Mortar stabilizer test vehicle

Mortars fired with grading cylinders seem to be unable to hit the target and can only be used for recreation.
AG1 and AG2 control the firing of the main gun.
AG4, AG5 and AG6 control mortars,
AG4 starts mortars and stabilizers, AG5 switches to flat fire mode,
the firing order of mortars is ranked from 1 to 5, and AG6 starts to load the mortar once.
AG3 is used to control the auxiliary aiming system of the main gun and mortar, start and set the target, and the gun will calculate the elevation angle of horizontal shooting.
Note that AG5 is effective after AG3 is started.
The maximum pitch angle of the main gun is 15, and the elevation angle is 35.
Mortar depression angle is 90, without elevation angle.