A compound helicopter with at least one main rotor and a fuselage that extends along a longitudinal axis from a front fuselage section to a rear fuselage section, comprising: at least a first braced wing in joined-wing configuration and a second braced wing in joined-wing configuration, wherein the first braced wing comprises a first upper wing and a first lower wing which are interconnected in a first interconnection region, and wherein the second braced wing comprises a second upper wing and a second lower wing which are interconnected in a second interconnection region; and an emergency floatation system with main floatation balloons (14a, 14b, 15a, 15b) and lateral floatation balloons (16a, 16b), wherein the main floatation balloons (14a, 14b, 15a, 15b) comprise at least one front floatation balloon (14a, 14b) that is arranged in the front fuselage section and at least one rear floatation balloon (15a, 15b) that is arranged in the rear fuselage section, and wherein the lateral floatation balloons (16a, 16b) comprise at least one first lateral floatation balloon that is arranged close to the first interconnection region and at least one second lateral floatation balloon that is arranged close to the second interconnection region; wherein the at least one first lateral floatation balloon is mounted to the first lower wing and deployed toward the first upper wing in inflated state, or mounted to the first upper wing and deployed toward the first lower wing in inflated state; and wherein the at least one second lateral floatation balloon is mounted to the second lower wing and deployed toward the second upper wing in inflated state, or mounted to the second upper wing and deployed toward the second lower wing in inflated state. at least a first braced wing in joined-wing configuration and a second braced wing in joined-wing configuration, wherein the first braced wing comprises a first upper wing and a first lower wing which are interconnected in a first interconnection region, and wherein the second braced wing comprises a second upper wing and a second lower wing which are interconnected in a second interconnection region; and an emergency floatation system with main floatation balloons (14a, 14b, 15a, 15b) and lateral floatation balloons (16a, 16b), wherein the main floatation balloons (14a, 14b, 15a, 15b) comprise at least one front floatation balloon (14a, 14b) that is arranged in the front fuselage section and at least one rear floatation balloon (15a, 15b) that is arranged in the rear fuselage section, and wherein the lateral floatation balloons (16a, 16b) comprise at least one first lateral floatation balloon that is arranged close to the first interconnection region and at least one second lateral floatation balloon that is arranged close to the second interconnection region; wherein the at least one first lateral floatation balloon is mounted to the first lower wing and deployed toward the first upper wing in inflated state, or mounted to the first upper wing and deployed toward the first lower wing in inflated state; and wherein the at least one second lateral floatation balloon is mounted to the second lower wing and deployed toward the second upper wing in inflated state, or mounted to the second upper wing and deployed toward the second lower wing in inflated state.