Not Good!! The only incident I've ever experienced to date was coming back in to land at my home base last summer out of hours. After having done a low fly-by of the runway and broadcasting to 'Traffic' I set up my final approach. I noticed, at about 500' a car operating around the area of taxiway, nothing out of the norm here and carried on the approach keeping my spare eye focused on the car - I couldn't believe it as he edged closer and closer to the runway and then when I was less than 100' from touchdown (after crossed the numbers) he came straight out on the runway!! Full power and go around no big deal, but it opened my eyes as to how bloody stupid some people can be - he clearly never checked the approach!!
(Well I say 'he' - could have been a woman!
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