1907, from air (n.1) + plane (n.1); though the original references are British, the word caught on in American English, where it largely superseded earlier aeroplane (1873 in this sense and still common in British English). Aircraft "airplane" also is from 1907. Lord Byron, speculatively, used air-vessel (1822).
1. The insured value of the airplane was greater than its book value.
2. He slipped and fell on an airplane gangway as the cameras rolled.
3. They arrived in Belgium by airplane .
4. The ailerons on an airplane are hinged to the wing.
5. Flying in an airplane was a new experience for her.