I've been flying airliners for about one year and a half, over 1000 hours (on type) and probably in the region of 600 sectors. To give an idea of the frequency, in that time I've had four go arounds. Some people go years without experiencing one, but a lot depends on the airports you're operating to and from.
The first was when we were taking radar vectors to an approach: the controller turned us in too early, gave us too short a ground track, meaning we were too high on the profile. Despite doing everything we could to lose height we were unable to get back on the descent profile and went around at about 800ft AGL, before we reached the gate.
Next time, the preceeding aircraft didn't vacate the runway in time. We reach Decision Altitude (=200ft agl) before getting cleared to land, so no choice but to go around.
Third one was a good'un. On a Cat3 autoland in crap weather at night. Came out of cloud at about 60ft with the aircraft not aligned with centreline to our satisfaction. Decision height was 50ft agl and we initiated a go-around at minima. If you think that the aircraft is descending at 750fpm approx, the engines take a finite time to spool up and the aircraft has a lot of inertia, then the aircraft probably bottomed out at 15ft or so. I believe it's not unheard of for wheels to touch the tarmac on such Cat3 GAs.
Last one was an approach to an airport in the Alps with fairly high weather requirements due to the surrounding terrain. After starting the approach the mist thickened slightly, ATC reported a Runway Visual Range just below the minimum we required and therefore we had no choice but to go around.
Most passengers will never experience a go around, most of the rest may see it once. Due to their infequency very few members of the public will have seen it more than once. Because it is unusual and unexpected some will equate this to some sort of emergency but it is nothing of the sort. It is a standard manoeuvre, practiced ad nauseaum and often the result of utterly mundane causes. It is a high workload time for the crew and may surprise the passenger but that's about it.
Last edited by Torque Tonight; 14th Mar 2011 at 20:40.