Summary of Significant Accounting Policies (Policies)	12 Months Ended
Feb. 28, 2021
Accounting Policies [Abstract]
Organization and Basis of Presentation	Aircastle Limited (“Aircastle,” the “Company,” “we,” “us” or “our”) is a Bermuda exempted company that was incorporated on October 29, 2004 under the provisions of Section 14 of the Companies Act of 1981 of Bermuda. Aircastle’s business is investing in aviation assets, including acquiring, leasing, managing and selling commercial jet aircraft.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Aircastle and all its subsidiaries. Aircastle consolidates two Variable Interest Entities (“VIEs”) of which Aircastle is the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation. We consolidate VIEs in which we have determined that we are the primary beneficiary. We use judgment when deciding (a) whether an entity is subject to consolidation as a VIE, (b) who the variable interest holders are, (c) the potential expected losses and residual returns of the variable interest holders, and (d) which variable interest holder is the primary beneficiary. When determining which enterprise is the primary beneficiary, we consider (1) the entity’s purpose and design, (2) which variable interest holder has the power to direct the activities that most significantly impact the entity’s economic performance, and (3) the obligation to absorb losses of the entity or the right to receive benefits from the entity that could potentially be significant to the VIE. When certain events occur, we reconsider whether we are the primary beneficiary of VIEs. We do not reconsider whether we are a primary beneficiary solely because of operating losses incurred by an entity.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. While Aircastle believes that the estimates and related assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents	Cash and Cash Equivalents and Restricted Cash and Cash Equivalents Aircastle considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents. Restricted cash and cash equivalents consist primarily of rent collections, maintenance payments and security deposits received from lessees pursuant to the terms of various lease agreements held in lockbox accounts in accordance with our financings. Virtually all our cash and cash equivalents and restricted cash and cash equivalents are held or managed by three major financial institutions.
Lessor, Leases [Policy Text Block]	Flight Equipment Held for Lease and Depreciation Flight equipment held for lease is stated at cost and depreciated using the straight-line method, typically over a 25-year life from the date of manufacture for passenger aircraft and over a 30 to 35-year life for freighter aircraft, depending on whether the aircraft is a converted or purpose-built freighter, to estimated residual values. Estimated residual values are generally determined to be approximately 15% of the manufacturer’s estimated realized price for passenger aircraft when new and 5% to 10% for freighter aircraft when new. Management may make exceptions to this policy on a case-by-case basis when, in its judgment, the residual value calculated pursuant to this policy does not appear to reflect current expectations of value. Examples of situations where exceptions may arise include but are not limited to: •flight equipment where estimates of the manufacturer’s realized sales prices are not relevant (e.g., freighter conversions); •flight equipment where estimates of the manufacturer’s realized sales prices are not readily available; and •flight equipment which may have a shorter useful life due to obsolescence. Major improvements and modifications incurred in connection with the acquisition of aircraft that are required to get the aircraft ready for initial service are capitalized and depreciated over the remaining life of the flight equipment. For planned major maintenance activities for aircraft off-lease, the Company capitalizes the actual maintenance costs by applying the deferral method. Under the deferral method, we capitalize the actual cost of major maintenance events, which are depreciated on a straight-line basis over the period until the next maintenance event is required. In accounting for flight equipment held for lease, we make estimates about the expected useful lives, the fair value of attached leases, acquired maintenance assets or liabilities and the estimated residual values. In making these estimates, we rely upon actual industry experience with the same or similar aircraft types and our anticipated lessee’s utilization of the aircraft. For purchase and lease back transactions, we account for the transaction as a single arrangement. We allocate the consideration paid based on the fair value of the aircraft and lease. The fair value of the lease may include a maintenance premium and a lease premium or discount. When we acquire an aircraft with a lease, determining the fair value of attached leases requires us to make assumptions regarding the current fair values of leases for specific aircraft. We estimate a range of current lease rates of like aircraft in order to determine if the attached lease is within a fair value range. If a lease is below or above the range of current lease rates, we present value the estimated amount below or above the fair value range over the remaining term of the lease. The resulting lease discount or premium is amortized into lease rental income over the remaining term of the lease. Lease Incentives and Amortization Many of our leases contain provisions which may require us to pay a portion of the lessee’s costs for heavy maintenance, overhaul or replacement of certain high-value components. We account for these expected payments as lease incentives, which are amortized as a reduction of revenue over the life of the lease. We estimate the amount of our portion for such costs, typically for the first major maintenance event for the airframe, engines, landing gear and auxiliary power units, expected to be paid to the lessee based on assumed utilization of the related aircraft by the lessee, the anticipated amount of the maintenance event cost and the estimated amounts the lessee is responsible to pay. The assumptions supporting these estimates are re-evaluated annually. This estimated lease incentive is not recognized as a lease incentive liability at the inception of the lease. We recognize the lease incentive as a reduction of lease revenue on a straight-line basis over the life of the lease, with the offset being recorded as a lease incentive liability which is included in maintenance payments on the balance sheet. The payment to the lessee for the lease incentive liability is first recorded against the lease incentive liability, and any excess above the lease incentive liability is recorded as a prepaid lease incentive asset, which is included in other assets on the balance sheet and continues to amortize over the remaining life of the lease. Lease acquisition costs related to reconfiguration of the aircraft cabin, other lessee specific modifications and other direct costs are capitalized and amortized into revenue over the initial life of the lease, assuming no lease renewals, and are included in other assets.
Impairment of Flight Equipment	Impairment of Flight Equipment We perform a recoverability assessment of all aircraft in our fleet, on an aircraft-by-aircraft basis annually during the second quarter. In addition, a recoverability assessment is performed whenever events or changes in circumstances, or indicators, suggest that the carrying amount or net book value of an asset may not be recoverable. Indicators may include, but are not limited to, a significant lease restructuring or early lease termination, significant change in aircraft model’s storage levels, the introduction of newer technology aircraft or engines, an aircraft type is no longer in production or a significant airworthiness directive is issued. When we perform a recoverability assessment, we measure whether the estimated future undiscounted net cash flows expected to be generated by the aircraft exceed its net book value. The undiscounted cash flows consist of cash flows from currently contracted lease rental and maintenance payments, future projected lease rates, transition costs, estimated down time, estimated residual or scrap values for an aircraft, economic conditions and other factors. In the event that an aircraft does not meet the recoverability test, the aircraft will be adjusted to fair value, resulting in an impairment charge. See Note 2 – Fair Value Measurements. Management develops the assumptions used in the recoverability analysis based on current and future expectations of the global demand for a particular aircraft type and historical experience in the aircraft leasing market and aviation industry, as well as information received from third party industry sources. The factors considered in estimating the undiscounted cash flows are impacted by changes in future periods due to changes in projected lease rental and maintenance payments, residual values, economic conditions, technology, airline demand for a particular aircraft type and other factors. We are closely monitoring the impact of COVID-19 on our customers, air traffic, lease rental rates, and aircraft valuations, and have and will continue to perform additional customer and aircraft specific reviews should changes in facts and circumstances arise that may impact the recoverability of our aircraft. We will focus on our customers that have entered judicial insolvency proceedings and any additional customers that may become subject to similar-type proceedings, aircraft with near-term lease expirations, and certain aircraft variants that are more susceptible to the impact of COVID-19 and value deterioration.
Net Investment in Finance Leases	Net Investment in Direct Financing and Sales-Type Leases If a lease meets specific criteria at lease commencement or at the effective date of a lease modification, we recognize the lease as a direct financing or sales-type lease. The net investment in direct financing and sales-type leases consists of the lease receivable, estimated unguaranteed residual value of the lease flight equipment at lease-end and, for direct financing leases, deferred selling profit. For sales-type leases, we recognize the difference between the net book value of the aircraft and the net investment in the lease as a gain or loss on sale of flight equipment. Selling profit on a direct financing lease is deferred and amortized over the lease term, and a selling loss is recognized at lease commencement. Interest income on our net investment in leases is recognized as Direct financing and sales-type leases revenue over the lease term in a manner that produces a constant rate of return on the net investment in the lease. The net investment in leases is recorded net of an allowance for credit losses. The allowance for credit losses is recorded upon the initial recognition of the net investment in the lease based on the Company’s estimate of expected credit losses over the lease term. The allowance reflects the Company’s estimate of lessee default probabilities and loss given default percentages. When determining the credit loss allowance, we consider relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the net investment in the lease. The allowance also considers potential losses due to non-credit risk related to unguaranteed residual values. A provision for credit losses is recorded as a component of Selling, general, and administrative expenses to adjust the allowance for changes to management’s estimate of expected credit losses.
Unconsolidated Equity Method Investment	Unconsolidated Equity Method InvestmentAircastle accounts for its interest in an unconsolidated joint venture using the equity method as we do not control the joint venture entity. Under the equity method, the investment is initially recorded at cost and the carrying amount is affected by its share of the unconsolidated joint venture’s undistributed earnings and losses, and distributions of dividends and capital.
Security Deposits	Security Deposits Most of our operating leases require the lessee to pay Aircastle a security deposit or provide a letter of credit. Security deposits represent cash received from the lessee that is held on deposit until lease expiration or termination. If a lease is terminated, we recognize security deposits in excess of outstanding lease payments as other revenue.
Maintenance Payments	Maintenance Payments Typically, under an operating lease, the lessee is responsible for performing all maintenance but they may also be required to make payments to us for heavy maintenance, overhaul or replacement of certain high-value components of the aircraft. These maintenance payments are based on hours or cycles of utilization or on calendar time, depending upon the component, and are required to be made monthly in arrears or at the end of the lease term. Whether to permit a lessee to make maintenance payments at the end of the lease term, rather than requiring such payments to be made monthly, depends on a variety of factors, including the creditworthiness of the lessee, the level of security deposit which may be provided by the lessee and market conditions at the time we enter into the lease. If a lease requires monthly maintenance payments, we would typically be obligated to reimburse the lessee for costs they incur for heavy maintenance, overhaul or replacement of certain high-value components to the extent of maintenance payments received in respect of the specific maintenance event, usually shortly following completion of the relevant work. If a lease requires end of lease term maintenance payments, typically the lessee would be required to pay us for its utilization of the aircraft during the lease; however, in some cases, we may owe a net payment to the lessee in the event heavy maintenance is performed and paid for by the lessee during the lease term and the aircraft is returned to us in better condition than at lease inception. We record monthly maintenance payments by the lessee as accrued maintenance payments liabilities in recognition of our contractual commitment to refund such receipts. In these contracts, we typically do not recognize such maintenance payments as maintenance revenue during the lease. Reimbursements to the lessee upon the receipt of evidence of qualifying maintenance work are charged against the existing accrued maintenance payments liability. We currently defer maintenance revenue recognition of most monthly maintenance payments until we are able to determine the amount, if any, by which the monthly maintenance payments received from a lessee exceed costs to be incurred by that lessee in performing heavy maintenance, which generally occurs at or near the end of the lease. End of lease term maintenance payments made to us are recognized as maintenance revenue, and end of lease term maintenance payments we make to a lessee are recorded as contra maintenance revenue.
Income Taxes	Income Taxes Aircastle uses 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 us to be realizable. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities. We did not have any unrecognized tax benefits.
Lease Revenue Recognition	Lease Revenue Recognition We lease flight equipment under net operating leases with lease terms typically ranging from three to seven years. We generally do not offer renewal terms or purchase options in our leases, although certain of our operating leases allow the lessee the option to extend the lease for an additional term. Operating leases with fixed rentals and step rentals are recognized on a straight-line basis over the term of the initial lease, assuming no renewals. Operating lease rentals that adjust based on a London Interbank Offered Rate (“LIBOR”) index are recognized on a straight-line basis over the lease term using the prevailing rate at lease commencement. Changes to rate-based lease rentals are recognized in the statements of income (loss) in the period of change. In certain instances, we may provide lease concessions to customers, generally in the form of lease rental deferrals. While these deferral arrangements affect the timing of lease rental payments, the total amount of lease rental payments required over the lease term is generally the same as that which was required under the original lease agreement. We account for the deferrals as if no modifications to the lease agreements were made and record the deferred rentals as a receivable within Other assets. If we determine that the collectability of rental payments is no longer probable (including any deferral thereof), we recognize lease rental revenue using a cash basis of accounting rather than an accrual method. In the period we conclude that collection of lease payments is no longer probable, we recognize any difference between revenue amounts recognized to date under the accrual method and payments that have been collected from the lessee, including security deposit amounts held, as a current period adjustment to lease rental revenue. COVID-19 has had an unprecedented negative impact on the global economy, and in particular on the aviation sector. As a result of COVID-19, there has been a dramatic slowdown in air traffic, with many markets in near complete shutdown. According to the International Air Transport Association (“IATA”), as of February 2021, air travel was down to approximately 30% of normal levels and a full recovery to pre-pandemic levels is not expected for several years. Substantially all the world’s airlines are experiencing financial difficulties and liquidity challenges. While we believe the long-term demand for air travel will return to historical trends over time, the near-term impacts of COVID-19’s economic shock are material; the extent and duration of which cannot currently be determined. Airlines have been seeking to preserve liquidity through a combination of requesting government support, raising debt and equity, delaying or canceling new aircraft orders, furloughing employees, as well as requesting deferrals from lessors. We have agreed to defer near-term lease payments with certain of our airline customers, which they are obliged to repay over time. As of April 15, 2021, we have agreed to defer approximately $108,400 in near-term lease payments of which approximately $87,400 are included in Accounts receivable or Other assets as of February 28, 2021. This represents approximately 17% of Lease rental and Direct financing and sales-type lease revenues for the twelve months ended February 28, 2021. These deferrals have been agreed to with 26 airlines, representing 35% of our customer base, for an average deferral of five months of lease rentals. In certain situations, we have agreed to broader restructurings of contractual terms, for example obtaining better security packages, term extensions, or other valuable considerations in exchange for short-term economic concessions. If air traffic remains depressed over an extended period and if our customers are unable to obtain sufficient funds from private, governmental or other sources, we may need to grant additional deferrals to our customers or extend the periods of repayment for deferrals we have already made. We may ultimately not be able to collect all the amounts we have deferred. As of April 15, 2021, seven of our customers are subject to judicial insolvency proceedings or similar protection. We lease 23 aircraft to these customers, which comprise 14% of our net book value of flight equipment (including Flight equipment held for lease and Net investment in leases) and 12% of our Lease rental and direct financing and sales-type lease revenue as of and for the year ended February 28, 2021. One of these customers is LATAM, our second largest customer, which represents 8% of our net book value of flight equipment and 6% of our Lease rental revenue as of and for the year ended February 28, 2021. Based on historic experience, the judicial process can take anywhere from twelve months to eighteen months to be resolved. We are actively engaged in the various judicial proceedings to protect our economic interests. As a result of these proceedings, the recognition of lease rental revenue for certain customers may be done on a cash basis of accounting rather than the accrual method depending on the customers lease security arrangements.
Comprehensive Income	Comprehensive Income (Loss) Comprehensive income (loss) consists of net income and other gains and losses, net of income taxes, if any, affecting shareholders’ equity that, under U.S. GAAP, are excluded from net income (loss).
Share Based Compensation	Share-Based Compensation Aircastle recognized compensation cost relating to share-based payment transactions in the financial statements based on the fair value of the equity instruments issued. Aircastle used the straight-line method of accounting for compensation cost on share-based payment awards that contained pro-rata vesting provisions.
Deferred Financing Costs	Deferred Financing Costs Deferred financing costs, which are included in borrowings from secured and unsecured financings, net of debt issuance costs, in the Consolidated Balance Sheets, are amortized using the interest method for amortizing loans over the lives of the relevant related debt.
Recent Unadopted Accounting Pronouncements	Recent Accounting Pronouncements In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848), Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The standard applies to entities that have contracts, such as debt agreements, lease agreements or derivative instruments, which reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. Entities can elect not to apply certain modification accounting requirements for contract modifications that replace a reference rate affected by reference rate reform. If elected, such contracts are accounted for as a continuation of the existing contract and no reassessments or re-measurements are required. The standard is effective for all entities from March 12, 2020 through December 31, 2022 and does not apply to contract modifications made after December 31, 2022. We have not adopted ASC 848 and are currently evaluating the election available to us under the standard and the impact it may have on our financial statements. In April 2020, the FASB Staff issued a question-and-answer document (the “Q&A”) regarding accounting for lease concessions related to the effects of the COVID-19 pandemic. The Q&A provides that entities may elect to apply or not apply the lease modification guidance in ASC 842, “Leases,” for lease concessions provided by lessors as a result of the COVID-19 pandemic. The Company has elected not to apply the lease modification guidance in ASC 842 for such lease concessions – see “Lease Revenue Recognition” above.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Feb. 28, 2021

Aircastle Limited (“Aircastle,” the “Company,” “we,” “us” or “our”) is a Bermuda exempted company that was incorporated on October 29, 2004 under the provisions of Section 14 of the Companies Act of 1981 of Bermuda. Aircastle’s business is investing in aviation assets, including acquiring, leasing, managing and selling commercial jet aircraft.

Principles of Consolidation

The consolidated financial statements include the accounts of Aircastle and all its subsidiaries. Aircastle consolidates two Variable Interest Entities (“VIEs”) of which Aircastle is the primary beneficiary. All intercompany transactions and balances have been eliminated in consolidation.

We consolidate VIEs in which we have determined that we are the primary beneficiary. We use judgment when deciding (a) whether an entity is subject to consolidation as a VIE, (b) who the variable interest holders are, (c) the potential expected losses and residual returns of the variable interest holders, and (d) which variable interest holder is the primary beneficiary. When determining which enterprise is the primary beneficiary, we consider (1) the entity’s purpose and design, (2) which variable interest holder has the power to direct the activities that most significantly impact the entity’s economic performance, and (3) the obligation to absorb losses of the entity or the right to receive benefits from the entity that could potentially be significant to the VIE. When certain events occur, we reconsider whether we are the primary beneficiary of VIEs. We do not reconsider whether we are a primary beneficiary solely because of operating losses incurred by an entity.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. While Aircastle believes that the estimates and related assumptions used in the preparation of the consolidated financial statements are appropriate, actual results could differ from those estimates.

Cash and Cash Equivalents, Restricted Cash and Cash Equivalents

Cash and Cash Equivalents and Restricted Cash and Cash Equivalents

Aircastle considers all highly liquid investments with maturities of three months or less when purchased to be cash equivalents.

Restricted cash and cash equivalents consist primarily of rent collections, maintenance payments and security deposits received from lessees pursuant to the terms of various lease agreements held in lockbox accounts in accordance with our financings.

Virtually all our cash and cash equivalents and restricted cash and cash equivalents are held or managed by three major financial institutions.

Lessor, Leases [Policy Text Block]

Flight Equipment Held for Lease and Depreciation

Flight equipment held for lease is stated at cost and depreciated using the straight-line method, typically over a 25-year life from the date of manufacture for passenger aircraft and over a 30 to 35-year life for freighter aircraft, depending on whether the aircraft is a converted or purpose-built freighter, to estimated residual values. Estimated residual values are generally determined to be approximately 15% of the manufacturer’s estimated realized price for passenger aircraft when new and 5% to 10% for freighter aircraft when new. Management may make exceptions to this policy on a case-by-case basis when, in its judgment, the residual value calculated pursuant to this policy does not appear to reflect current expectations of value. Examples of situations where exceptions may arise include but are not limited to:

•flight equipment where estimates of the manufacturer’s realized sales prices are not relevant (e.g., freighter conversions);

•flight equipment where estimates of the manufacturer’s realized sales prices are not readily available; and

•flight equipment which may have a shorter useful life due to obsolescence.

Major improvements and modifications incurred in connection with the acquisition of aircraft that are required to get the aircraft ready for initial service are capitalized and depreciated over the remaining life of the flight equipment.

For planned major maintenance activities for aircraft off-lease, the Company capitalizes the actual maintenance costs by applying the deferral method. Under the deferral method, we capitalize the actual cost of major maintenance events, which are depreciated on a straight-line basis over the period until the next maintenance event is required.

In accounting for flight equipment held for lease, we make estimates about the expected useful lives, the fair value of attached leases, acquired maintenance assets or liabilities and the estimated residual values. In making these estimates, we rely upon actual industry experience with the same or similar aircraft types and our anticipated lessee’s utilization of the aircraft.

For purchase and lease back transactions, we account for the transaction as a single arrangement. We allocate the consideration paid based on the fair value of the aircraft and lease. The fair value of the lease may include a maintenance premium and a lease premium or discount.

When we acquire an aircraft with a lease, determining the fair value of attached leases requires us to make assumptions regarding the current fair values of leases for specific aircraft. We estimate a range of current lease rates of like aircraft in order to determine if the attached lease is within a fair value range. If a lease is below or above the range of current lease rates, we present value the estimated amount below or above the fair value range over the remaining term of the lease. The resulting lease discount or premium is amortized into lease rental income over the remaining term of the lease.

Lease Incentives and Amortization

Many of our leases contain provisions which may require us to pay a portion of the lessee’s costs for heavy maintenance, overhaul or replacement of certain high-value components. We account for these expected payments as lease incentives, which are amortized as a reduction of revenue over the life of the lease. We estimate the amount of our portion for such costs, typically for the first major maintenance event for the airframe, engines, landing gear and auxiliary power units, expected to be paid to the lessee based on assumed utilization of the related aircraft by the lessee, the anticipated amount of the maintenance event cost and the estimated amounts the lessee is responsible to pay. The assumptions supporting these estimates are re-evaluated annually.

This estimated lease incentive is not recognized as a lease incentive liability at the inception of the lease. We recognize the lease incentive as a reduction of lease revenue on a straight-line basis over the life of the lease, with the offset being recorded as a lease incentive liability which is included in maintenance payments on the balance sheet. The payment to the lessee for the lease incentive liability is first recorded against the lease incentive liability, and any excess above the lease incentive liability is recorded as a prepaid lease incentive asset, which is included in other assets on the balance sheet and continues to amortize over the remaining life of the lease.

Lease acquisition costs related to reconfiguration of the aircraft cabin, other lessee specific modifications and other direct costs are capitalized and amortized into revenue over the initial life of the lease, assuming no lease renewals, and are included in other assets.

Impairment of Flight Equipment

We perform a recoverability assessment of all aircraft in our fleet, on an aircraft-by-aircraft basis annually during the second quarter. In addition, a recoverability assessment is performed whenever events or changes in circumstances, or indicators, suggest that the carrying amount or net book value of an asset may not be recoverable. Indicators may include, but are not limited to, a significant lease restructuring or early lease termination, significant change in aircraft model’s storage levels, the introduction of newer technology aircraft or engines, an aircraft type is no longer in production or a significant airworthiness directive is issued. When we perform a recoverability assessment, we measure whether the estimated future undiscounted net cash flows expected to be generated by the aircraft exceed its net book value. The undiscounted cash flows consist of cash flows from currently contracted lease rental and maintenance payments, future projected lease rates, transition costs, estimated down time, estimated residual or scrap values for an aircraft, economic conditions and other factors. In the event that an aircraft does not meet the recoverability test, the aircraft will be adjusted to fair value, resulting in an impairment charge. See Note 2 – Fair Value Measurements.

Management develops the assumptions used in the recoverability analysis based on current and future expectations of the global demand for a particular aircraft type and historical experience in the aircraft leasing market and aviation industry, as well as information received from third party industry sources. The factors considered in estimating the

undiscounted cash flows are impacted by changes in future periods due to changes in projected lease rental and maintenance payments, residual values, economic conditions, technology, airline demand for a particular aircraft type and other factors.

We are closely monitoring the impact of COVID-19 on our customers, air traffic, lease rental rates, and aircraft valuations, and have and will continue to perform additional customer and aircraft specific reviews should changes in facts and circumstances arise that may impact the recoverability of our aircraft. We will focus on our customers that have entered judicial insolvency proceedings and any additional customers that may become subject to similar-type proceedings, aircraft with near-term lease expirations, and certain aircraft variants that are more susceptible to the impact of COVID-19 and value deterioration.

Net Investment in Finance Leases

Net Investment in Direct Financing and Sales-Type Leases

If a lease meets specific criteria at lease commencement or at the effective date of a lease modification, we recognize the lease as a direct financing or sales-type lease. The net investment in direct financing and sales-type leases consists of the lease receivable, estimated unguaranteed residual value of the lease flight equipment at lease-end and, for direct financing leases, deferred selling profit. For sales-type leases, we recognize the difference between the net book value of the aircraft and the net investment in the lease as a gain or loss on sale of flight equipment. Selling profit on a direct financing lease is deferred and amortized over the lease term, and a selling loss is recognized at lease commencement. Interest income on our net investment in leases is recognized as Direct financing and sales-type leases revenue over the lease term in a manner that produces a constant rate of return on the net investment in the lease.

The net investment in leases is recorded net of an allowance for credit losses. The allowance for credit losses is recorded upon the initial recognition of the net investment in the lease based on the Company’s estimate of expected credit losses over the lease term. The allowance reflects the Company’s estimate of lessee default probabilities and loss given default percentages. When determining the credit loss allowance, we consider relevant information about past events, current conditions, and reasonable and supportable forecasts that affect the collectability of the net investment in the lease. The allowance also considers potential losses due to non-credit risk related to unguaranteed residual values. A provision for credit losses is recorded as a component of Selling, general, and administrative expenses to adjust the allowance for changes to management’s estimate of expected credit losses.

Unconsolidated Equity Method Investment

Unconsolidated Equity Method InvestmentAircastle accounts for its interest in an unconsolidated joint venture using the equity method as we do not control the joint venture entity. Under the equity method, the investment is initially recorded at cost and the carrying amount is affected by its share of the unconsolidated joint venture’s undistributed earnings and losses, and distributions of dividends and capital.

Security Deposits

Most of our operating leases require the lessee to pay Aircastle a security deposit or provide a letter of credit. Security deposits represent cash received from the lessee that is held on deposit until lease expiration or termination. If a lease is terminated, we recognize security deposits in excess of outstanding lease payments as other revenue.

Maintenance Payments

Typically, under an operating lease, the lessee is responsible for performing all maintenance but they may also be required to make payments to us for heavy maintenance, overhaul or replacement of certain high-value components of the aircraft. These maintenance payments are based on hours or cycles of utilization or on calendar time, depending upon the component, and are required to be made monthly in arrears or at the end of the lease term. Whether to permit a lessee to make maintenance payments at the end of the lease term, rather than requiring such payments to be made monthly, depends on a variety of factors, including the creditworthiness of the lessee, the level of security deposit which may be provided by the lessee and market conditions at the time we enter into the lease. If a lease requires monthly maintenance payments, we would typically be obligated to reimburse the lessee for costs they incur for heavy maintenance, overhaul

or replacement of certain high-value components to the extent of maintenance payments received in respect of the specific maintenance event, usually shortly following completion of the relevant work. If a lease requires end of lease term maintenance payments, typically the lessee would be required to pay us for its utilization of the aircraft during the lease; however, in some cases, we may owe a net payment to the lessee in the event heavy maintenance is performed and paid for by the lessee during the lease term and the aircraft is returned to us in better condition than at lease inception.

We record monthly maintenance payments by the lessee as accrued maintenance payments liabilities in recognition of our contractual commitment to refund such receipts. In these contracts, we typically do not recognize such maintenance payments as maintenance revenue during the lease. Reimbursements to the lessee upon the receipt of evidence of qualifying maintenance work are charged against the existing accrued maintenance payments liability. We currently defer maintenance revenue recognition of most monthly maintenance payments until we are able to determine the amount, if any, by which the monthly maintenance payments received from a lessee exceed costs to be incurred by that lessee in performing heavy maintenance, which generally occurs at or near the end of the lease. End of lease term maintenance payments made to us are recognized as maintenance revenue, and end of lease term maintenance payments we make to a lessee are recorded as contra maintenance revenue.

Income Taxes

Aircastle uses 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 us to be realizable. The Company recognizes the tax benefit from an uncertain tax position only if it is more likely than not that the tax position will be sustained on examination by the taxing authorities. We did not have any unrecognized tax benefits.

Lease Revenue Recognition

We lease flight equipment under net operating leases with lease terms typically ranging from three to seven years. We generally do not offer renewal terms or purchase options in our leases, although certain of our operating leases allow the lessee the option to extend the lease for an additional term. Operating leases with fixed rentals and step rentals are recognized on a straight-line basis over the term of the initial lease, assuming no renewals. Operating lease rentals that adjust based on a London Interbank Offered Rate (“LIBOR”) index are recognized on a straight-line basis over the lease

term using the prevailing rate at lease commencement. Changes to rate-based lease rentals are recognized in the statements of income (loss) in the period of change.

In certain instances, we may provide lease concessions to customers, generally in the form of lease rental deferrals. While these deferral arrangements affect the timing of lease rental payments, the total amount of lease rental payments required over the lease term is generally the same as that which was required under the original lease agreement. We account for the deferrals as if no modifications to the lease agreements were made and record the deferred rentals as a receivable within Other assets.

If we determine that the collectability of rental payments is no longer probable (including any deferral thereof), we recognize lease rental revenue using a cash basis of accounting rather than an accrual method. In the period we conclude that collection of lease payments is no longer probable, we recognize any difference between revenue amounts recognized to date under the accrual method and payments that have been collected from the lessee, including security deposit amounts held, as a current period adjustment to lease rental revenue.

COVID-19 has had an unprecedented negative impact on the global economy, and in particular on the aviation sector. As a result of COVID-19, there has been a dramatic slowdown in air traffic, with many markets in near complete shutdown. According to the International Air Transport Association (“IATA”), as of February 2021, air travel was down to approximately 30% of normal levels and a full recovery to pre-pandemic levels is not expected for several years. Substantially all the world’s airlines are experiencing financial difficulties and liquidity challenges. While we believe the long-term demand for air travel will return to historical trends over time, the near-term impacts of COVID-19’s economic shock are material; the extent and duration of which cannot currently be determined.

Airlines have been seeking to preserve liquidity through a combination of requesting government support, raising debt and equity, delaying or canceling new aircraft orders, furloughing employees, as well as requesting deferrals from lessors. We have agreed to defer near-term lease payments with certain of our airline customers, which they are obliged to repay over time. As of April 15, 2021, we have agreed to defer approximately $108,400 in near-term lease payments of which approximately $87,400 are included in Accounts receivable or Other assets as of February 28, 2021. This represents approximately 17% of Lease rental and Direct financing and sales-type lease revenues for the twelve months ended February 28, 2021. These deferrals have been agreed to with 26 airlines, representing 35% of our customer base, for an average deferral of five months of lease rentals. In certain situations, we have agreed to broader restructurings of contractual terms, for example obtaining better security packages, term extensions, or other valuable considerations in exchange for short-term economic concessions.

If air traffic remains depressed over an extended period and if our customers are unable to obtain sufficient funds from private, governmental or other sources, we may need to grant additional deferrals to our customers or extend the periods of repayment for deferrals we have already made. We may ultimately not be able to collect all the amounts we have deferred.

As of April 15, 2021, seven of our customers are subject to judicial insolvency proceedings or similar protection. We lease 23 aircraft to these customers, which comprise 14% of our net book value of flight equipment (including Flight equipment held for lease and Net investment in leases) and 12% of our Lease rental and direct financing and sales-type lease revenue as of and for the year ended February 28, 2021. One of these customers is LATAM, our second largest customer, which represents 8% of our net book value of flight equipment and 6% of our Lease rental revenue as of and for the year ended February 28, 2021. Based on historic experience, the judicial process can take anywhere from twelve months to eighteen months to be resolved. We are actively engaged in the various judicial proceedings to protect our economic interests. As a result of these proceedings, the recognition of lease rental revenue for certain customers may be done on a cash basis of accounting rather than the accrual method depending on the customers lease security arrangements.

Comprehensive Income

Comprehensive Income (Loss)

Comprehensive income (loss) consists of net income and other gains and losses, net of income taxes, if any, affecting shareholders’ equity that, under U.S. GAAP, are excluded from net income (loss).

Share Based Compensation

Share-Based Compensation

Aircastle recognized compensation cost relating to share-based payment transactions in the financial statements based on the fair value of the equity instruments issued. Aircastle used the straight-line method of accounting for compensation cost on share-based payment awards that contained pro-rata vesting provisions.

Deferred Financing Costs

Deferred financing costs, which are included in borrowings from secured and unsecured financings, net of debt issuance costs, in the Consolidated Balance Sheets, are amortized using the interest method for amortizing loans over the lives of the relevant related debt.

Recent Unadopted Accounting Pronouncements

Recent Accounting Pronouncements

In March 2020, the FASB issued ASU No. 2020-04, Reference Rate Reform (Topic 848), Facilitation of the Effects of Reference Rate Reform on Financial Reporting. The standard applies to entities that have contracts, such as debt agreements, lease agreements or derivative instruments, which reference LIBOR or another reference rate expected to be discontinued due to reference rate reform. Entities can elect not to apply certain modification accounting requirements for contract modifications that replace a reference rate affected by reference rate reform. If elected, such contracts are accounted for as a continuation of the existing contract and no reassessments or re-measurements are required. The standard is effective for all entities from March 12, 2020 through December 31, 2022 and does not apply to contract modifications made after December 31, 2022. We have not adopted ASC 848 and are currently evaluating the election available to us under the standard and the impact it may have on our financial statements.

In April 2020, the FASB Staff issued a question-and-answer document (the “Q&A”) regarding accounting for lease concessions related to the effects of the COVID-19 pandemic. The Q&A provides that entities may elect to apply or not apply the lease modification guidance in ASC 842, “Leases,” for lease concessions provided by lessors as a result of the COVID-19 pandemic. The Company has elected not to apply the lease modification guidance in ASC 842 for such lease concessions – see “Lease Revenue Recognition” above.