Closing a metal filing cabinet.
Dropping a cardboard box or on the floor.
Hitting two pieces of metal together.
Knocking on cockpit door and then opening it
Short bump of wooden table, movement on floor
Knocking a metal door hard, two sets of three hits
Knocking hard on glass window pane.
Many various bodyfalls on/into shrubs, dirt, metal, concrete, timber, mud, water, garbage, hard surface
Knocking on a wooden surface or door.
Dropping a cardboard box or tissue box on the floor.