Roy, this was *very* interesting! Thanks for sharing. :-) 73 Mike W0BTU
On Sun, Jun 6, 2021, 3:04 PM Roy Morgan <[email protected]> wrote: > Topbanders interested in laser measurements, > > Here are some short stories. During the time I worked at NIST (formerly > NBS), I heard about these situation: > > The David Taylor Model Basin (since renamed) has a water-filled tank about > 5/8 mile long for towing of scale models of ships to measure their > performance. A team from the mechanical metrology group at NBS measured the > flatness of the rails that carried the instrumented platform along the > tank. Their laser measurement systems found the middle of the tank to be > about 5/8 inch above the expected straight line end to end. It was the > curvature of the earth causing the “bulge”. > > At a presentation to aircraft manufacturers about measurement systems > being developed to more accurately make the major components of commercial > aircraft, many of which were being made at different locations, the speaker > noted that the Boeing 747 was assembled with shims to compensate for > differences between major parts that had to fit together (wings, fuselage > sections). “The 747 has a ton of shims”, he’d said. “Wait a minute”, one > Boeing engineer said, “How much do all those shims weigh?” About a ton, > was the reply - nearly two thousand pounds. And that weight gets carried > by the aircraft throughout its life. > > The NIST metrology building houses a highly accurately located GPS > receiver to develop error information that is broadcast by radio (and > presumably internet) useful for land surveyors to correct their laser > surveying instrument results. (One of the US’s primary geolocation points > is on the NIST grounds and forms the basis for all surveying done in the > Eastern part of the continent.) > > > > On Jun 6, 2021, at 12:58 AM, Richard (Rick) Karlquist < > [email protected]> wrote: > > > > I am considering replacing my 100 meter tape measures with > > a Bosch GLM400CL laser distance meter to use for laying out > > my next 160 meter circular array. I am wondering if anyone > > has any experience with this model or any other models that > > work to a range of 100 meters. (That spec eliminates the vast > > majority of meters). How important are accessories like > > tripods and target cards? > > > > 73 > > Rick N6RK > > _________________ > > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > > Roy Morgan > K1LKY since 1958 > [email protected] > Western Mass > > > > > > _________________ > Searchable Archives: http://www.contesting.com/_topband - Topband > Reflector > _________________ Searchable Archives: http://www.contesting.com/_topband - Topband Reflector
