Definition of "tankwise"

The torque was "built up" in the special back axle and the car crawled tankwise but very certainly over the obstacles without a jar or hesitation.

1923, A. A. Hill, Automobile Dealer and Repairer, page 30

Would it not be true that even in the best possible light, we would be badly outnumbered tankwise in the event that conventional warfare broke out in Europe?

1963, United States. Congress. House. Committee on Armed Services, Hearings, page 779