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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Western areas will see the wet and windy stuff continue overnight! And then tomorrow - i'm very sorry to say - there is more of it to come!
Dolaucothi Gold Mines is among five locations battling it out to be crowned Wales' best place in this year's Special Places competition.
It's the latest in a series of incidents, despite safety measures being put in place after the death of an off-duty police officer in March.