I was on an AA flight this evening, and after 20 minutes at the gate, the captain announces the plane is Out of Service. Immediately, the guy in the window seat next to me jumps up and over me (literally), and in one motion opens the overhead and grabs his full-size (22") rollaboard. When he pulls the rollaboard out of the bin, he jerks it so hard it flies out and right on to the shoulder of the lady seated across the aisle. She yelps, and he tries to scurry off the plane.

A guy behind me says "wait a minute, you hit her!!" and the guy turns around, says, "Oh, sorry" and scampers off. At this point, someone (I'm guessing the guy who yelled that guy A hit this woman) gets up, runs out and comes back with guy a. Guy A gives a more sincere apology, but the damage has been done.

The woman who was hit by the bag is clearly in pain (as she was from the beginning) and asks for the gentleman's name and contact info...

That leads me to the question: "who is liable for any medical expenses incurred in this situation?" I mean, you drop a 30 pound bag on someone's shoulder, and it could do some damage (broken collarbone? Not sure - I'm not a medical professional).

Does the guy who dropped the bag pay? Does AA pay? Does the woman who was hit pay?

Not sure if someone has to pay... that's for the court to decide but I would guess that the Guy who dropped the bag on her shoulder is at fault. AA should not be liable.

Wirelessly posted (BlackBerry8703e/4.1.0 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/104)

As a general rule, a party who negligently causes injury to an innocent victim is liable for the injury caused. The victim might be entitled to recover damages for pain and suffering, medical expenses, and lost wages. If the negligent party has homeowner's insurance, the insurance might provide coverage for this situation.

Somewhat similar thread about alleged passenger negligence: Falling carry-on luggage can hurt!