Faced with this situation, airlines must prepare for possible delays in the delivery of certain models, including the A350, next year, the same sources suggested. This is due to longer lead times for parts deliveries, two sources said. This prospect has forced the European manufacturer to mobilize additional resources to maintain the pace of deliveries.

Figures released on Wednesday show that Airbus needs to increase deliveries by 11% in the final quarter to reach its target of 770 aircraft for the year. Some analysts have revised their estimates downwards to 750 or 760 aircraft. "We note an overall low level of A350s in Airbus' inventory, which we believe could contribute to the risk of a slight deviation from Airbus' target of 770 deliveries for fiscal 2024," believes analyst Chloé Lemarié at Jefferies.

Boeing's main supplier, Spirit AeroSystems, which is in the process of acquiring its former subsidiary, is also being asked by Airbus to supply major components for its A350 twin-aisle and A220 single-aisle aircraft. In July, against a backdrop of industrial crisis exacerbated by the mid-air incident involving a Boeing aircraft, Airbus agreed to take over the two loss-making sites, while Boeing finalized the purchase of the remainder of Spirit.

Spirit denies

The American subcontractor asserted that its production was on schedule. "We are delivering Airbus products on schedule with our customers," said Spirit spokesman Joe Buccino. An industry source close to the matter said that the recent problems concerned the manufacture of composite clips for the spars, the components used to attach the supports. Buccino said this activity had "no impact on deliveries to Airbus' final production line".

Airbus employees have been dispatched to the Kinston plant to monitor performance, the sources added. Buccino said the presence of Airbus staff was part of a long-standing continuous improvement program, without pointing to any new urgent production issues.

Airbus acknowledged that Spirit, like other suppliers, was the subject of particular attention. "We have repeatedly highlighted the supply chain challenges we face, particularly in the aerostructures sector, and Spirit is one of them," said an Airbus spokesperson. The company is stepping up its presence with suppliers "where it is most needed", he added.

Special flights

The sources cited concerns about the production of fuselage sections at Spirit's Kinston, North Carolina plant. In addition, Airbus has stepped in to speed up the supply of wings for the smaller A220, airlifting parts from the supplier's factory in Belfast, Northern Ireland.

There have been reports of unusual movements of one of the world's largest cargo aircraft, an Antonov An-124, which was used to transport A220 wings by air rather than sea.

According to Quebec media TVA Nouvelles, the aircraft landed in Quebec City on September 14, attracting attention on its way to a factory on the outskirts of Montreal, where the Canadian-designed A220 is assembled. According to planefinder.net, the aircraft has made the journey from Belfast, where Spirit manufactures the A220's wings, to Montreal three times since mid-September.

A source from the A220 factory said that the expensive airlift had been implemented to support production. The exact number of flights was not immediately clear. Spirit confirmed several flights, citing a "substantial increase" in A220 production. An Airbus spokesman said the move was aimed at anticipating production needs.

Airbus CFO Thomas Toepfer had warned analysts in July that the company was facing supply difficulties, mainly for engines and landing gear. However, analysts are alarmed at the possibility of these problems spreading to other critical components in the supply chain.

"Our biggest concern is that Airbus' task is not limited to solving the problem of a single supplier, but of several," stressed Bernstein analysts.