Main structural (and any other) impact of hard landing I was reading this question related to the parts suffering the most G forces. Reflecting about that question I question myself about hard landing, which is not a normal operation. 

So, my especific question is: when an airplane is suffering a hard landing event, which are the structural parts (and any other part that might not be structural and I might be forgetting) that are suffering the main damages and why? 

Will this answer depend on the airplane vibration mode (i.e. location of engine masses)?
here are the main parts at risk for structural integrity after a hard landing: 

the landing gear itself and the attachment points of the gear to the fuselage and/or wings

the fuselage-to-wing attachment structures

the engine-to-wing (pylon) or engine-to-fuselage attachment structures

the main fuselage structure in the immediate vicinity of the wing attachment points

If the hard landing involves a tail strike, then the integrity of the aft pressure bulkhead is at risk.

Note that the structural integrity risk is not simply one of prompt failure due to an overstress impulse load, but also subsequent premature fatigue failure arising from microcracks caused by the hard landing stresses- especially if that cracking occurs in a location which is inaccessible for inspection.