Originally Posted by
PLeblond
Say we take an A320 with 146 seats and every passenger has a carry on weighing 12kg. Assuming only 1 carry-on and not a 'personal item on top of that. That's nearly 4,000 lbs above the centre of gravity and the centre mass. I for one would not want to fly on an airplane like that
Perhaps this should be considered before we see another Midwest 5481... ???
I am not sure if I follow. There will always be some mass above the centre of mass, because the centre of mass is the "centre" where equal amount of mass is above and below it.
I think what you are trying to say is the vertical distance between centre of mass and aerodynamic centre. It does affect flight stability but it's not as simple as greater distance makes it "less safe". It's a balance between how easily the aircraft can roll vs how stiff the aircraft responses to rolling caused by external forces. Google "aerodynamic center" should yield some articles ranging from intuitive to mostly computational.
If you are worried about the effect of 4000 lbs of carry on luggage weight, keep in mind that an A320 can carry over 20,000 L of fuel which is 10 times heavier than all the carry on luggage combined, and most of which is below the centre of mass and aerodynamic centre, yet the aircraft is designed to handle this much weight variation.