MD83 and MD 87 Forward CG?

Question

Is there anyone else besides me who knows about this, so Mr smarty pants can eat crow?

MD 83s and MD 87s have a forward center of gravity, therefore baggage is always loaded aft first. 80-100 bags aft in an MD87, 100-120 bags aft in an MD 83.

I do know this to be true, I've loaded them 100 times. I just want someone who knows to back me up. List your source if you've got one.

Answer 1

Well, when the engines are in the rear, they move the wings farther back.  Rear engines do not make an aircraft tail heavy, compared to the wings.  If you are asking whether an aircraft is tail heavy or nose heavy, you have to tell us in relation to what.  I assume you mean in relation to the acceptable range of CG required to fly the aircraft.  With that in mind,  MD-83's and 87's are nose heavy when they are full of passengers.  When they are empty, they are tail heavy.  Many times they need foreward ballast to fly around empty.  When full, they do sometimes need to move people or bags aft.  So, both answers are correct.

Answer 2

All aircraft have a forward cg. The forward and aft MAC, mean aerodynamic cord, limits on an MD80 series are about 23.5% forward and 28% aft on the typical MD80. That is within one percent of every sweptwing jet, 737 for instance, ever certified under FAA part 25, certification for transport category. You dont see a particularly large elevator do you on an MD80. Why? Because it doesn't require more elevator to lift the nose that's any larger than a 737s elevator. Why, because relitive to the center of pressure, it's no more nose heavy. The same is true reletive to the main landing gear. Do you see those two really big round things on the back. Those are what's called very heavy motors. Now that's alot of weight aft for a heavy forwad cg airplane dontchathink? Why don't you list your source. Mine are the MD80 and 737 AFMs. Ever read one. That's where you find acurate weight and balance info.

As far as loading baggage, an aft cg is desirable for any aircraft so they are all loaded from aft forward up to the aft limit beyond which dynamic instability in the pitch axis would occure. In fact the concord had pitch trim fuel tanks so the cg could be moved aft during flight. Jeez man, you don't learn weight and balance by tossing bags into 100 aircraft.

Of course they move the wing back with rear mounted engines. Landing gear too. You missed my point but that doesnt matter. And all sweptwing aircraft are nose heavy when loaded with passenges. It 's necessary because fuel will move the cg aft. This is all just to simple.