Aircraft engines: who gets paid when planes cannot fly?

A grounded aircraft does not stop costing money. It stops earning the revenue that was meant to cover some of those costs. When an engine is unavailable, leasing a replacement may get the aircraft flying again. What the airline is buying is not simply a piece of machinery. It is access to flying days it would otherwise lose.

That makes engine shortages potentially valuable to businesses able to supply a replacement, a repair slot or an essential component. But it does not identify their profits. A lessor can collect more rent because it owns more equipment. A repair business can become busier without becoming more profitable. A manufacturer whose product needs unexpected work may have to compensate customers.

To understand who benefits, follow the payments rather than the parked aircraft. Public documents available on 6 September 2026 describe a market for availability, not a single industry-wide windfall. They also show that different engine programmes are no longer moving in the same direction.

The $2.6 billion figure is a cost estimate

An IATA–Oliver Wyman study published in October 2025 put airlines’ additional engine-leasing costs for 2025 at $2.6 billion. That is neither total lessor revenue nor lessor profit. The detailed calculation associates that amount with a 90-day shop turnaround scenario, compared with a 60-day baseline. It is a modelled cost and does not mean that every engine actually spent 90 days in a shop. 1

The report’s summary estimates $11.3 billion in additional costs across several aviation supply-chain disruptions, including fuel, maintenance, replacement engines and inventory. Calling the whole amount an engine-failure bill would misstate its scope. Delayed new-aircraft deliveries, which keep older aircraft operating longer, also enter the calculation. IATA repeated the estimates in December 2025. 1 2

Source: IATA / Oliver Wyman, p. 53 summary. Estimates, not supplier profits; broader scope than engines alone. Page 56 gives $1.3bn for inventory against $1.4bn in the summary: the unresolved discrepancy is disclosed here.

Data and notes

Category	USD bn
Deferred fuel savings	4.2
Maintenance	3.1
Engine leasing	2.6
Inventory carrying costs	1.4

IATA represents airlines. Its commissioned analysis usefully describes how costs arise, but it is not a disinterested industry audit. These are estimates for 2025; their continued use in industry discussions during 2026 does not turn them into a fresh measurement of 2026 costs. 2 11

Nor does an airline’s extra spending flow unchanged to a supplier’s shareholders. The supplier must acquire or finance the engine, maintain it, fund periods without a lessee and bear technical and commercial risks. The distribution of profit has to be investigated separately from the size of the bill.

The queue begins before the workshop

MRO means maintenance, repair and overhaul. An engine’s time away from service includes more than hands-on work. Shop access, transport, parts availability, inspections and the return to operation all matter. The June 2026 IATA–Emerton study examines those constraints in the new-generation single-aisle engine market, including CFM’s LEAP and Pratt & Whitney’s geared turbofan, or GTF. 3

Different problems need to be kept separate. A manufacturing defect requiring early inspections is not the same as disappointing durability in difficult operating conditions, a delayed component or a shortage of shop capacity. A 2024 US airworthiness directive illustrates the first category: anomalies associated with powder-metal material in certain Pratt & Whitney engines led to mandatory inspections and accelerated replacement of critical parts. That work serves a safety requirement, not an optional commercial preference. 5

The June report identifies a peak of 648 GTF-powered aircraft in prolonged storage in March 2025, roughly 28% of the 2,344 aircraft in its population. The definition includes both the powder-metal issue and other technical reasons. It is not a September 2026 grounding count or a count of engines removed solely for that defect. Two engines on an aircraft do not imply that both were removed simultaneously. 3 4

A hypothetical example captures the financial effect of a longer queue. Suppose a stable operation sends ten engines into maintenance each month. If each stays out for three months on average, roughly thirty will be unavailable at a time. A six-month stay doubles that stock to sixty, even though the monthly arrival rate has not changed. Replacement-engine demand can therefore remain elevated without a further increase in new removals.

The reverse matters for investors. Shorter turnaround times can release spare engines before every underlying technical problem has been eliminated. Scarcity depends on how quickly equipment comes back as well as how much new work enters the queue.

The airline is buying productive days

An airline’s practical question is not whether a lease rate sounds expensive. It is whether the replacement costs less than the flying it restores. In a simplified comparison, the relevant benchmark is the flights’ contribution: revenue less the costs that would be avoided if the aircraft remained parked.

Gross ticket revenue is the wrong measure. Restored flights consume fuel and other resources. Subtracting the same maintenance charge twice would create the opposite error. Aircraft rent and some staffing costs may continue under either choice. They matter greatly to the airline’s financial health, but costs that are genuinely identical in both options do not decide between them.

The acceptable engine rent then depends on the remaining outage, when the spare becomes available, installation and transport costs, and any compensation the airline retains or loses by returning the aircraft to service. An expensive spare may be attractive during a long, commercially valuable gap. The same engine at the same price may be useless if it arrives after the original engine returns.

There is a physical condition before any of that arithmetic becomes relevant: a compatible, serviceable replacement must actually exist. An economic comparison cannot establish technical suitability or authorise a maintenance shortcut.

The accompanying calculator compares parking with leasing for one aircraft missing one engine. Every input is hypothetical and editable. It does not claim to quote the engine market. A refundable security deposit is shown separately from economic cost: the deposit ties up cash, while its financing cost is an expense in the model.

Under the central example, a 120-day outage, a spare available after ten days and $12,000 of daily flight contribution produce a leasing advantage of approximately $499,000, with the other assumptions shown. That is an arithmetic result, not a forecast. Shortening the outage can reverse the decision because fewer restored flying days are available to recover the fixed logistics and installation bill.

l0g calculation, not observed market rates. Fixed inputs: 10-day spare delay; $12,000/day contribution; $4,000/day rent; $1,000/day usage; $100,000 fixed costs; $1,500/day grounding compensation; $250,000 refundable deposit funded at 8% annually. Common costs excluded. The deposit itself is not an expense.

Data and notes

Days	Grounded (USD)	Lease (USD)	Lease advantage (USD)
15	157,500	230,274	-72,774
30	315,000	306,096	8,904
60	630,000	457,740	172,260
120	1,260,000	761,027	498,973

A lessor’s accounts mix price, volume and utilisation

Willis Lease Finance is a useful test case. Its second-quarter 2026 lease revenue was $77.1 million, up from $72.3 million a year earlier. The company attributes the 6.7% increase to a larger average portfolio. That disclosure does not establish that daily engine rates increased. Its rental business also includes aircraft and other equipment. 8

Source: Willis Lease Form 10-Q, filed 4 August 2026. Four selected lines, not the total. Also includes aircraft and other equipment. Disposal gains are not gross sale proceeds; maintenance-reserve revenue is not a measure of quarterly cash collections.

Data and notes

Line	2025	2026
Lease rent revenue	72.268	77.137
Maintenance reserve revenue	50.743	46.456
Spare parts and equipment sales	30.354	21.180
Gain on sale of leased equipment	27.582	32.038

To identify pricing, an analyst would need comparable equipment, engine condition, contract duration, leased quantities and utilisation. Aggregate revenue does not supply those controls. A hotel business faces a similar analytical problem: higher receipts may reflect more expensive rooms, better occupancy or an additional property.

Maintenance reserves require another distinction. Depending on the contract, usage-related payments help fund later work; cash collection and revenue recognition need not occur together. Willis Lease’s published maintenance-reserve revenue includes non-refundable amounts as well as end-of-lease items. It cannot simply be read as the quarter’s workshop invoice. 8

Asset disposals introduce a third category. Sale proceeds, the carrying amount removed from the balance sheet and the resulting accounting gain are not three amounts to add together. The gain is the difference recognised in earnings, before the business’s other costs and taxes. That is why the chart explicitly labels disposal gains rather than treating them as gross equipment sales.

Even a higher market valuation does not immediately generate cash for an engine owner. Unless the equipment is sold, refinanced or leased on better terms, that value may remain an opportunity rather than a realised return. It can also fall. The relevant investment question concerns net income over the asset’s economic life, not simply its apparent value during a shortage.

For a manufacturer, extra shop visits can be a liability

The supplier responsible for a defect may face a cost rather than a windfall. RTX, Pratt & Whitney’s parent, recorded a $2.9 billion net pre-tax operating charge in the third quarter of 2023 for the powder-metal matter. This is the recognised charge reported in its results, not the initial estimate announced before the accounting was finalised. 7

Its report for the period ended 30 June 2026 still estimates approximately $700 million of full-year 2026 cash impact, including customer credits and the timing of partner recovery. That is an annual cash-flow estimate. It is neither a new charge equivalent to the 2023 amount nor cash already paid out during the first half. 6

Contract design changes incentives, too. Some maintenance arrangements charge by engine flight hour and transfer part of the technical risk to the provider. IAE’s FleetHour offering for the V2500 is an explicit example. Other things being equal, keeping the engine on wing can be more attractive under such an arrangement than sending it back to the shop repeatedly. Minimum billing, guarantees and exclusions still have to be checked in the actual agreement. 12

Elsewhere, keeping older aircraft in service can support an established aftermarket. Safran reported a 27.9% increase in US-dollar civil-engine spare-parts sales in the first half of 2026, helped notably by CFM56 demand and favourable mix. This is part of its adjusted operating reporting. It does not show that spare-part prices rose 27.9%, or that the increase was caused solely by a competitor’s GTF difficulties. 10

Several mechanisms can operate simultaneously. An older engine’s parts business can perform strongly while a newer programme incurs warranty costs. Combining one company’s growth figures with another programme’s groundings would not demonstrate a shared strategy of profiting from failure.

Spare engines are attracting fund capital

On 5 January 2026, Willis Lease and Blackstone Credit & Insurance announced a partnership targeting more than $1 billion of deployment over two years into engines and selected aircraft. A deployment target is not capital already invested on the announcement date. 9

Willis Lease’s half-year filing subsequently shows implementation: the BXCI fund began operating in April 2026. During the half year, Willis Lease sold it fourteen engines for $216.2 million, recognising a $33.3 million gain. The fund is a related party, and Willis Lease also earns management remuneration. Sale proceeds, the disposal gain and management fees are different flows. 8

The economic structure is straightforward. A specialist selects and manages the equipment while investors provide some of the capital. Selling assets can free the specialist to acquire others without ending its role in their operation. The risk has not vanished; it has been allocated across different balance sheets and contracts.

The danger for an investor is to capitalise an unusually intense, temporary replacement need as though it were permanent. If shop delays shorten, more engines become available. An engine generation can lose appeal, an overhaul can cost more than expected, or an airline can fail to pay. Returns then depend on the purchase price, any borrowing, technical spending and eventual resale value, not just the visible rent.

Capital can expand the supply of spare equipment. It cannot instantly manufacture an approved component or create an effective repair slot. Paying a scarcity price for an asset does not ensure that it will remain scarce.

Competition depends on access as well as capacity

A workshop is valuable only if it can perform the work. Skills, tooling, technical documentation, parts and approvals must come together. Competition therefore concerns access to those inputs, not simply how many companies own workshop buildings. The IATA–Emerton study highlights access constraints in newer engine maintenance networks. That assessment should retain its attribution: it was commissioned by the airline side of the market. 3

There are specific commitments rather than just competing narratives. In January 2026, IATA and CFM renewed their agreement supporting more competitive maintenance practices through February 2033. It covers CFM engines. It does not demonstrate that every manufacturer follows the same rules or that physical bottlenecks have been removed. 11

The strongest objection to a purely rent-seeking interpretation is substantial. Developing, certifying and supporting engines requires resources, while spare parts and ready-to-use engines tie up capital. High prices can remunerate that capacity and encourage more of it. Limited alternatives can also strengthen a supplier’s negotiating position. Both explanations may apply at once.

Separating them would require comparable negotiated prices, margins after technical costs, operation-specific turnaround times and a practical ability for customers to switch providers. I found no consistent public series that isolates a global engine-shortage windfall. Inferring its size directly from airlines’ additional expenditure would exceed what the data show.

The shortage is fragmenting

Improvement belongs in the analysis. In results published on 6 August 2026, Wizz Air reported 27 aircraft grounded by GTF issues at 30 June 2026, compared with 41 at 30 June 2025. These are two snapshots of one airline, not a global average. The 2026 release covers April–June, the first quarter of its 2027 financial year, rather than the first calendar quarter of 2026. 13

On 3 September, Reuters also reported Azorra’s assessment that Pratt & Whitney engine difficulties were easing in the regional and smaller single-aisle markets it discussed. That is testimony from a lessor, not a comprehensive availability measure. Improvements in one engine family do not automatically establish the same progress elsewhere. 15

For the LEAP-1B, CFM announced certification of durability improvements in July 2026, with a full production cutover expected in early 2027. That industrial milestone does not mean that every in-service engine already has the changes, or that all promised performance gains have been observed across the operating fleet. 14

None of this establishes that the disruption is over. It does rule out extending a March 2025 peak mechanically into September 2026 and then indefinitely into the future. For the owner of a spare engine, better technical performance can be welcome industrial news while gradually reducing the scarcity value of its equipment.

So who gets paid?

An owner with the right serviceable engine at the right time can sell valuable availability. A business with hard-to-replace repair capabilities may negotiate stronger terms. A manufacturer can benefit from demand for parts on one programme while bearing substantial warranty costs on another. Those mechanisms can coexist; they do not show that everyone benefits from every grounding.

Public accounts establish payment flows. They do not isolate a worldwide profit attributable to grounded aircraft. The contracts, the capital tied up and the duration of the shortage matter as much as the visible rental bill.

For the airline, the immediate decision is to buy productive flying days for less than their economic contribution. For the investor supplying the engine, the horizon is longer: what will that equipment earn when the workshop queue finally gets shorter?

Related: the residual value guarantee, the blind spot in credit financing AI infrastructure examines the same terminal-value risk for technology assets.

Sources and method

Information checked on 6 September 2026. Publication dates, measurement periods and forecasts are kept separate. Issuer filings and releases are primary but interested sources; IATA studies represent the airline side. The calculator’s scenarios are entirely hypothetical and are not calibrated to industry statistics.

[1] IATA / Oliver Wyman · 2025-10
Reviving the Commercial Aircraft Supply Chain
Airline-commissioned model, not audited accounts. The p. 53 summary uses 1.4bn for inventory, whereas p. 56 says 1.3bn; the unexplained discrepancy is retained, not silently corrected. Fuel cost uses a 2024 average price.

[2] IATA · 2025-12-09
Aerospace Supply Chain Bottlenecks Continue to Constrain Airlines
Restates the 2025 estimates from [1]. IATA represents airlines; this is not an independent new census.

[3] IATA / Emerton · 2026-06
Single Aisle Aircraft Engines MRO: Strategic Levers to Address Supply Chain Challenges
IATA-commissioned study. The 648 count is aircraft in prolonged storage in March 2025, not removed engines or a September 2026 count. Includes other technical reasons. Competition findings are attributed to the study.

[4] IATA · 2026-06-24
Urgent Action Needed to Ease Engine MRO Bottlenecks
Release date differs from observation dates. Repeating 2025 costs does not make them a 2026 measurement.

[5] US Department of Transportation / FAA · 2024
Airworthiness Directives; International Aero Engines, LLC Engines, Federal Register document 2024-06419
Historical example of mandatory safety measures for specified parts. Not presented as a complete list of directives applicable on 6 September 2026 or as coverage of every GTF variant.

[6] RTX / SEC EDGAR · 2026-07-23
RTX Form 10-Q, quarter ended June 30, 2026
Approximately $0.7bn forecast full-year 2026 cash impact, not realised H1 spending. Includes customer credits and partner recovery timing. Separate from the 2023 charge and remaining liability.

[7] RTX · 2024-01-23
RTX Reports 2023 Results and Announces 2024 Outlook
$2.9bn net pre-tax operating charge: recognised result, not the initial roughly $3bn estimate. Not added to the gross sales reduction as a second loss.

[8] Willis Lease Finance / SEC EDGAR · 2026-08-04
Willis Lease Finance Form 10-Q, quarter ended June 30, 2026
April–June quarter; USD thousands converted to millions. Rental growth attributed to average portfolio size, not a price index. Includes engines, aircraft and other equipment. Disposal gains differ from proceeds. BXCI fund is a related party.

[9] Blackstone / Willis Lease Finance · 2026-01-05
Willis Lease Finance Corporation Announces Aircraft Engine Leasing Partnership with Blackstone Credit & Insurance
Commercial announcement; deployment target rather than fully invested capital. Implementation cross-checked in [8], which records April 2026 commencement.

[10] Safran · 2026-07-28
Safran reports its first-half 2026 results
Civil engine spare-parts sales +27.9% in USD: revenue indicator, not unit prices. Adjusted reporting, not group IFRS revenue. Company cites CFM56, workscope mix and comparison base.

[11] IATA / CFM International · 2026-01-20
IATA and CFM International Renew Pro-Competitive Agreement on Engine Maintenance
Announced CFM commitment; it does not establish identical competitor practices or the removal of physical shortages. No finding of a competition-law breach is asserted.

[12] Pratt & Whitney / IAE · date not displayed
Fleet Hour Agreements
Supplier description: a V2500 example of risk transfer, not the terms of all GTF contracts or a guarantee of compensation for an airline’s lost profit.

[13] Wizz Air / RNS, republished by Investegate · 2026-08-06 and 2025-07-24
F27 Q1 results and F26 Q1 results
Primary RNS releases republished by a distributor; its automated summaries are not used. Two snapshots at 30 June. No total-fleet ratio is calculated because fleet counts elsewhere in the 2026 release conflict. Fiscal and calendar quarters remain distinct.

[14] GE Aerospace / CFM International · 2026-07-18
CFM secures certification for LEAP-1B durability upgrades
Attributed manufacturer announcement. It does not establish a complete in-service retrofit or fleet-wide realised performance. Early-2027 production timing is forward-looking.

[15] Reuters / Gabriel Araujo · 2026-09-03T12:37:00Z
Aircraft lessor Azorra sees engine issues improving, strong demand for regional jets
Lessor testimony in a regional and small-single-aisle context. Useful counterevidence, not a comprehensive grounding count or proof of resolution across engine families.