A launching device for launching a first underwater running body (1.1) from a platform, in particular from a watercraft, wherein the first underwater running body (1.1) comprises a first propulsion unit (Tw.1), which is designed to emit a propellant (Tr.1), wherein the launching device comprises a first ramp (3.1), which extends along a first longitudinal ramp axis (La.1), wherein the first ramp (3.1) is designed (1.1) - to enclose and hold the first underwater running body (1.1) under water and - to guide it during its launch, dependent on the orientation of the first longitudinal ramp axis (La.1), wherein the launching device comprises a propellant deflection unit (4, 5, Km, Ka), wherein the launching device is designed to activate the propulsion unit (Tw.1), or to allow its activation, while the first underwater running body (1.1) is enclosed and held in the first ramp (3.1) under water, wherein the first ramp (3.1) is designed to direct propellant (Tr.1) emitted by the first propulsion unit (Tw.1) to the propulsion deflection unit (4, 5, Km, Ka), and wherein the propulsion deflection unit (4, 5, Km, Ka) is designed to divert emitted propellant (Tr.1) into an outlet direction (AR.T), which is directed perpendicularly or obliquely away from the platform; and the launching device is designed in such a way that water can penetrate into the or each ramp (3.1, 3.2); characterized in that the launching device comprises a first ramp flap (6.1), which in a closed state closes the first ramp (3.1) with respect to surrounding water, wherein the launching device is designed to open the first ramp flap (6.1) and thereby allow water to flow into the first ramp (3.1) before the launching device activates the propulsion unit (Tw.1) of the first underwater running body (1.1). wherein the first underwater running body (1.1) comprises a first propulsion unit (Tw.1), which is designed to emit a propellant (Tr.1), wherein the launching device comprises a first ramp (3.1), which extends along a first longitudinal ramp axis (La.1), wherein the first ramp (3.1) is designed (1.1) - to enclose and hold the first underwater running body (1.1) under water and - to guide it during its launch, dependent on the orientation of the first longitudinal ramp axis (La.1), - to enclose and hold the first underwater running body (1.1) under water and - to guide it during its launch, dependent on the orientation of the first longitudinal ramp axis (La.1), wherein the launching device comprises a propellant deflection unit (4, 5, Km, Ka), wherein the launching device is designed to activate the propulsion unit (Tw.1), or to allow its activation, while the first underwater running body (1.1) is enclosed and held in the first ramp (3.1) under water, wherein the first ramp (3.1) is designed to direct propellant (Tr.1) emitted by the first propulsion unit (Tw.1) to the propulsion deflection unit (4, 5, Km, Ka), and wherein the propulsion deflection unit (4, 5, Km, Ka) is designed to divert emitted propellant (Tr.1) into an outlet direction (AR.T), which is directed perpendicularly or obliquely away from the platform; and the launching device is designed in such a way that water can penetrate into the or each ramp (3.1, 3.2); characterized in that the launching device comprises a first ramp flap (6.1), which in a closed state closes the first ramp (3.1) with respect to surrounding water, wherein the launching device is designed to open the first ramp flap (6.1) and thereby allow water to flow into the first ramp (3.1) before the launching device activates the propulsion unit (Tw.1) of the first underwater running body (1.1).