The N3N (N2S), a biplane used to train carrier pilots at the start of World War II was nicknamed the "Yellow Peril" in part because of a brightly colored paint job intended to alert everyone around that a novice pilot was flying it; and in part because the plane itself had poorly designed landing gear which gave it a tendency to "ground loop," that is, destabilize and cartwheel on landing. At the conclusion of World War II, the remaining stock of N2S's were transferred from active service to the Naval Academy, where they remained in service until 1960.