Separately acquired intangible assets are initially recognised
at cost. Intangible assets acquired in a business combination
are recognised at their fair value at acquisition date. Acquired
intangible assets with fi nite useful lives are generally amortised on
a straight- line basis over their respective estimated useful lives
(3 to 10 years) to their estimated residual values. The amortisation
expense on intangible assets with fi nite lives is recognised in the
Consolidated Income Statement within the expense category
consistent with the function of the related intangible asset. The
amortisation method and the estimate of the useful lives of the
separately acquired intangible asset is reviewed at least annually
and changed if appropriate.aircraft production programmes such as the Airbus A380 with an
estimated number of aircraft to be produced using such tools, the
sum-of-the-units method effectively allocates the diminution of
value of specialised tools to the units produced. Property, plant
and equipment is derecognised when it has been disposed of or
when the asset is permanently withdrawn from use. The difference
between the net disposal proceeds and the carrying amount of
such assets is recognised in the Consolidated Income Statement
in the period of derecognition.