Can anyone explain the ending of the novel Station 11 to me?
I enjoyed it but was a little confused. Is Station 11 a metaphor for the airport?
No. Station Eleven is a metaphor for the way in which the world has collapsed after the apocalypse and the dream that they'll somehow be able to get home (to an undamaged Earth). The irony, and indeed the central conceit of the book is that there's no way to get back to what they had before.
There has been a schism. There are people who, after fifteen years of perpetual twilight, long only to go home, to return to Earth and beg for amnesty, to take their chances under alien rule. They live in the Undersea, an interlinked network of vast fallout shelters under Station Eleven’s oceans. There are three hundred of them now.
The ending of the book finds the "traveling symphony" have made their (temporary) home in an abandoned airport and our hero is reading the titular comic, staring out of the window at the mothballed airplanes and longing to return to the old days:
Clark looks up at the evening activity on the tarmac, at the planes that have been grounded for twenty years, the reflection of his candle flickering in the glass. He has no expectation of seeing an airplane rise again in his lifetime, but is it possible that somewhere there are ships setting out? If there are again towns with streetlights, if there are symphonies and newspapers, then what else might this awakening world contain? Perhaps vessels are setting out even now, traveling toward or away from him, steered by sailors armed with maps and knowledge of the stars, driven by need or perhaps simply by curiosity: whatever became of the countries on the other side? If nothing else, it’s pleasant to consider the possibility. He likes the thought of ships moving over the water, toward another world just out of sight.