you are going slow, and also you need to pitch trim, it looks like you need some flight training, very handy to use it, you will learn lots..oh and its not HDI (Heading Display Indicator) its the Atitude Indicator you are thinking of.. and no its not dangerous..its normal for slow flight

     -Erhan

I've noticed this too. I just remember to keep it just a little above the horizon line. You can also use the VSI to see if your flying level. If the dot is slightly above the line and the VSI indicates no climb then your level. Otherwise the only fix would be to edit the panel and put in another instrument or you could edit the instrument it'self but that takes some programming.

It's like when shooting you either use a coars or fine bead. In FS2002 you keep a very coarse bead on the artificial horizon.

The attitude indicator on the aircraft that i'm flying right now can be calibrated, but before each flight I make sure that it's set, which is easy cause i'm already level on the ground

The dot on the artificial horizon represents the nose of your aircraft in relation to the horizon.  If you are travelling at 70 knots with flaps down maintaining 2000ft altitude and course 045 degrees you are flying straight and level.  You may require between 5-10 degrees nose up to achieve this, thus the dot on the artificial horizon will point between five and ten degrees above the horizon line.  If you then wish to lose altitude you can drop your nose onto the horizon but you will gain some airspeed and your vertical speed indicator will deflect downwards.  You will not be flying straight and level at this point.

The artificial horizon, VSI, heading indiactor, turn co-ordinator, altimeter etc are all used together in instrument flying to determine the exact postion of your aircraft in the sky.  If you start trying to change what your instruments are telling you because you don't believe them you will soon crash.

Remember that it is possible to climb with the nose on the horizon and possible to descend in a nose up attitude.

Power + Attitude = Performance

Will

the dot on the ADI being above the horizon line is not inacurate,  most aircraft need to have a bit of nose up to maintain altitude, (unless we are talking B-52 which climbs with a nose down attitude) some ADI's are adjustable so you can zero your reference attitude. However changing conditions will also change this reference.  for example as fuel burns off the aircraft becomes lighter and will require less nose up trim to maintain altitude.  zeroing the ADI on the ground is of no use as it will of course change as you fly.  My suggestion is to learn where your references are and trust them, along with scanning the rest of your instruments, such as the VSI ( vertical speed indicator) and your altimeter.  This isnt dangerous, it's normal. once you understand what your instruments are telling you everythings cool.