Air Service Boys over the Atlantic

From the book:It means that fellow wants to ruin the Yankee plane, and perhaps finish the flier who went down with it to the ground. "Not if we can prevent it, I say. Take a nosedive, Tom, and leave it to me to manage the gun!""He isn't alone, Jack, for I saw a second skulker in the brush,I'm sure.""We've got to drive those jackals away, no matter at what risk. Go to it, Tom, old scout!" The big battle-plane, soaring fully two thousand feet above the earth, suddenly turned almost upside-down, so that its nose pointed at an angle lose to forty-five degrees. Like a hawk plunging after its prey it sped through space, the two occupants held in their places by safety belts.