Steps to Reproduce:
1. Set /gamerule minecartMaxSpeed to 1000
2. Create a rail circle to gain speed with a ramp to launch the minecart. Put a daylight detector or ask a guy to activate the lever for you.

3. Get into the minecart (an entity must get into the minecart for it to reach optimal speed, preferably a player so that he can observe the issue)
4. When the maximum speed is reached, if it is daytime, execute the command /time set night to activate the daylight detector.
Important precision : This installation + the use of a gamerule is not necessary, it is simply an effective and quick way to drop the minecart from a great height, it ensures that no matter the environment the bug is observable

Observed Results:
In his fall, the minecart stops pointing downward after a certain amount of time in the air.
202408221654.mp4
Expected Results:
The minecart should continue to point down and move forward in the air.

Precision:
This issue requires the new minecart improvments experiment on.

Personnal assumption for the mods:
This bug may be linked to the bug "The minecart points downward after a small fall".