It was a parasol wing monoplane with a wing that was almost constant in plan out to the ailerons where the trailing edge began to curve in towards rounded tips.
Researchers fired rockets trailing conductive wires into thunderclouds to trigger lightning strikes, which were then analyzed by instruments carried on the ship's deck.
The problem arose as a result of insufficient sideward freedom of movement of the trailing axle when the locomotive traversed sharp curves and turnouts.