Pilot experienced a massive asymmetric wing collapse at low altitude while flying over trees in turbulent conditions after descending from cloud layer. Successfully recovered without injury.
Turbulence
High — very likely identified
Pilot took off from Little Grandston Airfield in calm conditions (5 mph winds, 12°C, 85-91% humidity). First flight in UK after USA trip, last flight was October 13th. Climbed above clouds to around 1200 ft, enjoyed smooth conditions and had coffee above the clouds. Descended through a gap in the clouds to avoid carb icing concerns. After descending below cloud layer, encountered much rougher air. While flying low over trees, experienced a massive asymmetric collapse. Pilot was 'just above tree height' when the collapse occurred, describing it as 'quite a scary moment'. Successfully recovered from the collapse, climbed away from the trees to gain altitude, and continued the flight in smoother air at higher altitude. Completed the flight with a landing.
The collapse was caused by turbulent air conditions encountered after descending below the cloud layer. The pilot flew through or near clouds with high humidity (90%+), then descended and encountered rotor turbulence likely generated by surface heating and terrain (trees). The combination of low altitude flight over trees and turbulent conditions led to the collapse.
Not deployed
trees below
Mostly correct inputs while reacting
November 8, 2025
United Kingdom
Little Grandston Airfield
Footlaunch
Bulldog Spirit
Moster MY25 DS
BGD
Luna 3
20
Closed
5 mph at ground level, turbulent conditions aloft
Clear morning with clouds forming, 12°C, 85-91% humidity, 5 mph winds at ground level, sunrise conditions
Thermally active conditions with rising clouds, rough turbulent air near surface, smooth air at altitude above clouds
Well, a massive collapse there. Well, just took a fairly large collapse. Quite close to the ground. That was quite a scary moment actually. We're at Little Grandston Airfield. Winds 5 mph. Perfect conditions. 12° C, 85% humidity. First flight in the UK. Last flight was on the 13th of October. Today is the 8th of November. Flying the BGD Luna 3 on the Atom. Above the clouds we go. Only at 1200 ft. Now, if I go back down through the cloud, I may get carb icing. It's around 90% humidity plus cloud. Yeah, let's go back down. It's a lot rougher down here. A massive collapse there. Jesus. What a huge collapse. Might turn around here. Not liking that. Not liking that at all. Bloody hell. Quick collapse. Let's get some altitude away from these trees. Well, just took a fairly large collapse quite close to the ground. That was quite a scary moment, actually. I was flying over the trees and I thought was a bit bumpy and all of a sudden poof. I was only just above tree height. Yeah, it was pretty scary. Gear: Wing: BGD Luna 3 20m, Motor: Bulldog Spirit Moster MY25 DS