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On Thursday, March 9, 2017 at 9:52:34 PM UTC-5, David R Brooks wrote:

A howitzer fires, with elevation 45 degs. So the shell exits,
pointing
upward at 45 degs., spinning. When it hits the target, it is (to 1st
approximation) falling at 45 degs., but the spin should have kept it
pointing upward. This means it would be flying sideways-on.
This sounds wrong to me, but where is the error?\\

The shell flies with its axis in line with the direction that the
shell is moving.
So the shell starts out pointed up by 45 degrees , it flight path
changes and its orientation also changes. Since the shell is spinning
, changing the orientation causes it to precess. And the shell
changes from not only the angle up but also changes sideways. So a
shell with a clockwise rotation fired due west, will turn so it is
going south west.

And it gets worse. A shell fired due North in the Northern
hemisphere will go somewhat East because of the Coriolis effect.

Dan
==============

At the WW1 Battle of the Falkland Islands the Northern Hemisphere
Coriolis correction in the British firing tables didn't hurt their
shooting.
https://en.wikipedia.org/wiki/Battle...lkland_Islands

The link to Felix von Luckner in 'Outcome' is interesting.
English-language history omits a lot about our enemies, for instance
in German history Rome never fell, they rightfully inherited control.
https://en.wikipedia.org/wiki/Theoderic_the_Great
"Seeking to restore the glory of Ancient Rome, he ruled Italy in its
most peaceful and prosperous period since Valentinian.."

-jsw