A method for operating a multicopter experiencing a failure during flight, the multicopter comprising, a body; and at least four effectors attached to the body, each configured such that it can produce both a torque and a thrust force; and a control unit which can control the flight of the multicopter; the method comprising the steps of, identifying the failure wherein the failure affects the torque and/or thrust force produced by an effector; computing an estimate of the orientation of a primary axis of said body with respect to a predefined reference frame, wherein said primary axis is an axis about which said multicopter rotates when experiencing the failure during flight; computing an estimate of an angular velocity of said multicopter, wherein the angular velocity is the velocity at which the multicopter rotates with respect to an inertial frame; wherein the method further comprises using the control unit to carry out said step of computing an estimate of the orientation of the primary axis of said body with respect to a predefined reference frame; and to carry out the further step of controlling one or more of said at least four effectors, based on said estimate of the orientation of said primary axis of said body with respect to the predefined reference frame, and based on said estimate of the angular velocity of the multicopter, such that one or more of said at least four effectors produce a torque perpendicular to said primary axis, wherein the torque perpendicular to said primary axis causes said multicopter to move such that the orientation of said primary axis converges to a target orientation with respect to said predefined reference frame, and such that one or more of said at least four effectors produce a thrust force along said primary axis. a body; and at least four effectors attached to the body, each configured such that it can produce both a torque and a thrust force; and a control unit which can control the flight of the multicopter; the method comprising the steps of, identifying the failure wherein the failure affects the torque and/or thrust force produced by an effector; computing an estimate of the orientation of a primary axis of said body with respect to a predefined reference frame, wherein said primary axis is an axis about which said multicopter rotates when experiencing the failure during flight; computing an estimate of an angular velocity of said multicopter, wherein the angular velocity is the velocity at which the multicopter rotates with respect to an inertial frame; wherein the method further comprises using the control unit to carry out said step of computing an estimate of the orientation of the primary axis of said body with respect to a predefined reference frame; and to carry out the further step of controlling one or more of said at least four effectors, based on said estimate of the orientation of said primary axis of said body with respect to the predefined reference frame, and based on said estimate of the angular velocity of the multicopter, such that one or more of said at least four effectors produce a torque perpendicular to said primary axis, wherein the torque perpendicular to said primary axis causes said multicopter to move such that the orientation of said primary axis converges to a target orientation with respect to said predefined reference frame, and such that one or more of said at least four effectors produce a thrust force along said primary axis.