@Erich_L I see. Why bother launching individual oranges at mach 5 when you can launch entire fruit factories. Think big! Shoot for the stars! :D
Seriously, though, constant velocity does not produce any forces, regardless of its magnitude. Think about second Newton's law; the force is proportional to the velocity change over time: F~dv/dt. No velocity change, no force. Inside the factory traveling at steady mach 5, things would behave exactly the same as if it was standing still. If there were no windows, no fruit inside would notice any difference.
As others already stated, you need to accelerate incessantly if you want to produce a gravity-like constant force. This was in fact one of starting premises for Einstein's concept of gravity. He postulated that gravity doesn't really need to exist (as intrinsic property of mass), but can rather be seen as a result of permanent acceleration...
However producing such force using acceleration is not really feasible in a computer simulation. Even if you magically fix all the precision problems caused by enormous movement distances between simulation steps, the velocity magnitude will have reached computer's numeric limits shortly after the simulation start.
But why do you even consider this? Simply adjust the gravity force by clicking buttons in Godot, and let the narrative do the rest. Tell your players the factory is now parked in lower Alderaan orbit, with current gravity stabilizing at pleasant .6g
