Conquest of the Air, The

A series of five 150 piece plywood puzzles, plus one larger 200 piece example, all thought to date from the late 1920's to early 1930's.
The series is called The Conquest of the Air, which was a feature in the Popular Flying publication.
See Page 32+33 of this Crazy-Cut catalogue for further details.
These excellent puzzles seem to be very scarce, and I would welcome further information and photographs from you, if available. Thankyou.