I believe it is an Airone 250 from the 50's. Same design as the larger and better known Falcone. However, the Airone has a smaller diameter flywheel. Depending on the photograph, you can generally see the top of the Falcone flywheel from the right side view as shown here. The flywheel itself is on the left side of the bike but you can see it through the frame spaces. I can't see any here, so I suspect it to be the smaller Airone. Fine specimen by the way. What's the back story?
Some images to show the flywheel issue:


I found another very subtle frame variation. Confirming it is an Airone 250.
Patrick Hayes
Fremont CA