This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
Keywords from Image Description:
Curtiss NC four engine configurationdetail. Curtiss NC seaplane Plane number four of four built named NC sometime after the translatlantic test flight Visible is the fourth pusher engine which was added for that flight cropped version of same photo below other versions of this photo Image CurtissNCfourengineconfigurationaftertransatlanticflight