The Case of the Airborne Invasion (Hank the Cowdog #81) by John R. Erickson

It's all hands on deck after head rooster J.T. Cluck files an alarming report that the Charlies have invaded the ranch! And, things go from bad to worse when, in the midst of the chaos, Drover turns up missing. Between J.T.'s report and some important clues from Pete, the Security Force has no choice but to assume that he's been taken hostage! Will Hank be able to rescue his deputy from the Charlies in time--or even find out where they're hiding him--or is it curtains for everyone's favorite sidekick?