All aircraft activities that take place at altitudes above 914 meters (3.000 feet), including any additional climb or descent operations above this altitude. No upper limit is given.
(IPCC 2006, "Guidelines for National Greenhouse Gas Inventories", Volume 2: Energy, Ch3)
Illustration of the different flight phases
(EMEP/CORINAIR 2006, Emission inventory guidebook, Group 8: Other mobile sources and machinery)
=> Glossary