David and Jean Hewitt were on the caravan park which adjoins Caernarfon Airport, when the crash happened yesterday morning.
They said the plane clearly appeared to be coming in too slowly and too low, and didn't reach the runway, but clipped trees and flipped over.
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A top health boss has told ITV News that change is needed to hospital services in north Wales, that could include A&E.
A fine and bright start to the week, with any lingering rain clearing away as we move throughout the afternoon.
A wet and windy night to come, with rain turning heavier overnight. Feeling particularly blustery in coastal areas.