[gcompris-devel] Question in submarine

[pgeorges]

Bruno Coudoin wrote:
> Pascal, 
> 
> I still don't understand how the middle tank works and what it is use
> for.
> It is strange because it works the oposite way than the 2 main tanks.
> Opening the top valve add more air in the middle tank while it remove
> air in the 2 main tanks.
> 
> I suggest to simply remove the middle tank since it adds confusion to
> the submarine and it is not mandatory to understand the whole picture,
> nor to operate it.
> 
> Bruno.

The two main tanks have no accurate values. When you let air go out by 
opening the top valves, you can only guess what remains in them.
They are usually used in the same way :
- dive by opening both valves a long time;
- surface by flooding air (of course with valves closed - it is 
forbidden to navigate with valves opened !).

One special case is when you want to make an emergency surfacing : then 
you only flood air in the front tank (15 sec) to get a positive angle as 
quickly as possible. Then use both tanks.

The central tank is used to balance the submarine. The value shown is 
the water you have in. If you open the top valve, water goes into the 
tank, not air (because there is no pressure), and you should see it 
dives (if the main tanks have no air into). This is where you 
misunderstand how it works.

I'm sorry not to participate more to gcompris, but I tried my best to 
understand Gnome APIs and found nothing less usable in 10 years of IT !
So I really got fed up.

Pascal