The main undercarriage in a jet is almost always behind the axis around which the aircraft pitches
Chimbu, I would hope so! Given that an aircraft pitches about its lateral axis which runs through the CoG, if the CoG was aft of the main wheels the aircraft would sit on its tail on the ground. I think the main wheels on ANY aircraft that's correctly loaded are aft of the CoG. The longer moment arm between the CoG and the main wheels on a jet leads to the problem you've described, not the fact the CoG is ahead of the wheels.