At a Welsh airfield near Caernarfon, two turbines went up 98 feet from a runway edge, and the 3,543 foot strip has flown unlicensed for over a decade
Twice a day, a pilot radios the tower at a small Welsh airfield.
They ask permission to land on a runway that technically does not exist anymore.
The asphalt is still there.
One flier’s complaint, captured in contemporary reporting, put it bluntly: “we had years of using just one runway and the crosswind problems that caused.
So are the markings.
But the license that once made it official disappeared the day two turbines went up beside it.
What actually happened to the paperwork starts with how close those blades really sit to the centerline.
How two turbines outrank a runway’s own license
Aviation regulators work from fixed geometric slopes that fan out from a runway’s edges and ends, invisible cones of airspace that must stay clear of anything solid. A civil aviation authority does not ask whether a turbine is dangerous in the abstract, it checks whether the structure intrudes on that protected volume.
If it does, the runway’s certification is the thing that gives way, not the turbine. At Caernarfon, the two machines were built to stand 152 feet above sea level, positioned roughly halfway down the runway’s length and only about 98 feet from its edge.
That is well inside the margin regulators expect to stay empty, so the runway’s own safety case collapsed the moment the towers were finished. The airfield’s directors knew this going in.
A record of the original planning submission to the local council noted the operators “would therefore cause this runway to become unlicensed,” and that the airfield operator “seemingly see this as a positive.” They built the turbines anyway, and the license lapsed exactly as the paperwork predicted.
What the airfield looks like now, turbines and all
Caernarfon Airport sits on Wales’s northwest coast near Dinas Dinlle, a small general aviation field built on the old wartime runways of a former RAF station. It keeps two strips: one, numbered 07/25, remains fully licensed and handles the bulk of scheduled training and pleasure flights.
The other, 02/20, is the one with turbines standing in its strip. So the field did not shut, it simply shrank its official capacity by half.
Pilots who still want to use 02/20 can, but only on the airfield’s terms. The operator’s own guidance states plainly that “Runway 02/20 at Caernarfon is now permanently unlicensed due to the installation of two 152′ AMSL wind turbines approximately half way down the runway, 98 feet from the runway edge,” and that it “can be used on the understanding of the conditions of use & also with advance permission granted from the airport manager.”
A runway that any pilot could once simply join now requires advance permission first.
The paper trail, and how close it came to fourteen turbines
The case is unusually well documented because the airfield itself is the applicant, not a neighboring landowner, which is the detail that makes this curious rather than merely contentious. Planning records from the original 2010 application show the scheme almost went much further.
An early scoping document described a plan for 14 turbines of 250 kilowatts each, standing a total of 148 feet tall, with seven placed on either side of runway 02/20. After a winter bird survey, that number was cut down sharply.
Only two machines survived the revision, sited to one side of the strip to limit collision risk, the same pair still turning there today. Local pilots objected at the time, warning that losing the crosswind runway again would hit smaller aircraft hardest.
One flier’s complaint, captured in contemporary reporting, put it bluntly: “we had years of using just one runway and the crosswind problems that caused. Then 02/20 was brought back into action and now it’s being shut. I think the microlight guys have had it.” The turbines were approved regardless, a modest output apiece that nonetheless outweighed, procedurally, a public use runway over 3,500 feet long.
A tradeoff still playing out more than a decade later
What makes Caernarfon worth watching is how ordinary the arrangement has become. Air traffic guidance for the field now folds the turbines into standard operating notes, including a no helicopter rule within 985 feet of the towers, treated as routine as a taxiway closure.
Yet the wake turbulence question that complicates rotor blocked airspace elsewhere remains a live safety variable here too. Incident reports at other UK airfields have documented aircraft encountering turbine wake miles downwind, even if no comparable Caernarfon incident has been reported.
Even so, the airfield has kept flying, kept its museum and café open, and kept training pilots on its one remaining licensed strip. The arrangement has held since the turbines went up, longer than many disputed wind projects ever get to prove themselves one way or the other.
Other airports have gone further in the other direction, leaning fully into on site generation rather than losing a runway to it. A 330 kilovolt substation near Wellington, New South Wales shows how differently that tradeoff can be engineered when wind comes first.
Caernarfon took the opposite route almost by accident, trading half its runway capacity for two small machines it never fully replaced with anything bigger. Projects sited with more distance, like the careful turbine spacing seen around sensitive flight paths in Scotland, show that geometry decided early can avoid exactly this outcome.
At Caernarfon, the geometry was decided late, after the turbines already stood where the slope used to be clear. The airfield’s own pilot notice still spells out the condition today, and more than a decade on, the runway is still flying anyway.
Hugo is an engineer with strong technical expertise. Multilingual from an early age, his writing combines technical clarity with a strong interest in science and energy.
