An ode to Phipps' jeep convoys

The jeep problem was first solved by O. Helmer and N.J. Fine. But not much later, C.G. Phipps formulated a more general solution. He formulated a so-called convoy or caravan variant of the jeep problem and reduced the original problem to it. We shall refine the convoy idea of Phipps and subsequently view a more general jeep problem, which we solve for jeep convoys as well as for a single jeep. In the last section we solve Maddex' jeep problem.