Girls !
It is really to do with what you want to track !!
If you have a fleet of Fifty aircraft flying 300 hours a month that is a totally different requirement than if you have a couple of bizz jets flying 100 hours a month.
It also depends on how much manpower you have
You can certainly manage tech data for several aircraft ( and we do!) with MS Excel.
The spares side is a little more complicated !
