Flying Bombs — Cora Buhlert

1936: A madman calling himself the Master of the Air threatens to let death and destruction rain down upon New York City. No one takes him seriously, until an airship taxi suddenly explodes the very next day. But was it an accident or sabotage?
Police Captain Justin O'Grady and the masked vigilante known as the Silencer both investigate the case. But it's a race against time, because the Master of the Air has already set his sights on a new target: The Zeppelin Imperator, the largest airship ever built…

This is a novelette of 8600 words or approx. 30 print pages in the Silencer series, but may be read as a standalone.