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AFAICT they don't exist at all today. They are just renderings. So double clickbait. A more accurate title would be, "Airbus announces plans to develop foldable wing extensions, with non-foldable versions as the first step" or something like that.

https://www.airbus.com/en/newsroom/press-releases/2026-07-ai...

https://theaircurrent.com/aircraft-production/boeing-massive...

It begs for a video too!

My 2c:

The goal is longer, thinner wings than usual. Long and thin wings are far more efficient—think gliders and the U2. But beyond a certain width, those wings become incompatible with existing airports and other facilities for handling commercial aircraft. So the idea is to mount folding extensions that are extended for flight, but likely fold when being hangered or navigating taxiways.

Ground infrastructure.

E.g. for the 777X it fits in Category E. Without folding tips it would be in Category F. Less gates can accommodate Category F.

https://skybrary.aero/articles/icao-aerodrome-reference-code

> The Wing of Tomorrow programme is centred around creating longer, lighter, and more slender wings to maximise aerodynamic efficiency and reduce fuel burn. The wing extensions will be assembled at Airbus’ Wing Technology Development Centre in the UK and flight tested in Toulouse.

An airliner weighs a certain amount. In cruising flight, the lift on the aircraft is exactly equal to the weight (because it's neither climbing nor descending). Aerodynamic drag falls into 3 buckets: parasitic drag, wave drag, and lift-induced drag. Lift-induced drag is drag created by the wings producing lift.

Longer, thinner wings (higher aspect ratios) create less lift-induced drag for a given wing area, so ideally you want a super duper long and skinny wing, which will create less drag for a given amount of lift, and thus improve your fuel efficiency. Fuel is a massive portion of the total cost of operating an airliner, so there is a large financial incentive from the airlines to reduce fuel costs.

Unfortunately really long wings make airliners too wide to park at most airport gates, and in some cases too wide to taxi safely around obstacles, so they're experimenting with ways to make the wings fold and get a "best of both worlds" situation.

Operation from aircraft carriers, obviously. /s

20% efficiency means you can open single isle flights on 25% longer distances, which open a lot of routes that are not profitable with regular long haul planes.

I've flown on the A321LR a few times, and it's always crazy to think about that tiny plane cruising over the Atlantic without stops.

10-20% efficiency is enormous considering fuel is by far the dominant lifetime cost of operating an aircraft.

New fuels (SAF) and the technology to use them have been developed for less.

This is all to say nothing of the continuous work done over decades now to make aircraft more efficient; as these effects compound, intuition says that returns would start diminishing, so 10-20% is even more impressive.

The first paragraph of your comment is very informative. The rest, not so much. I highly suggest editing the rest out.

20% would be an absolutely massive accomplishment. Think about how many decades of incremental improvement have gotten us to the efficiencies we have today.

This is a massive improvement for airliners where margins are a few %. Tube and wing configuration is already highly optimized. This is a physical problem with a hard limit. Can you make a sphere "exponentially" rounder?

Military aircraft have done this for decades to deal with the confined space on aircraft carriers. It's not a new idea, nor any kind of new technology.

Yeah, Boeing has the 777X that features folding wingtips. It still going certification and is looking like it'll be out next year (originally 2020).

Yes this is on the 777x, which is in pre-production and flight testing, seeking approvals from the FAA

You're right, it's a proof of concept: "The extensions, each measuring several metres, will replicate a folding wing in the fully extended position during a flight. They will be fitted with comprehensive testing equipment to capture behaviour in flight and evaluate how the longer wingspan impacts aircraft handling."

Not just the shape, but also the mass placement and rigidity. I explain this in another comment, I don't want to cut and paste redundant info here but keep scrolling and you'll find it ))

Let's hope, it doesn't fall off...

Cool, but then you'd be forced to fly on a Boeing.

Is that the plane that is already 7 years late due to certification issues?

Neat! https://en.wikipedia.org/wiki/Boeing_777X#Wing

Foldable wings have been on aircraft carriers for a while as well.