There are one or two airfields where landing straight ahead is not a viable option once past the point you cannot land on the runway left (Southampton and bembridge spring to mind and I am sure other people can come up with a few). In this case a turn back should be preplanned and briefed including a look at all options such as a partial turn to land back on the airfield but maybe not all the way round to make the runway. This is a manoeuvre that, if you ARE going to use, needs to have been practised beforehand at height so you know just how fast and how low you need to get the nose and how much bank to use, also how far round you will get in the height available. I normally cover this on the UH Advanced PPL course, but as much to point out how difficult it is as to enable its use