I know about the Galileo's law which says that in the vacuum the mass doesn't influence the falling speed of an object so that a feather and a stone will hit the ground at the same time, and that it is air resistance which actually makes objects of different masses fall with different speed.
And this is [cite]Ah, you can shift the COG by an additional mass inside the aircraft which cannot be seen from outside.[/cite] is what EvilSOB has already written above. And the "center of gravity" is actually waht I need. I am not trying to make a true-to-life simulation with all that aerodynamic behavior, well it whould behave like a plane but I want to keep it simple. And adding mass will increase the weight, the downward gravity force, which will make the plane fall with its nose first.
Anyways, Thank you for your replies laugh Any reply helps in some way.
Though I am not working on the plane fall right now(I could not make the constraints properly), since the thread was continued, I would like to ask an additional questions about the qonstraints: I saw that all types of constraints have the anchor point: is it the point wehre the two objects are welded? If yes, how to change its position? the anchor point has the coordinates (0,0,0) but are these coordinates: world coordinates, the coordiantes in relation to the object, or what? I tried to change them but the additional invisible object was always in the same place?
Here's how I did it
this was attached o the "adding weight object"
Code:
ENTITY* engine;
action engine()
{
	engine = me;
	set(my, PASSABLE);
	//set(my, INVISIBLE);
	phent_settype(my,PH_RIGID,PH_BOX); 
phent_setmass(my,0,PH_BOX);
 phent_setgroup(my, 2);
phent_setfriction(my,0);
phent_setelasticity(my,0,0); 
phent_setdamping(my,0,0); 
ph_setgravity ( vector(0,0,0) );
ph_fps_max_lock = 70;
}

and this was written in the plane action:
Code:
phcon_add(PH_BALL,my, engine);
phcon_setparams1(2,vector(0,50,0),nullvector,nullvector);

As you see, I have changed the anchor coords, but it didn't change the additional object's position, so I assume that the point to which it is welded has not changed either. So how to deal with this anchor point?
Thank you in advance

a generator of dull questions smile