Abstract: A method for automatically producing a defined face opening in a longwall mining operation in underground coal mining, using a face conveyor, at least one plow, as an extraction machine, guided on the face conveyor, and respective hydraulic shield support frames having, as main components, a floor skid arrangement, a gob shield, a top canopy and support connection rods. Inclination sensors are disposed on at least three of the floor skid arrangements, the gob shield, the support connection rods and a gob-side region of the top canopy. From the sensors, an inclination relative to a horizontal is ascertained.