In early prototypes of the A-10 Warthog, the 30mm main gun was mounted slightly offset from centerline, so the front landing gear could be mounted in the centerline.
-Test pilots complained that it was impossible to fly the A-10 straight while firing the main gun. The main gun was so powerful that it turned the plane.
-Engineers solved the problem by mounting the main gun exactly on centerline, requiring that the front landing gear be mounted off the centerline, making steering more difficult. its been that way ever since.
