hard landings
I read somewhere that planes are designed to withstand a "dead drop" from 6 feet or a 600 fpm impact with the runway.
It is entirely possible that you witnessed a bad landing...they do happen! even in big jets.
I recall having a new copilot making the landing in a 737. I asked him what his previous flying job was. He told me that his previous job was as an f/o on a DC8. I watched closely, though DC8 experience is a good thing.
He didn't start a round out (flare) at the normal position...nothing...nothing... nothing, then he pulled the yoke back about 8 inches! rapidly and with great force. We simultaneously hit the ground and "bounced" back into the air!
I grabbed the yoke, added some power and made the second landing on that approach.
we got to the gate and I asked him what he thought of his landing. he went into the standard bit about wanting to "learn" and for me to help him. I told him he needed more IOE (initial opeating experince) training.
so, you may have seen a bad landing. going around is also a fine solution to a bad landing in many cases.
I also watched an MD80 (from the vantage point of another plane) porpoise down the runway. new type of plane, new copilot, unwillingness to "go around".
If a hard landing is done, a write up and mx inspection is usually required. One can recognize a hard landing by the deployment of all oxygen masks, or having the flight attendent come to the cockpit with her panty hose down around her ankles (kidding !)
I also know of one case in which the loading was not accuratley computed and the plane landed at 20 knots below the correct Vref speed. The landing gear punched a hole in the wing.
Things happen. Don't let them happen to you!
jon