The Grass Isn't Always Greener: Why Airlines Are Grounding Their "Fuel-Saving" Jet Engines

You buy a new car that promises 50 miles per gallon. You're thrilled. That's the dream. But then you discover the engine needs to be rebuilt every 15,000 miles instead of every 100,000. And the repair shop is always booked solid. And the engine parts are backordered for months.

Suddenly, that fuel savings doesn't feel like such a bargain anymore.

That's exactly what's happening across the airline industry right now, on a massive, multi-billion-dollar scale. The newest generation of jet engines, the ones that were supposed to slash fuel bills and carbon emissions, are spending more time in repair shops than they are on wings. And airline CEOs are furious.

At the industry's largest annual gathering in Rio de Janeiro this month, the message to engine makers was blunt and unmistakable: You promised us efficiency. You delivered headaches.

"We have become the test beds of the technology," LATAM Airlines Group CEO Roberto Alvo told the Aviation Festival Americas in Miami. "That's simply not right."

Here's the full story of why the grass isn't always greener with new engines, and what it means for the future of flying.

The Seductive Promise of Next-Gen Engines

Let's rewind a decade. Pratt & Whitney, CFM International (a joint venture between GE and Safran), and Rolls-Royce were all racing to develop the next big thing in aviation propulsion. The goal? Dramatically better fuel efficiency, lower emissions, and quieter operations. The business case was ironclad: fuel is an airline's single biggest expense after labor, often accounting for 20–30% of operating costs. A 15–20% reduction in fuel burn would be a game-changer.

And the technology delivered, on paper.

Pratt & Whitney's Geared Turbofan (GTF) engine, which powers the Airbus A220, A320neo family, and Embraer E2 jets, promised up to 20% better fuel efficiency and a 75% smaller noise footprint compared to prior-generation engines. CFM's LEAP engine, which competes directly with the GTF on narrowbody jets, offered similar efficiency gains. Rolls-Royce's Trent family and GE's GE9X were designed to push widebody aircraft into a new era of fuel economy.

Airlines ordered thousands of these engines. They couldn't wait to start saving money and bragging about their green credentials.

But then the planes started breaking.

The Engine-by-Engine Breakdown

Not all new engines have failed equally. Some have been disasters. Others have been merely disappointing. But across the board, a troubling pattern has emerged: engines are leaving wings far sooner than anyone expected.

Pratt & Whitney GTF: The Crisis at the Center

The GTF has been the epicenter of this storm. What began as a promising new architecture, a gearbox that allows the fan and compressor to spin at different optimal speeds, has turned into a multi-billion-dollar liability.

In 2023, Pratt & Whitney discovered that contaminated powdered metal had been used in the manufacture of critical components, leading to microscopic cracks that could cause corrosion and part failure. The recall affected not hundreds but thousands of engines. By late 2025, some 770 GTF-powered jets were sitting in storage, most grounded due to engine issues. Wizz Air, one of the hardest-hit operators, has had as many as 41 aircraft grounded at a single time due to GTF-related inspections.

The pain isn't limited to budget carriers. Air Austral, a small Réunion Island-based airline, announced it would retire its entire fleet of four-year-old Airbus A220s — abandoning the aircraft type entirely, because the GTF engines made operations untenable. The airline's chairman said the situation was so dire that two of three A220s were typically grounded, leaving the carrier with effectively 1.75 usable aircraft out of three.

Swiss International Air Lines, which operates 30 A220s, expects engine-related issues to persist "throughout the decade." Its A220 fleet logged only 4,600 flight hours in September 2025, down from over 6,100 in September 2019, a 25% drop in utilization.

Pratt & Whitney's parent company, RTX, has taken a $3 billion charge related to the crisis, with total repair costs and airline compensation estimated between $3 billion and $7 billion. Italian carrier ITA Airways is actively considering a lawsuit, claiming damages of around €150 million and noting that "almost 20%" of its fleet has been grounded.

CFM LEAP: Better, But Not Bulletproof

If the GTF is the crisis, the LEAP is the quieter disappointment. CFM International's answer to the GTF has generally performed better, with fewer systemic grounding events and a faster path to reliability improvements.

By late 2025, LEAP engines were achieving longer real-world Time On Wing (TOW) and higher fleet utilization than current GTFs, with LEAP-powered narrowbodies showing around 12% ground days compared to the upper 30s for GTF aircraft.

But "better" doesn't mean "good enough." LEAP engines have faced their own durability issues, particularly with high-pressure turbine (HPT) blades in hot, dusty environments. WestJet CEO Alexis von Hoensbroech summed up the frustration of many airline leaders: "The three of us can probably name the top three problems that a LEAP engine will have, or a Pratt & Whitney GTF will have. Right now, it's easy to predict."

CFM has rolled out HPT durability kits certified in 2024–2025 and claims TOW is now "in line with CFM56", the legendary previous-generation engine that set the durability benchmark. Still, the gap remains, and the industry is watching closely.

Rolls-Royce: Trent Troubles Across the Atlantic

Even Rolls-Royce, the British icon of high-end jet engines, hasn't escaped unscathed. Its Trent 1000 engines, which power Boeing 787 Dreamliners, have suffered from premature wear and tear of turbine blades, leading to cracks and erosion that could result in in-flight shutdowns.

In 2017, Rolls-Royce confirmed durability issues affecting up to 500 engines globally. By 2018, the FAA issued an airworthiness directive banning extended operations for 787s equipped with affected Trent 1000s. The Trent 7000, which powers the Airbus A330neo, has faced similar problems.

More recently, in late May 2026, a Virgin Atlantic A330neo powered by Rolls-Royce Trent 7000 engines was forced to divert to Shannon, Ireland, after an engine issue over the Atlantic Ocean. The flight, carrying 241 passengers, was about three hours out when the crew had to reduce power on the affected engine and turn back. No one was hurt, but the incident highlighted the ongoing vulnerability of these new-generation engines.

Rolls-Royce says it is "on track" to deliver a 30% TOW improvement for the Trent 1000 and Trent 7000 by the end of 2025, with a second phase offering another 30% gain. But for airlines already burned, promises are wearing thin.

GE9X: Trouble Before Takeoff

Even GE's giant GE9X, the world's largest commercial jet engine, designed for Boeing's long-delayed 777X, has hit durability snags before even entering service. In early 2026, Boeing identified a "potential durability issue" with the GE9X involving a mid-seal crack. The problem required analysis and potential redesign, though GE insists it won't delay 2027 deliveries.

For a program already years behind schedule, it's yet another setback. And for airlines eyeing the 777X as their next long-haul flagship, it's another reason to hesitate.

The Fuel Savings Paradox

Here's the cruel irony at the heart of this entire story: The very thing that makes these engines so efficient, extreme heat, is also what's killing them.

Newer engines burn hotter than their predecessors. Higher combustion temperatures mean more complete fuel burn and better efficiency. But heat is also the enemy of metal. Turbine blades that operate at temperatures high enough to melt rock are inevitably going to wear out faster.

"The newer engines run hotter and offer higher fuel efficiency. But the heat and pressure increases lead to early durability challenges," explains industry analysis firm AirInsight.

Azul CEO John Rodgerson put it even more bluntly: engines are "just not lasting as long."

And the repair bills? They're astronomical. WestJet's von Hoensbroech noted that in some cases, airlines are forced to replace components costing "$1.5 million" instead of performing repairs that might cost "$100,000."

So the math that once looked so attractive, fuel savings minus maintenance costs, is now upside down for many operators. Chromalloy CEO Chris Celtruda warned that the fuel burn savings from next-generation engines "may never offset the decreased reliability of shorter service intervals."

Airline Pain in the Real World

Let's get specific about what this actually means for airlines trying to run a business.

• Grounding numbers: At its peak, more than 700 GTF-powered A320neo aircraft were grounded (AOG, Aircraft on Ground). By early 2026, that number had dropped by about 20%, but Pratt & Whitney's president warned the situation "will continue on for a couple years."
• Financial toll: Total airline compensation from Pratt & Whitney is estimated at $3–7 billion, but many carriers say it's not enough.
• Market shift: LEAP now powers approximately 75% of A320neo orders, as airlines have favored the more reliable (but still imperfect) option.
• Legal action: ITA Airways is considering a lawsuit against RTX, while other carriers have quietly settled for confidential amounts.
• Fleet decisions: Air Austral is scrapping its A220s. EgyptAir sold its entire A220 fleet. AirBaltic took heavy losses. The list keeps growing.

Willie Walsh, the outgoing director general of the International Air Transport Association (IATA), told the Rio conference he is "deeply disappointed customers have not dented manufacturer finances," suggesting airlines are bearing too much of the burden while engine makers continue to profit.

What's Being Done About It

To be fair, the engine manufacturers aren't sitting idle. They're spending billions on fixes, upgrades, and expanded repair capacity.

Pratt & Whitney has introduced two major upgrade paths:

• Hot Section Plus (HS+) : A retrofit for existing GTFs that uses about 35 new parts and delivers 90–95% of the durability benefits of the new Advantage engine. Nearly doubles Time On Wing. Installations began in 2026.
• GTF Advantage: A new-build standard with completely redesigned hot section components. Certified in 2025, entering service in 2026. Doubles TOW in harsh environments to about two years.

Pratt has also ramped up maintenance capacity, with MRO output up 23% year-over-year, and the number of AOGs declined 15% in early 2026.

CFM has rolled out HPT durability kits that have been installed on more than 50% of the LEAP fleet, with claims that TOW for low-thrust LEAP-1As in harsh environments has grown from 1.5 years to about four years, or roughly 8,000 cycles.

Rolls-Royce is pursuing an 80% TOW improvement across its modern Trent family by 2027, with more than half already delivered or secured.

GE is working on a fix for the GE9X mid-seal issue and insists it won't delay the 777-9's 2027 debut.

But these fixes will take time to propagate through global fleets. Wizz Air, for example, doesn't expect to have its entire fleet unparked until the end of 2027.

What This Means for Passengers

You might be reading this as a traveler, not an airline executive. So what does all of this mean for you?

Higher fares. When airlines have to ground planes, or spend millions on unplanned maintenance, those costs get passed along. Industry net profits are expected to fall from $45 billion in 2025 to $23 billion in 2026, and net margins from 4.2% to just 2%. To stay profitable, airlines have to charge more.

Fewer flights. Every grounded aircraft is a flight that can't operate. At airlines with significant GTF exposure, that means thinner schedules, especially on routes that rely on A320neos or A220s.

Potential reliability anxiety. When you hear about engine issues mid-flight, like the Virgin Atlantic diversion over the Atlantic, it's natural to feel a twinge of concern. The aviation system remains extraordinarily safe. But the headlines don't help passenger confidence.

The Grass Isn't Greener. Now What?

The aviation industry is learning a hard lesson: you can't have your fuel savings and eat them too, at least not without paying a steep price on the maintenance side.

For airlines, the decision going forward is agonizing. New engines still offer efficiency advantages, especially as fuel prices remain volatile and environmental pressures mount. But the operational chaos and financial bleeding are forcing carriers to think twice about future orders.

Some, like LATAM's Alvo, are calling for a pause, a moment to ask "how to do it better" before the next wave of technology arrives. Others, like WestJet's von Hoensbroech, are warning engine makers that their business model, profit from repairing your own unreliable products, risks long-term damage to customer relationships.

The manufacturers, for their part, are investing heavily in fixes and upgrades. The next-generation GTF Advantage and LEAP durability kits should make things better. But "should" is doing a lot of work there.

One thing is certain: the era of assuming that newer engines automatically mean lower costs is over. Airlines are waking up to the reality that the grass isn't always greener, sometimes it's just different grass, with different problems.

And for the rest of us watching from the passenger seat, it's a fascinating reminder that even the most sophisticated engineering can't always deliver on its promises without some painful trade-offs along the way.