Riders of the Timberline (1941)

Yates has hired Petrie and his men to stop logger Kerrigan from fulfilling his contract. When Petrie's man Slade gets the loggers to quit, Kerrigan's daughter arrives with a new crew. When they destroy the flume, Hoppy builds an overhead line to transport the logs. Now desperate, Petrie sets out to blow up the dam and Hoppy takes to the overhead line in an attempt to get there in time to stop him.