The Coriolis force involves a rotating reference frame, the deflection is called the Coriolis effect.
As such, the proponents of a spherical stationary earth have been using Mach's Principle to state that distant rotary masses can cause local inertial forces, like the Coriolis and centrifugal forces, which perfectly mimic the inertial effects of a spinning Earth . This implies that there are two possible explanations for the inertial forces whenever objects are in relative rotational motion.
The experiment performed by J. Barbour and B. Bertotti proved that a large hollow sphere (representing the distant star fields) rotating around a small solid sphere inside (modeling the Earth) produced exactly the same pattern of Coriolis and centrifugal forces that are claimed as proof of Earth's spinning in space. If the hollow shell of matter accelerates or rotates, any object inside the shell will tend to be carried along with the acceleration or rotation to some extent. There have arisen some questions re: the Lagrangian used by Barbour and Bertotti and also about the coordinate transformations discussed in their article, but the main experiment showed, quite clearly that Mach's Principle is correct.
http://www.freelists.org/post/geocentrism/Overview-Barbour-BertottiHowever, for a Flat Earth, a much more complex explanation is needed.
We need to compare the Coriolis effect to something else which is also affected by a rotating reference frame: the propagation of light in rotating systems.
One of the greatest physicists of the 20th century, on the same level with Einstein and Lorentz, Dr. Ludwik Silberstein, has derived the exact formula for the Coriolis effect on counter-propagating waves:
https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2068289#msg2068289Here it is:
4AΩ/c^2
The same derivation/formula for the Coriolis effect on counter-propagating light beams:
https://www.ias.ac.in/article/fulltext/pram/087/05/0071The Coriolis effect is a PHYSICAL EFFECT upon the light beams: the phase shift will be caused by the physical modification of the light paths (inflection and deflection due to the Coriolis force effect on the light beams).
The Sagnac effect is an ELECTROMAGNETIC EFFECT upon the velocities of the light beams.
Then, we can compare the Coriolis effect to the SAGNAC EFFECT on the light beams, using the Michelson-Gale experiment.
https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2070082#msg2070082 (Sagnac effect vs. Coriolis effect mystery solved)
Here is the correct Sagnac effect formula for an interferometer located away from the center of rotation:
To obtain the Coriolis effect phase shift, we substract the phase differences for each separate segment.
This formula is proportional to the area and the angular velocity.
To get the Sagnac effect phase shift, we have to add the phase differences for each separate segment
This formula is proportional to the linear velocity (and the radius of rotation), and will feature the addition of the two separate speeds and segment lengths. We can average the lengths and the velocities, to get a final formula which features one length and one velocity.
This is the great omission in the calculation done by A. Michelson.
Instead of adding the phase differences to get the true Sagnac effect, he substracted the phase differences and obtained the formula for the Coriolis effect.
Michelson and Gale recorded/registered ONLY the Coriolis effect, but not the rotational Sagnac effect.
This means that the physical deflection of the light beams was due to the ROTATING ETHER DRIFT FIELD over the surface of the flat earth.
It is not the Coriolis effect that the RE have to worry about in the case of a speeding bullet, they have to explain the DEPALMA EFFECT on the projectile:
https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2029817#msg2029817 (DePalma spinning effect on long distance projectiles, part I)
https://www.theflatearthsociety.org/forum/index.php?topic=30499.msg2032069#msg2032069 (part II)