Engine Shortage in Aviation: Why Maintenance Bottlenecks May Affect Summer Flights?

According to a fresh warning issued by IATA on June 24, a bottleneck has developed around the maintenance and repair of engines for the latest generation of narrow-body aircraft, which is no longer just a problem for the technical departments of airlines. The situation may affect capacity, schedule stability, the availability of spare aircraft, and indirectly, the summer travel planning of passengers.

For Hungarian travelers, this is important because a significant portion of departures from Budapest and Vienna fit into a European network where modern Airbus A320neo and Boeing 737 MAX family aircraft are playing an increasingly larger role. These aircraft are more fuel-efficient, quieter, and promise cheaper operation in the long run, but the associated engine maintenance capacity is currently not keeping pace with fleet growth everywhere. This does not mean that mass flight cancellations should be expected on every route, but it does mean that during the peak summer season, it is advisable to be more cautious with overly tight connections, separate bookings, and last-minute modifications.

What happened now?

The International Air Transport Association, IATA, published a new study on the maintenance, repair, and overhaul (MRO) market for the engines of the latest generation of narrow-body aircraft during the World Maintenance and Engineering Symposium in Madrid. The organization specifically highlighted the CFM LEAP and Pratt & Whitney Geared Turbofan, or GTF, engines, as these power the majority of the modern Airbus A320neo family and Boeing 737 MAX aircraft.

According to IATA, the problem is caused by several factors simultaneously: issues related to engine durability, a shortage of spare parts, limited availability of spare engines, and the fact that not all maintenance providers have flexible access to certain parts of the repair market. The organization states that these pressures are already disrupting airline operations, as more aircraft must remain grounded for longer periods while the number of engines sent to repair shops increases.

One of the most important figures from the study is that the number of aircraft grounded due to Pratt & Whitney GTF engines peaked at 648 aircraft in March 2025, representing half of the given GTF fleet. IATA also indicates that maintenance demand could grow steeply in the long term: the number of annual shop visits for LEAP engines could rise from the 600-800 range in 2025 to over 5,000 by 2040, while for GTF engines, the volume could grow from around 1,000 to over 2,000.

Why does this matter to passengers?

Aircraft engine maintenance may seem like an industry background issue at first, but passengers can definitely feel the consequences. If an airline has fewer usable aircraft, it must operate with a tighter spare fleet. This becomes particularly unpleasant when several disruptive factors occur simultaneously: bad weather, airspace restrictions, airport capacity shortages, a late-arriving previous flight, or staffing rotation issues.

Normally, a delay or technical replacement can often be handled with a spare aircraft. However, if spares are already tight, even a minor glitch can more easily disrupt the daily schedule. This does not automatically mean flight cancellations, but rather greater vulnerability: later departures, aircraft swaps, different configurations, and in rarer cases, consolidated flights or schedule thinning. From the passenger's perspective, the essence is that the existence of a scheduled flight is not always a guarantee that everything will turn out exactly as it did at the moment of booking by the end of the day.

The topic is especially important for the Hungarian market because both Budapest and Vienna are strongly connected to European low-cost and network aviation. Passengers departing from Budapest Liszt Ferenc Airport often travel via direct European flights or through major hubs. For many Hungarian passengers, Vienna Airport is an alternative departure point, especially for longer trips, a wider choice of flights, or better prices. If an airline's capacity is strained, real-time flight monitoring and a flexible itinerary become more important for both airports.

Not just one airline's problem

The current IATA alert is not about the problem of a single company. Modern engines are widespread, and the bottleneck can simultaneously affect manufacturers, leasing companies, maintenance companies, and airlines. According to IATA, while manufacturers are expanding capacity, capacity expansion alone is not enough if there are few approved repair solutions, spare parts are hard to obtain, or too few independent shops can enter the market.

For Hungarian readers, the example of Wizz Air makes the topic particularly tangible, as the airline is strongly tied to Central European markets. A recurring element in the company's recent financial communications has been the grounding of aircraft related to Pratt & Whitney GTF engines: in the 2026 financial year, an average of several dozen aircraft were out of service, while the number of grounded aircraft improved by the end of the year. This is an important nuance: the problem is not new, nor is it necessarily worsening for every airline, but IATA's current warning signals that the entire industry repair system must become more sustainable.

The situation is complex because modern aircraft are popular for a reason. They consume less fuel, promise lower emissions, and the business models of airlines are often built on these more efficient aircraft. However, if part of a new generation fleet is out of service for a longer period, airlines may be forced to continue using older aircraft, extend leases, rent supplementary capacity, or increase supply more cautiously. This may manifest in ticket prices, schedules, and service reserves.

What does this mean for summer travel planning?

The most important advice: there is no need to cancel flights in a panic, but it is worth leaving fewer margins for error in the itinerary. The greatest risk is usually not that a direct flight will certainly not depart, but that a too tightly organized travel chain collapses due to a delay. This is especially true if someone combines a low-cost flight, a long-haul flight, a train, a bus, a hotel check-in, or a ship departure in separate bookings.

Those departing from Budapest should check the Budapest Airport live flight information before departure, especially for morning connections and evening arrivals. For those flying from Vienna, the Vienna Airport current flight board is similarly useful. At major European transfers, the traffic situation at Frankfurt Airport, London Heathrow, or London Gatwick can also influence whether a delay becomes a real problem.

It is worth following at least a few practical rules. Do not plan a self-assembled transfer with a 60-90 minute buffer if the two flights are on separate tickets. Before a sea cruise, wedding, conference, or long-haul intercontinental departure, it is better to arrive in the departure city a day earlier. In the case of expensive or hard-to-modify accommodation, check under what conditions the booking can be changed. For travel insurance, check exactly what the coverage for delays, flight cancellations, missed connections, and extra accommodation costs extends to.

What is expected in the industry?

IATA names four main directions: better supply chain visibility, a more open aftermarket, more efficient use of digital data and artificial intelligence, and expanding professional capacity. These are not overnight solutions. An engine repair ecosystem consists of certifications, parts manufacturing, shop capacity, engineering knowledge, leasing agreements, and safety regulations. Therefore, the easing of the problem may also be gradual.

In the short term, airlines are expected to continue applying various tactics: keeping older aircraft in service, renting supplementary capacity, modifying schedules, or planning growth more cautiously. The passenger does not always see this background process, only that the departure time changes compared to an earlier booking, a different aircraft type appears, or there are fewer favorably priced seats on a popular route.

The good news is that the aviation safety system is not built on continuing to use faulty engines. If an engine needs inspection, repair, or overhaul, the aircraft cannot fly as if nothing happened. The inconvenience is therefore primarily a capacity and schedule issue, not a message that flying itself has become more dangerous.

What should the Hungarian traveler do now?

Those flying in the coming weeks should think through three things in advance. First: how critical is the arrival time? If very, then leave an extra day or choose an earlier flight. Second: is there a real alternative, such as another Budapest or Vienna departure, rail travel to a nearby airport, or a connection handled by the airline on a single ticket? Third: does the booking and insurance cover the case if the schedule changes?

IATA's fresh report is therefore not a single summer alarm, but a warning that one of the quiet constraints on aviation growth has become the maintenance background system. Those who understand this as passengers will not necessarily travel less, but will book more smartly: with more buffers, better information, and fewer risky independent transfers.

Sources and editorial note

The article is based on the IATA engine maintenance report of June 24, 2026, the supply chain priorities published on the same day, IATA's professional statements in Madrid, and Wizz Air investor and annual reporting data. The conclusions should be handled cautiously: the engine maintenance bottleneck does not mean automatic flight cancellations on every affected route, but it increases the importance of travelers checking the schedule, connections, and booking conditions before departure.