Much of Doris Lessing's earlier work is based on her experiences in Africa. The main aspects of Flight could take place almost anywhere - because the story concentrates on relationships within a family - but the story is clearly set in Africa. There is also a lot of detail that seems to reflect Lessing's English roots, such as cups of tea and sewing.
The story may echo what happened in Lessing's own life: the young girl is desperate to leave home (just like Lessing was) and argues with her grandfather (perhaps like Lessing did with her parents). Even the grandfather's bitterness (he dislikes Steven and feels abandoned by his family) might reflect the views of Lessing's father.