Note 5 — Inventory

The summary of inventories is as follows:

	February 28,		May 31,
	2015		2014
Raw materials and parts	$	41.7	$	114.1
Work-in-process	19.4		57.5
Aircraft and engine parts, components and finished goods	359.6		297.3
Aircraft held for sale and related support parts	30.3		26.4
	$	451.0	$	495.3

We classify certain aircraft from our expeditionary airlift business as assets held for sale at the time management commits to a plan to sell the aircraft, changes to the planned sale are not likely, the aircraft are actively marketed and available for immediate sale, and the sale is expected to be completed within one year. Upon designation of an aircraft as held for sale, we record the aircraft’s value at the lower of its carrying value or its estimated fair value, less estimated costs to sell. Assets held for sale are not depreciated.

Aircraft may be classified as assets held for sale for more than one year as we continue to actively market the aircraft at reasonable prices. Certain aircraft types we currently have available for sale are specifically designed for particular functions which limits the marketability of those assets. At February 28, 2015, we had 12 aircraft held for sale comprised of eight fixed-wing and four rotary-wing aircraft. At May 31, 2014, we had nine aircraft held for sale comprised of five fixed-wing and four rotary-wing aircraft. During the three-month period ended February 28, 2015, we recognized an impairment charge of $4.7 million reflecting the decrease in fair value for five fixed-wing aircraft held for sale and related rotable assets.