced. The European Economic Area (EEA) and member states are standardising aspects of their flight rules.

On 1 April 1997 the final phase of the "European Third Package" on the liberalisation of air transport was implemented. Now, every European airline is entitled to exercise "traffic rights" throughout the EEA. No approval need be sought by an air carrier to conduct public transport flights in another EEA host country.

However, the recent case of H5 Air Service Norway ApS v CAA raised an important question on the extent to which the residual powers of host states affect the exercising of these new traffic rights.

On 7 June 1997, the CAA "grounded" H5's Cessna C208 aircraft at Edinburgh Airport. H5 made an application to the High Court for an injunction against the CAA. Mr Justice Creswell declined to give an injunction, but ordered the urgent trial of the central issue. The case came before Mr Justice Thomas on 10 June. H5 held the necessary licences issued by the Norwegian Civil Aviation Authority permitting it to operate its Cessna C208 aircraft for the commercial carriage of cargo. The question was whether it was thereby entitled to operate such flights in the UK at night.

The Cessna C208 is a single-engine aircraft, and the UK does not permit UK-registered single-engined aircraft to be used for commercial cargo carrying. Neither does it grant "traffic rights" to non-EEA air carriers for use of single engine aircraft for public transport at night. H5 argued that, by holding a Norwegian licence, it was entitled, under Council Regulation (EEC) No.2408/92, to exercise traffic rights in the UK without needing approval. The UK CAA conceded there is no prohibition in UK legislation which prevents foreign registered single-engine aircraft carrying cargo commercially at night in the UK. But under Norwegian law, H5's operating licence is subject to the observance of local laws, regulations and procedures, and the UK CAA argued that this includes the UK's general opposition to the use of single-engined aircraft for cargo carrying at night.

Justice Thomas decided that, despite a lacuna in the UK regulations, its general opposition constituted a "procedure" that the Norwegian air carrier must observe. The decision is being appealed by H5.