Summary of Significant Accounting Policies

3 Months Ended

Dec. 31, 2024

Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America ("GAAP") and include the accounts of the Company and its wholly owned operating subsidiaries. Any reference in these notes to applicable guidance is meant to refer to the authoritative United States generally accepted accounting principles as found in the Accounting Standards Codification ("ASC") and Accounting Standards Update ("ASU") of the Financial Accounting Standards Board ("FASB"). All intercompany accounts and transactions have been eliminated in consolidation.

The consolidated financial statements have been prepared assuming the Company will continue as a going concern. The going concern assumption contemplates the realization of assets and satisfaction of liabilities in the normal course of business. The Company generated a net loss of $111.9 million and had cash flow used in operations of $11.6 million for the three months ended December 31, 2024. As of December 31, 2024, the Company had a working capital deficit of $92.0 million, an accumulated deficit of $274.1 million, and cash and cash equivalents of $40.0 million. The Company's strategic and financial plans outlined under Liquidity and Going Concern, specifically the Merger, will allow the Company to obtain required funding for future operations and obligations.

Use of Estimates

The preparation of the Company's consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, revenues, and expenses and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements. Actual results could differ from those estimates.

Segment Reporting

Operating segments are defined as components of an enterprise about which separate financial information is available that is evaluated regularly by the chief operating decision maker in deciding how to allocate resources and in assessing operating performance. In consideration of ASC 280, "Segment Reporting," we are not organized around specific services or geographic regions. We currently operate in one service line providing scheduled flying services in accordance with our CPA.

While we operate under our CPA, we do not manage our business based on any performance measure at the individual contract level. As of December 31, 2024, our chief operating decision maker ("CODM") was the Chief Executive Officer. Our CODM uses consolidated financial information to evaluate our performance, which is the same basis on which he communicates our results and performance to our Board of Directors. Our CODM bases all significant decisions regarding the allocation of our resources on a consolidated basis. Based on the information described above and in accordance with the applicable literature, management has concluded that we are organized and operated as one operating and reportable segment.

Cash and Cash Equivalents

The Company considers all highly liquid investments with an original maturity of three months or less when purchased to be cash equivalents.

Restricted Cash

Restricted cash primarily includes deposits in trust accounts to collateralize letters of credit and to fund workers' compensation claims, landing fees, and other business needs. Restricted cash is stated at cost, which approximates fair value.

The Company has an agreement with a financial institution for a $6.0 million letter of credit facility to issue letters of credit for landing fees, workers' compensation insurance, and other business needs. Pursuant to such agreement, $3.0 million, $3.0 million, and $3.1 million of outstanding letters of credit are required to be collateralized by amounts on deposit as of December 31, 2024 and September 30, 2024 and 2023, respectively, which are classified as restricted cash.

Cash, cash equivalents and restricted cash consist of the following:


	December 31,		September 30,
	2024		2024		2023
Cash and cash equivalents	$	39,980	$	15,621	$	32,940
Restricted cash		3,004		3,009		3,132
Total cash, cash equivalents and restricted cash	$	42,984	$	18,630	$	36,072

Expendable Parts and Supplies

Expendable parts and supplies are stated at cost, less an allowance for obsolescence. The Company provides an allowance for obsolescence for such parts and supplies over the useful life of its aircraft after considering the useful life of each aircraft fleet, the estimated cost of expendable parts expected to be on hand at the end of the useful life, and the estimated salvage value of the parts. This allowance for

expendable parts account was $4.7 million, $4.7 million, and $4.1 million as of December 31, 2024 and September 30, 2024 and 2023, respectively.

Property and Equipment

Property and equipment are stated at cost, net of manufacturer incentives, and depreciated over their estimated useful lives to their estimated salvage values, which are 20% for aircraft and rotable spare parts, using the straight-line method.

Estimated useful lives of the various classifications of property and equipment are as follows:


Property and Equipment		Estimated Useful Life
Buildings		30 years
Aircraft		25 years from the manufacture date
Flight equipment		7-20 years
Equipment		5-9 years
Furniture and fixtures		3-5 years
Vehicles		5 years
Rotable spare parts		Life of the aircraft or term of the lease, whichever is less
Leasehold improvements		Life of the aircraft or term of the lease, whichever is less

Long-lived assets to be held and used are reviewed for impairment whenever events or changes in circumstances indicate that the related carrying amount may be impaired. The Company records an impairment loss if (i) the undiscounted future cash flows are found to be less than the carrying amount of the asset or asset group, and (ii) the carrying amount of the asset or asset group exceeds its fair value. If an impairment loss has occurred, a charge is recorded to reduce the carrying amount of the asset to its estimated fair value.

To determine whether impairments exist for aircraft and other related assets used in operations, we group assets at the CPA level (i.e., the lowest level for which there are identifiable cash flows) and then estimate future cash flows based on projections of capacity purchase block hours, maintenance events, labor costs and other relevant factors. If an asset group is impaired, the impairment loss recognized is the amount by which the asset group's carrying amount exceeds its estimated fair value. We estimate aircraft fair values using published sources, appraisals and bids received from third parties, as available. Due to the sales price of our E-175 aircraft pursuant to the Aircraft Purchase Agreement with United, $60.7 million of impairment was recorded to our fleet during the three months ended December 31, 2024. The Company did not record impairment expenses to our fleet during the fiscal years ended September 30, 2024 and 2023. The Company recognized $109.7 million in impairment on property and equipment and other long-lived assets for the fiscal year ended September 30, 2022.

Assets Held for Sale

We classify assets as held for sale when (i) our management approves and commits to a formal plan of sale that is probable of being completed within one year; (ii) the asset is available for immediate sale in its present condition subject only to terms that are usual and customary for sales of such assets; (iii) an active program to locate a buyer has been initiated; (iv) the asset is being actively marketed for sale at a price that is reasonable in relation to its current fair value; and (v) actions required to complete the plan indicate that it is unlikely that significant changes to the plan will be made or the plan will be withdrawn. Assets designated as held for sale are recorded at the lower of their current carrying value or their fair market value, less costs to sell, beginning in the period in which the assets meet the criteria to be classified as held for sale. If the market value, less costs to sell, is lower than the current carrying value, an impairment loss is recorded on the asset designated as held for sale. The Company recognized impairment expenses on assets designated as held for sale of $4.9 million and $40.4 million for the three months ended December 31, 2024 and 2023, respectively, and $73.7 million, $50.6 million, and $62.1 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively. See Note 6 – “Assets Held for Sale” for further discussion of our assets classified as held for sale as of December 31, 2024

Fair Value Measurements

The Company accounts for assets and liabilities in accordance with accounting standards that define fair value and establish a consistent framework for measuring fair value on either a recurring or a nonrecurring basis. Fair value is an exit price representing the amount that would be received to sell an asset, or paid to transfer a liability, in an orderly transaction between market participants. As such, fair value is a market-based measurement that should be determined based on assumptions that market participants would use in pricing an asset or liability.

Accounting standards include disclosure requirements relating to the fair values used for certain financial instruments and establish a fair value hierarchy. The hierarchy prioritizes valuation inputs into three levels based on the extent to which inputs used in measuring fair value are observable in the market. Each fair value measurement is reported in one of three levels:

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Level 1 – Observable inputs such as quoted prices in active markets for identical assets or liabilities;

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Level 2 – Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and

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Level 3 – Unobservable inputs in which there is little or no market data, requiring an entity to develop its own assumptions.

Debt Financing Costs

Debt financing costs consist of payments made to issue debt related to the purchase of aircraft, flight equipment, and certain flight equipment maintenance costs. The Company defers the costs and amortizes them to interest expense over the term of the debt agreement. Debt financing costs related to a recognized debt liability are presented as a direct deduction from the carrying amount of the related long-term debt on the consolidated balance sheet.

Other Assets

Other noncurrent assets primarily consist of a contract asset related to the issuance of equity to United as part of the United CPA. Upon entering into the United CPA and issuing equity to United, the Company recorded the contract asset at fair value of the shares issued to United. The contract asset is amortized as a reduction of revenue over the term of the CPA.

Lease incentives represent amounts paid or payable by Mesa to the lessee and are amortized as a reduction of lease revenue over the term of the lease. The current portion of the lease incentive assets is included in prepaid expenses and other current assets, and the non-current portion is included in other assets on the consolidated balance sheet.

Investments in equity securities with readily determinable fair values are adjusted to reflect the market value of the investments each reporting period, with corresponding gains and losses reflected in the statement of operations. Investments in equity securities without readily determinable values are measured at cost less impairment, if any, and are adjusted when there are observable prices of similar or identical investments from the same issuer.

Income Taxes

Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in future years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company records deferred tax assets for the value of benefits expected to be realized from the utilization of state and federal net operating loss carryforwards. The Company periodically reviews these assets to determine the likelihood of realization. To the extent the Company believes some portion of the benefit may not be realizable based on the available sources of income, an estimate of the unrealized position is made, and a valuation allowance is recorded. The Company and its consolidated subsidiaries file a consolidated federal income tax return.

Other Noncurrent Liabilities

Other noncurrent liabilities primarily consist of the non-current portion of lease incentive obligations and deposits related to the aircraft which Mesa leases to third parties and vendor credit liabilities for future purchases of electric aircraft.

Revenue Recognition

The Company recognizes revenue when the service is provided under its CPA. Under the CPA, United generally pays a fixed monthly minimum amount per aircraft, plus certain additional amounts based upon the number of flights and block hours flown. The contract also includes reimbursement of certain costs incurred by the Company in performing flight services. These costs, known as "pass-through costs," may include passenger liability insurance as well as aircraft property taxes and other flight service expenditures defined in our agreement. Additionally, for the E-175 aircraft owned by United, the CPA provides that United will reimburse the Company for heavy airframe and engine maintenance, landing gear, APUs and component maintenance. The Company also receives compensation under its CPA for heavy maintenance expenses at a fixed hourly rate or per aircraft rate for all aircraft in scheduled service other than the E-175 aircraft owned by United. The Company is eligible to receive incentive compensation upon the achievement of certain performance criteria defined in the agreement. At the end of each period during the term of an agreement, the Company calculates the incentives achieved during that period and recognizes revenue attributable to the agreement during the period accordingly, subject to the variable constraint guidance under ASC 606. All revenue recognized under the CPA is presented as the gross amount billed to United. Due to United's ownership in the Company (9.8% as of December 31, 2024), revenue recognized under the United CPA is considered related party revenue.

Under the United CPA, the Company has committed to perform various activities that can be generally classified into in-flight services and maintenance services. When evaluating these services, the Company determined that the nature of its promise is to provide a single integrated service, flight services, because its contracts require integration and assumption of risk associated with both services to effectively deliver and provide the flights as scheduled over the contract term. Therefore, the in-flight services and

maintenance services are inputs to that combined integrated flight service. Both services occur over the term of the agreement and the performance of maintenance services significantly affects the utility of the in-flight services. The Company's individual flights flown under the CPA are deemed to be distinct and the flight service promised in the CPA represents a series of services that is accounted for as a single performance obligation. This single performance obligation is satisfied over time as the flights are completed. Therefore, revenue is recognized when each flight is completed.

In allocating the transaction price, variable payments (i.e., billings based on flights and block hours flown, pass-through costs, etc.) that relate specifically to the Company's efforts in performing flight services are recognized in the period in which the individual flight is completed. The Company has concluded that allocating the variability directly to the individual flights results in an overall allocation meeting the objectives in ASC 606. This results in a pattern of revenue recognition that follows the variable amounts billed from the Company to their customers.

A portion of the Company's compensation under its CPAs with United and previously American is designed to reimburse the Company for certain aircraft ownership costs. The Company has concluded that a component of its revenue under these agreements is deemed to be lease revenue, as such agreements identify the "right of use" of a specific type and number of aircraft over a stated period-of-time. The lease revenue associated with the Company's CPA is accounted for as an operating lease and is reflected as contract revenue on the Company's consolidated statements of operations and comprehensive loss. The Company recognized $20.2 million, $34.9 million, $123.0 million, $144.7 million, and $158.4 million of lease revenue for the three months ended December 31, 2024 and 2023 and fiscal years ended September 30, 2024, 2023, and 2022, respectively. The Company has not separately stated aircraft rental income and aircraft rental expense in the consolidated statements of operations and comprehensive loss because the use of the aircraft is not a separate activity of the total service provided.

The Company's CPA is renewable periodically and contain provisions pursuant to which the parties could terminate their respective agreements, subject to certain conditions, as described in Note 1. The CPA also contains terms with respect to covered aircraft, services provided, and compensation as described in Note 1. The CPA is amended from time to time to change, add, or delete terms of the agreements.

The Company's revenues could be impacted by a number of factors, including amendment or termination of its CPA, contract modifications resulting from contract renegotiations, its ability to earn incentive payments contemplated under applicable agreements, and settlement of reimbursement disputes with United. In the event contracted rates are not finalized at a quarterly or annual financial statement date, the Company evaluates the enforceability of its contractual terms and when it has an enforceable right, it estimates the amount the Company expects to be entitled subject to the variable constraint guidance under ASC 606.

The Company records deferred revenue when cash payments are received or are due from United in advance of the Company’s performance. The deferred revenue balance as of December 31, 2024 of $15.3 million (current and non-current portion) represents our aggregate remaining performance obligations that will be recognized as revenue over the period in which the performance obligations are satisfied (as flights are completed over the remaining contract term). Deferrals of revenue and recognition of previously deferred revenue during the three months ended December 31, 2024 are shown below:


	Revenue Deferred/(Recognized)
Deferred revenue as of September 30, 2024	$	9,639
Fixed revenue deferrals		9,287
Pass-through revenue deferrals		2,858
Previously deferred fixed revenue recognized		(5,271	)
Previously deferred pass-through revenue recognized		(1,229	)
Deferred revenue as of December 31, 2024	$	15,284

Contract Liabilities

Contract liabilities consist of deferred credits representing upfront payments received from United related to aircraft modifications associated with the CPA and pilot training. The deferred credits are recognized over time depicting the pattern of transfer of the related services over the term of the CPA.

Current and non-current deferred credits are recorded to other accrued expenses and non-current deferred credits in the consolidated balance sheets, respectively. The Company's total current and non-current deferred credit balances at December 31, 2024 and September 30, 2024 and 2023 were $3.1 million, $4.1 million, and $5.1 million, respectively. The Company recognized $1.0 million and $1.0 million of the deferred credits within contract revenue in the consolidated statements of operations and comprehensive loss during the three months ended December 31, 2024 and 2023, respectively, and $1.8 million, $1.7 million, and $0.9 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively.

Contract Assets

The Company recognizes assets from the incremental costs incurred to obtain contracts with major partners including aircraft painting, aircraft reconfiguration, flight service personnel training costs, and the issuance of stock. These costs are amortized based on the pattern of transfer of the services in relation to flight hours over the term of the contract. Contract assets are recorded as other assets in the consolidated balance sheets. The Company's contract assets balance at December 31, 2024 and September 30, 2024 and 2023 was approximately $5.4 million, $6.1 million, and $8.8 million, respectively. Contract cost amortization was approximately $0.7 million and $0.4 million for the three months ended December 31, 2024 and 2023, respectively, and $2.7 million, $1.0 million, and $0 for the fiscal years ended September 30, 2024, 2023, and 2022, respectively.

Maintenance Expense

The Company operates under an FAA approved continuous inspection and maintenance program. The cost of non-major scheduled inspections and repairs and routine maintenance costs for all aircraft and engines are charged to maintenance expense as incurred.

The Company accounts for heavy maintenance and major overhaul costs on its owned E-175 fleet under the deferral method whereby the cost of heavy maintenance and major overhaul is deferred and amortized until the earlier of the end of the useful life of the related asset or the next scheduled heavy maintenance event. Amortization of heavy maintenance and major overhaul costs charged to depreciation and amortization expense was approximately $1.1 million and $0.8 million for the three months ended December 31, 2024 and 2023, respectively, and $3.2 million, $3.1 million, and $1.9 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively. At December 31, 2024 and September 30, 2024 and 2023, the Company had a deferred heavy maintenance balance, net of accumulated amortization, of approximately $5.4 million, $6.4 million, and $8.0 million, respectively. The Company accounts for heavy maintenance and major overhaul costs for all other fleets under the direct expense method whereby costs are expensed to maintenance expense as incurred, except for certain maintenance contracts where labor and materials price risks have been transferred to the service provider and require payment on a utilization basis, such as flight hours. Costs incurred for maintenance and repair for utilization maintenance contracts where labor and materials price risks have been transferred to the service provider are charged to maintenance expense based on contractual payment terms. Our maintenance policy is determined by fleet when major maintenance is incurred.

Under the Company's aircraft operating lease agreements and FAA operating regulations, it is obligated to perform all required maintenance activities on its fleet, including component repairs, scheduled airframe checks and major engine restoration events. The Company estimates the timing of the next major maintenance event based on assumptions including estimated usage, FAA-mandated maintenance intervals, and average removal times as recommended by the manufacturer. The timing and the cost of maintenance are based on estimates, which can be impacted by changes in utilization of its aircraft,

changes in government regulations and suggested manufacturer maintenance intervals. Major maintenance events consist of overhauls to major components.

Engine overhaul expense totaled approximately $10.1 million and $5.8 million for the three months ended December 31, 2024 and 2023, respectively, of which approximately $10.1 million and $5.7 million, respectively, was pass-through expense. Engine overhaul expense totaled approximately $23.0 million, $32.4 million, and $23.6 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively, of which approximately $23.5 million, $31.9 million, and $21.7 million, respectively, was pass-through expense. The Company received approximately $0.5 million from an insurance claim reimbursement during fiscal year 2024 which was net against engine overhaul expense. Airframe C-check expense totaled approximately $8.4 million and $6.4 million for the three months ended December 31, 2024 and 2023, respectively, of which approximately $7.7 million and $3.8 million, respectively, was pass-through expense. Airframe C-check expense totaled approximately $22.9 million, $23.4 million, and $22.1 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively, of which approximately $16.3 million, $16.9 million, and $3.2 million, respectively, was pass-through expense.

Pursuant to the United CPA, United reimburses the Company for heavy maintenance on certain E-175 aircraft. Those reimbursements are included in pass-through and other revenue. See Note 1 - "Organization and Operations" for further information.

Leases

We determine if an arrangement is a lease at inception. As a lessee, we have lease agreements with lease and non-lease components and have elected to account for such components as a single lease component. Our operating lease activities are recorded in operating lease right-of-use assets, current maturities of operating leases, and noncurrent operating lease liabilities in the consolidated balance sheets. Finance leases are reflected in property and equipment, net, current portion of long-term debt and finance leases, and long-term debt and finance leases, excluding current portion in the consolidated balance sheets.

Right-of-use ("ROU") assets represent our right to use an underlying asset for the lease term and lease liabilities represent our obligation to make lease payments arising from the lease. Operating lease ROU assets and liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. Variable lease payments are not included in the calculation of the right-of-use assets and lease liability due to uncertainty of the payment amount and are recorded as lease expense in the period incurred. As most of our leases do not provide an implicit rate, we use our estimated incremental borrowing rate based on the information available at the lease commencement date in determining the present value of lease payments. We use the implicit rate when readily determinable. Our lease terms may include options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Operating lease costs are recognized on a straight-line basis over the lease term, while finance leases result in a front-loaded expense pattern.

To determine whether impairments exist for aircraft and other related assets used in operations, we group assets, including ROU assets, at the CPA level (i.e., the lowest level for which there are identifiable cash flows) and then estimate future cash flows based on projections of capacity purchase block hours, maintenance events, labor costs and other relevant factors. As all of our aircraft leases besides short-term aircraft leases are leased to us from United at nominal amounts and not recorded on our books, we did not assess leased aircraft for impairment. The Company recorded impairment losses of $60.7 million and $0 for the three months ended December 31, 2024 and 2023, respectively, and recorded impairment losses of $0, $0, and $10.5 million for the fiscal years ended September 30, 2024, 2023, and 2022, respectively.

As a lessee, we have elected a short-term lease practical expedient on all classes of underlying assets, permitting us to not apply the recognition requirements of this standard to leases with terms of 12 months or less.

Our CPA identifies the "right of use" of a specific type and number of aircraft over a stated period-of-time. A portion of the compensation under our CPA is designed to reimburse the Company, as lessor, for certain aircraft ownership costs of these aircraft. We account for the non-lease component under ASC 606 and account for the lease component under ASC 842. We allocate the consideration in the contract between the lease and non-lease components based on their stated contract prices, which is based on a cost basis approach representing our estimate of the stand-alone selling prices.

As discussed in Note 1, we lease, at nominal rates, certain aircraft from United under our United CPA, which are excluded from operating lease assets and liabilities as they do not represent embedded leases under ASC 842. Other than nominal leases with United, one of our aircraft is leased from third parties, all of which are short-term leases. Our aircraft classified as operating leases results in rental payments being charged to expense over the term of the related leases. In the event that we or United decide to exit an activity involving leased aircraft, losses may be incurred. In the event that we exit an activity that results in exit losses, these losses are accrued as each aircraft is removed from operations for early termination penalties, lease settle up and other charges. Additionally, any remaining ROU assets and lease liabilities will be written off.