A crane comprising: a front member capable of derricking; a backstop disposed on a rear surface side of the front member so as to limit a standing operation of the front member as the front member pivots upward from a horizontal position; an angle sensor configured to detect an angle of the front member ; an operation detection unit configured to detect whether or not the backstop is operated; and a controller configured to control a derricking operation of the front member , characterized in that in a case where the controller determines that the angle of the front member is equal to or larger than a predetermined angle, based on a detection signal output from the angle sensor , and determines that the backstop is not operated, based on a detection signal output from the operation detection unit , the controller is configured to stop the standing operation of the front member , wherein one end of the backstop is supported such that the one end of the backstop is attached to the front member , and the other end of the backstop is a free end such that the other end of the backstop is not in contact with a contact portion of the backstop before performing the standing operation of the front member and comes into contact with the contact portion in accordance with the standing operation of the front member , wherein the operation detection unit is configured to detect whether or not the other end of the backstop is in contact with the contact portion , wherein the controller is configured to determine that the angle of the front member is equal to or larger than the predetermined angle, based on the detection signal output from the angle sensor , and wherein the controller is configured to stop the standing operation of the front member in a case where it is determined that the other end of the backstop is not in contact with the contact portion , based on the detection signal output from the operation detection unit . a front member capable of derricking; a backstop disposed on a rear surface side of the front member so as to limit a standing operation of the front member as the front member pivots upward from a horizontal position; an angle sensor configured to detect an angle of the front member ; an operation detection unit configured to detect whether or not the backstop is operated; and a controller configured to control a derricking operation of the front member , characterized in that in a case where the controller determines that the angle of the front member is equal to or larger than a predetermined angle, based on a detection signal output from the angle sensor , and determines that the backstop is not operated, based on a detection signal output from the operation detection unit , the controller is configured to stop the standing operation of the front member , wherein one end of the backstop is supported such that the one end of the backstop is attached to the front member , and the other end of the backstop is a free end such that the other end of the backstop is not in contact with a contact portion of the backstop before performing the standing operation of the front member and comes into contact with the contact portion in accordance with the standing operation of the front member , wherein the operation detection unit is configured to detect whether or not the other end of the backstop is in contact with the contact portion , wherein the controller is configured to determine that the angle of the front member is equal to or larger than the predetermined angle, based on the detection signal output from the angle sensor , and wherein the controller is configured to stop the standing operation of the front member in a case where it is determined that the other end of the backstop is not in contact with the contact portion , based on the detection signal output from the operation detection unit . <EOS>