As the Northern Hemisphere gears up for what could be the busiest summer travel season in years, airlines and MRO providers are preparing for a sharp increase in flight operations, aircraft rotations – and, inevitably, unforeseen groundings.

Last year’s summer saw significant operational disruptions. Wizz Air, for example, grappled with up to 41 grounded aircraft at the peak of its engine troubles, forcing the airline to secure €300 million in compensation from Pratt & Whitney. To keep flights running, Wizz Air wet-leased eight aircraft at a cost of €39 million, yet profits still fell by more than 21 percent to €315 million over the period. This combination of grounded aircraft, hefty compensation payouts and wet-lease costs highlights the financial tightrope airlines walk when faced with engine-related AOG (aircraft on ground) events.

Similarly, airBaltic faced an average of six grounded aircraft in Q2 2024, leading to route suspensions and frequency reductions that affected over 67,000 passengers. These disruptions contributed to a net loss of €88.8 million in the first half of the year, driven by engine shortages and accelerated maintenance expenses.

Ryanair’s capacity was also constrained by a shortfall in aircraft deliveries and ongoing engine issues, prompting fare increases of approximately 10 percent this past summer — a sign of how supply pressures translate into direct costs for passengers.

As 2025 unfolds, airlines and MRO providers alike are doubling down on strategies to prevent a repeat of these costly disruptions. The industry’s focus is on improving engine reliability, expanding inventory availability and streamlining maintenance turnaround times.

Why engine failures peak in summer

Engine-related AOG events tend to spike during the summer months for several interrelated reasons. First, higher ambient temperatures — especially in regions like Southern Europe and the Middle East — cause greater thermal stress on engines. Hot-and-high conditions reduce engine performance and accelerate the degradation of turbine blades and seals, increasing the risk of in-service failures.

Second, summer is the peak of aircraft utilisation, with tighter schedules, heavier engine loads and fewer available maintenance windows. Aircraft are often pushed close to their cycle limits, making unscheduled engine removals more likely. In parallel, airlines may also choose to delay non-critical engine maintenance during high-demand months — deferring swaps or inspections to avoid taking aircraft out of service, which can amplify the chance of failures mid-season.

In such an environment, understanding the financial and operational impacts of engine AOG remains critical. Last summer’s data serves as a clear warning: engine reliability issues are not just technical problems but pivotal factors shaping the summer travel market in Europe and beyond.

Travellers should be aware that while improvements are underway, the ongoing effects of last year’s engine challenges may still impact flight schedules and fares this summer. Airlines that successfully manage their engine AOG risks will be best positioned to offer stable capacity and competitive pricing, while those still struggling with maintenance backlogs may see continued operational pressure.

Understanding the financial toll of engine-related AOG

When an aircraft is grounded due to engine problems, the direct costs alone can be staggering. Engine repairs or replacements can range from US$200,000 to over US$2 million depending on the engine type and the severity of the damage. Shipping and logistics costs for transporting engines or parts add another US$10,000 to US$100,000 or more.

Labour costs for AOG teams working overtime frequently add between US$5,000 and US$25,000 per incident. Beyond these direct expenses, the indirect costs weigh heavily on airlines as well. Loss of revenue from a grounded aircraft can reach US$10,000 to US$150,000 or more per day, depending on the aircraft size and route.

Passenger compensation under regulations such as EU261 or DOT can run up to US$700 or more per passenger, while rebooking and accommodation costs often add tens of thousands of dollars per flight. In some cases, repositioning the aircraft after repairs can cost anywhere from US$15,000 to upwards of US$75,000. On top of these are opportunity costs — the lost utilisation of the aircraft, especially for narrowbody planes on high-frequency routes, and the potential damage to an airline’s reputation or operational reliability metrics.

Altogether, the estimated total cost for an engine-related AOG event can vary widely: a single day on the ground might cost between US$50,000 and US$150,000, two to three days can push costs to between US$150,000 and US$600,000, and anything longer than three days can easily exceed US$600,000, potentially climbing over US$2 million.

For example, consider an AOG event involving a PW1100G engine on an A320neo. Repair and logistics alone can tally around US$300,000, with three days of downtime resulting in revenue loss of approximately US$250,000. Passenger disruption and associated costs might add another US$50,000, bringing the total AOG cost in this scenario to well over US$600,000. These figures naturally depend on multiple factors, including the aircraft model (such as an A320 versus a B777), the specific engine type (whether CFM56, GE90, PW1100G or others), and the terms of the airline’s maintenance contracts, whether they operate under power-by-the-hour (PBH) agreements or time and materials.

Unplanned removals and replacements can cost 30–50 percent more than planned maintenance due to the emergency logistics and equipment sourcing that become necessary. The longer the aircraft sits idle, the steeper the financial hit.

Summer 2025 is shaping up to be particularly high stakes. According to the latest data from IATA, global air passenger traffic is expected to grow 8.4 percent year-on-year. Load factors in Europe and North America are projected to exceed 85 percent during July and August, meaning that every grounded aircraft is more than just a lost opportunity: it also becomes a costly bottleneck in an otherwise full schedule and operations which should be as profitable as planned.

Airlines including Delta, Ryanair and Emirates have already announced expanded summer timetables, intensifying pressure on operations teams to prevent and recover quickly from disruptions. And with legacy aircraft powered by CFM56 and V2500 engines still playing a major role in global fleets, the likelihood of engine distress remains a reality that cannot be ignored.

Budgeting blind: the gap between forecasts and reality

Yet many operators and leasing companies still fail to budget properly for engine-related contingencies. Initial budget forecasts tend to only consider planned shop visits and scheduled stand leasing periods. What is often missed is the high likelihood of unexpected events that require urgent access to compatible engine stands.

In many cases, this gap between planned and actual needs can lead to emergency procurement, where costs surge and availability becomes uncertain. Last-minute sourcing can inflate leasing and transport expenses by as much as 60 percent, especially when relying on vendors who are not pre-vetted or based near the operations hub. The outcome is often a significant overspend compared to the original maintenance budget.

This is why it is essential to include EngineStands.com on your RFQ (request for quotation) list. When time is of the essence, every hour counts. EngineStands.com operates with speed and flexibility, offering rapid responses to urgent requests, all thanks to a global warehouse network spanning Dubai, Vilnius and Amsterdam.

Our wide inventory of engine stands includes key models such as the CFM56-3, CFM56-5A/B, CFM56-7B, V2500, LEAP-1A, LEAP-1B, PW1100G, GEnx-1B and many others – each maintained to the highest standards and ready for dispatch. Having us on your RFQ list means your team can immediately request pricing and availability without administrative delays and receive a same-day response, ensuring you stay ahead of the AOG curve.

The importance of being an approved supplier before any trouble starts

We have seen it too many times: a customer urgently needs an engine stand, but the compliance and KYC procedures are still pending. Internal delays in supplier onboarding often extend AOG by several avoidable days.

Getting EngineStands.com onto your Approved Supplier List (ASL) in advance is a low-effort, high-reward move. We work with airlines, MROs and lessors worldwide and meet the industry’s standard compliance requirements.

Time lost to compliance paperwork and contract negotiations during an emergency is time your aircraft stays on the ground. Many operators experience delays of two to five days solely because the chosen vendor is not pre-approved – days that could have been avoided with a simple administrative step taken in advance. Being an approved supplier means we can move faster, issue documentation without red tape and start logistics arrangements the same day a request comes in.

Preparation is profitability. As this summer shapes up to be both a commercial opportunity and an operational challenge, the smartest players will be those who plan for contingencies before they occur. Engine-related AOG will happen, as it is not a matter of if, but when. The only question is whether you will be ready to respond swiftly, cost-effectively and with minimal disruption to your schedule.

AOG prevention starts with preparation

EngineStands.com is ready to support your fleet, whether you are operating across Europe, the Middle East, Asia or the Americas. Contact our team today to check availability, begin onboarding, or reserve engine stands in anticipation of high-risk periods. The cost of not planning ahead could be measured in hundreds of thousands per incident. Let us make sure your aircraft stay in the air, where they belong.

In aviation, the difference between a minor delay and a major disruption often comes down to how well you are prepared. While AOG events can never be fully eliminated, their cost and duration can be significantly reduced.

At EngineStands.com, we believe that preparation is profitability. This summer, do not let a missing engine stand be the reason your aircraft stays grounded longer than it should. Let us help you turn unplanned into planned, and reactive into proactive.