So this stuck with me and I kept coming back to it..... and I think you are right and I was wrong (but may be getting 'righter' after shaking off my earlier, wrong, thinking).

First: launching into orbit, yep, the velocity is a 'freebie' and absolute regarding orbital velocity. I missed it because I was thinking about the entire flight (including landing) but that is irrelevant. All that is required is a fixed amount of acceleration to an altitude and velocity, and starting off going with the Earth's rotation would just add or subtract.

The second part is harder for me to see because I am stuck on the fact that 'force' would be lost at launch. And that is fine and well but does not mean anything if there is nothing trying to alter the projectile's initial velocity in the first place. This is what I think I missed or rather kept injecting but does not belong: there is a velocity added or subtracted, so what? Nothing external will exert any force on the projectile to reduce or increase that velocity! The entire path becomes So again, I think you are and were right and I was wrong- the Coriolis effect does reduce to zero as the angle approaches and reaches a direction parallel with the Earth's rotation, any line of latitude. This only applies at the equator but that is what we have been talking about.

Moving away from the equator makes it more complex because I do not think there are any 'straight' lines of latitude anymore that will not cross a curve. Still thinking about that one though.

So thanks for the input and correction- it is always best to be correct as much as can be. Your insomnia turned into my.... afternoonstuckinthethought onmia.

I did go looking for calculating 'accessories', formulas, a spreadsheet or similar but everything I found is commercial and has to be purchased. So much for the easy way out of 'plug 'n chug' calculating. Going to have to do this the hard way and work with the rules and physics.

Thanks again!

Brian

Interesting. I will have to study the Eötvös Effect more. This is why NASA launches to the east the vast majority of the time. Extra 1000 mph is a lot of rocket fuel.

But I still maintain that the Coriolis Effect is near zero at the equator and more pronounced at the poles due the the difference in the rate of angular movement. I did find a website that agrees with me:

https://www.quora.com/Why-is-the-Coriolis-force-zero-at-the-equator-and-maximum-at-the-poles

The Coriolis force acts in a direction perpendicular to the rotation axis and to the velocity of the body in the rotating frame and is proportional to the object's speed in the rotating frame.

The Coriolis effect is caused by the rotation of the Earth and the inertia of the mass experiencing the effect. Because the Earth completes only one rotation per day, the Coriolis force is quite small, and its effects generally become noticeable only for motions occurring over large distances and long periods of time, such as large-scale movement of air in the atmosphere or water in the ocean. Such motions are constrained by the surface of the earth, so only the horizontal component of the Coriolis force is generally important.

The horizontal deflection effect is greater near the poles and smallest at the equator, **since the rate of change in the diameter of the circles of latitude when travelling north or south, increases the closer the object is to the poles.**

Hey! My insomnia fueled brain farts can't be wrong!