In February of this year the navigation community lost a major contributor to navigation — John Bortz. To many his name is best known in connection with “the Bortz equation” which easily deserves a note here to highlight its significance in development of strapdown inertial nav. Before his work in the early 1970s, strapdown was widely considered as something with possible promise “maybe, if only it could ever come out of the lab-&-theory realm” and into operation. Technological capabilities we take for granted today were far less advanced then; among the many state-of-the-art limitations of that time, processing speed is a glaringly obvious example. To make a long story short, John Bortz made it all happen anyway. Applying the previously mentioned equation (outgrowth of an early investigation of Draper Lab’s Dr. J.H. Laning) was only part of his achievement. Working with 1960s hardware and those old computers, he made a historic mark in the annals of strapdown. Still, importance of that accomplishment should not obscure his other credentials. For example, he also made significant contributions to radio navigation — and he spent the lst two decades of his life as a deacon.