NORTH ATLANTIC - HEIGHT DEVIATION REPORT At its 27th meeting, the North Atlantic Systems Planning Group (NAT SPG) agreed that it was necessary to improve the effectiveness of the monitoring of height-keeping performance in the North Atlantic NAT) Region. In order to achieve this objective, NAT SPG tasked NAT Provider States with improving, where necessary, the effectiveness of reporting of height deviations to the Central Monitoring Agency (CMA). In turn, the CMA is required to initiate an investigation into the causes of reported height deviations. Please find attached details of a report of a height deviation in the NAT Region attributed to an aircraft registered in your State. I would be grateful if you would arrange for the circumstances of this incident to be investigated and advise this office of the causes of the reported deviation from the aircraft's cleared flight level, together with any remedial action you will betaking. Yours faithfully, NAT CMA for ICAO
