Note 4 — Inventory

The summary of inventories is as follows:

	August 31,		May 31,
	2014		2014
Raw materials and parts	$	100.5	$	114.1
Work-in-process	51.9		57.5
Aircraft and engine parts, components and finished goods	329.8		297.3
Aircraft held for sale and related support parts	49.8		26.4
	$	532.0	$	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 August 31, 2014, we had fifteen aircraft held for sale comprised of eight rotary-wing and seven fixed-wing aircraft. At May 31, 2014, we had nine aircraft held for sale comprised of five fixed-wing and four rotary-wing aircraft.