U.S. Army Air Corps biplane prepares to drop bombs on 1935 lava flow

A U.S. Army Air Corps biplane is prepared for a mission to drop bombs on a lava flow advancing toward Hilo during the Mauna Loa 1935 eruption. Below the plane is one of 20 demolition bombs (center) dropped in an attempt to disrupt and redirect the Humu‘ula lava flow, and two of the 20 "pointer bombs" (left and right) that were used for aiming purposes.