The Boeing 737 MAX 10 has suffered another setback after the United States Federal Aviation Administration confirmed that certification will be delayed while a newly disclosed software issue is examined.

Approval had been widely expected during October 2026, potentially allowing Boeing to begin delivering the aircraft before the end of the year. That timeline is now uncertain.

The MAX 10 is the largest aircraft within Boeing’s latest 737 family and is designed to compete with the Airbus A321neo. Its additional capacity makes it particularly important to airlines attempting to carry more passengers without adding extra flights.

Among its largest customers is Ryanair, which expects the aircraft to support a substantial expansion across Europe. TUI also plans to use the MAX 10 as part of the continuing renewal of its European airline fleet.

So, what has caused the latest delay and should UK passengers be concerned?

The issue affects the automated flight guidance available to pilots during a specific type of missed approach or go-around.

A go-around occurs when the pilots discontinue an approach to the runway, apply power and climb away before preparing for another landing attempt. It is a standard and carefully practised procedure that can be triggered by weather, runway conditions, traffic or an unstable approach.

Under the scenario being investigated, the software may prevent pilots from immediately accessing a particular level of automated flight guidance. Pilots would retain control of the aircraft, but the situation could increase their workload during an already busy phase of flight.

The FAA has said it will delay certification of the MAX 10 until it is satisfied that the matter has been resolved. A Corrective Action Review Board is expected to examine the problem and determine the appropriate response.

Boeing has informed affected operators and is developing a permanent software update.

At this stage, regulators have not said that the issue makes the 737 MAX unsafe to fly.

United States Transportation Secretary Sean Duffy said there was no current reason to ground the existing fleet and compared the expected solution with a routine software update.

The FAA has nevertheless decided that the MAX 10 should not be approved until the concern has been fully assessed.

That cautious approach is understandable. Boeing and its regulators remain under intense scrutiny following the two fatal MAX 8 accidents in 2018 and 2019, which involved a different flight-control system.

The latest issue has not resulted in pilots losing control of an aircraft. Airlines operating the software have also reported no known in-service events associated with it.

However, the history of the programme means that neither Boeing nor the FAA can afford to dismiss a software concern without completing the necessary investigation.

The MAX 10 is the highest-capacity version of Boeing’s current single-aisle aircraft.

Its size allows airlines to carry more passengers than the MAX 8 while retaining commonality with the rest of the 737 family. Pilots, engineers and cabin crew can operate closely related aircraft without the airline introducing an entirely separate fleet type.

That combination of capacity and commonality is particularly attractive at congested airports where airlines cannot simply add more flights.

The aircraft is also central to Boeing’s attempt to compete with the Airbus A321neo, which has built a formidable order book among airlines seeking larger and more capable narrow-body aircraft.

More than 1,500 MAX 10s have reportedly been ordered, making certification crucial not only for Boeing but also for the growth plans of airlines around the world.

Ryanair placed a firm order for 150 Boeing 737 MAX 10 aircraft in 2023, with options for another 150. Deliveries are scheduled to take place between 2027 and 2033.

The airline originally expected its first aircraft during early 2027 and is currently planning to receive an initial batch of 15 before the summer season.

Following the latest setback, Ryanair Group chief executive Michael O’Leary said he hoped the delay would be short and maintained that the airline could still receive those first 15 aircraft during spring 2027.

Ryanair intends to configure the MAX 10 with 228 seats. That represents a considerable increase over the 189 seats found aboard its older Boeing 737-800s and the 197 carried by its 737 MAX 8-200 aircraft.

Those additional seats are central to Ryanair’s plans to grow towards 300 million annual passengers by 2034. They should allow the airline to increase capacity on popular routes without requiring a corresponding increase in aircraft movements.

The MAX 10 is also expected to replace some older aircraft as leases expire and the airline gradually reshapes its fleet.

An immediate wave of cancellations is unlikely.

Ryanair has not yet built its current schedule around a large operational fleet of MAX 10s. The aircraft has never entered commercial service, meaning the airline continues to operate using its existing Boeing 737-800 and MAX 8-200 fleet.

The greater risk emerges if certification and deliveries slip far into 2027.

Ryanair could then have fewer aircraft than expected for planned growth. It may respond by keeping older Boeing 737-800s for longer, reducing the number of new routes it launches or limiting frequency increases in selected markets.

The airline could also move aircraft between bases to protect its most commercially important schedules.

Ryanair has considerable experience dealing with delayed Boeing deliveries and has previously adjusted growth targets when aircraft were unavailable. That does not mean passengers will see no effect, but any changes are more likely to involve slower expansion than the sudden disappearance of existing flights.

The MAX 10 is intended to lower Ryanair’s cost per passenger by spreading the expense of each flight across more seats.

If deliveries are delayed, the airline may need to operate smaller aircraft or retain older jets that are less efficient. That would place some pressure on operating costs and limit the amount of new capacity entering the market.

Less capacity can contribute to higher fares, particularly during busy travel periods. However, aircraft delivery delays are only one of many factors influencing ticket prices.

Fuel costs, airport charges, taxation, competition and demand will remain far more visible drivers of what passengers ultimately pay.

It would therefore be premature to claim that the MAX 10 setback will directly increase Ryanair fares. A prolonged delay could nevertheless remove some of the capacity growth that normally helps keep prices competitive.

TUI Group is also waiting for the MAX 10 as part of a wider order covering 96 Boeing 737 MAX 8 and MAX 10 aircraft.

The group had received 55 of the smaller MAX 8 variant by early 2026, while its first MAX 10s are expected to be deployed initially from Amsterdam.

TUI operates several airlines across Europe, including TUI Airways in the UK, TUI fly Netherlands, TUI fly Belgium, TUI fly Germany and TUI fly Nordic. Aircraft can therefore play a role within the wider group even when they are not directly based in Britain.

For TUI, the larger MAX 10 is particularly suitable for heavily booked package-holiday routes. It offers additional capacity without requiring the airline to introduce another aircraft family.

If deliveries are postponed, TUI may need to retain older Boeing 737s, adjust how aircraft are allocated between its European airlines or lease additional capacity during peak periods.

Those responses can be expensive, but they do not automatically mean that holidays will be cancelled.

Package operators plan their summer flying programmes far in advance and can use a combination of their own aircraft, leased capacity and partner airlines to protect their schedules.

Ryanair’s MAX 10s are expected to be distributed across its European network, so UK airports are highly likely to see the aircraft once deliveries gather pace.

It will be particularly useful on busy routes where airport slots are limited or demand regularly fills the smaller MAX 8-200.

For TUI customers, the picture is less certain. The group’s initial MAX 10 deployment is expected to concentrate on Amsterdam, although fleet plans can change and aircraft may eventually be allocated elsewhere within the business.

Passengers booking a flight or package holiday should also remember that airlines can change aircraft types for operational reasons. Even when a MAX 10 is displayed during booking, another aircraft could ultimately operate the flight.

There is currently no confirmed revised certification date.

The answer will depend on how quickly Boeing and its suppliers can produce a satisfactory software update, how extensive the FAA’s review becomes and whether additional testing is required.

The problem could be resolved relatively quickly if regulators determine that it is limited in scope. A more extensive finding could require months of redesign, testing and approval work.

Certification by the FAA would also need to be followed by approval from other regulators, including the European Union Aviation Safety Agency, before European airlines can introduce the aircraft.

Even after approval, Boeing must prepare stored and newly manufactured aircraft for delivery, while airlines need to complete crew training and operational preparations.

The first passenger flight will therefore not necessarily follow immediately after certification.

The latest MAX 10 setback is significant for Boeing and frustrating for airlines, but it should not cause immediate alarm among UK passengers.

The software issue has not resulted in a loss of pilot control, and regulators have said there is currently no reason to ground the existing MAX fleet. Pausing certification until the investigation is complete is the correct response.

Ryanair has the greatest UK exposure because its order for up to 300 aircraft underpins ambitious long-term growth. If the delay remains short, the airline may still receive its first 15 MAX 10s in time for summer 2027. If it extends for several months, some planned capacity growth may need to be reconsidered.

TUI has more flexibility across its European airline group, although further delays could increase leasing costs and slow the retirement of older aircraft.

For passengers, the most likely consequence is not mass cancellation but slower fleet renewal and fewer additional seats entering the market. The MAX 10 remains an important aircraft for both airlines, but after repeated delays, neither should build its immediate schedule around a delivery date that Boeing has yet to prove it can meet.