From Wiki:
US Airways Flight 1549 is a classic example of this. The engines on the Airbus A320 used on that flight were torn apart by multiple bird strikes at low altitude. There was no time to make a safe landing at an airport, forcing a water landing in the Hudson River.
Jet engine intakes are very delicate things (wrt bird strikes) compared with a locomotive windshield and especially the surrounding metalwork:
Jet engine ingestion is extremely serious due to the rotation speed of the engine fan and engine design. As the bird strikes a fan blade, that blade can be displaced into another blade and so forth, causing a cascading failure. Jet engines are particularly vulnerable during the takeoff phase when the engine is turning at a very high speed and the plane is at a low altitude where birds are more commonly found.
It is the bent frame and several dents that make me think of heavy debris such as rocks/concrete/ice rather than bird strike.
