This excerpt taken from the AYR 8-K filed Sep 26, 2007.
Accounting for Income Taxes (SFAS No. 109). SFAS No. 109 requires an asset and liability based approach in accounting for income taxes. Deferred income tax assets and liabilities are recognized for the future tax consequences attributed to differences between the financial statement and tax basis of existing assets and liabilities using enacted rates applicable to the periods in which the differences are expected to affect taxable income. A valuation allowance is established when necessary to reduce deferred tax assets to the amount estimated by Aircastle to be realizable.