At that time, calculating every natural frequency modes for that kind of structure might have been really complicated. Now with computers and Finite Element Analysis softwares, a 3D model and a few hours of convergence calculation and it's done.
@nealadamsdotcom - Plus, assuming you don't understand my formulas (and obviously don't want to understand it) you say that gravity attraction was 20% of what it is right now? that's 1/5 ....On moon it's about 1/6...pretty hard to believe...but i don't want to argue with you... i was simply askin...
At that time, calculating every natural frequency modes for that kind of structure might have been really complicated. Now with computers and Finite Element Analysis softwares, a 3D model and a few hours of convergence calculation and it's done.