The speaker imagines being the aircraft itself rather than a passenger or crew member. The plane's metal skin becomes "my aluminium hide," and its frame becomes "my own bones." The pilot's voice on the intercom travels right through this body, and a flight attendant's boredom buzzes against the rivets like a trapped wasp. It's a funny, slightly uncomfortable image of being a machine that feels everything said inside it.
Then the mood lifts. The plane "rises hungry to exceed myself," banking away from the grids of suburban lights, where trees can only be guessed at as shadows. Far below, the speaker pictures a distant ancestor, a small tree-dwelling creature, answering the engine's roar with its own cry. That sound seems to come from the stars, from Cassiopeia. The poem moves from mechanical routine to a sense of wonder, linking human flight with the deep animal past. The tone is playful at first, then awestruck.