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.
More top news
A cloudy night with some patchy rain possible in places, clearer spells possible in the northeast. Milder than of late.
You've been sending us pictures of your children dressed up for World Book Day.
A brother is facing jail for killing his step-sister when she fell off a motorbike he was 'racing' in his car in December 2013.