the centerline. For an observer standing a beam, the frame has a "D"-shape. The D-Frame supersedes the outriggers and provides a good controlling angle on the guys. The Hallen derrick has a good purpose for e.g. containers, logs, steel rail, sawn timber and heavy lifts and doesn't lend itself for small, general cargo. It keeps the deck clear of guy ropes and preventors. Only one winchman is needed and within a few minutes the Hallen is brought into use. It is less expensive than a crane. A disadvantage is the low working range of the Hallen Derrick, it is able to swing 75° from the centerline and can work against a list of up to 15°. Velle The Velle derrick is quite similar to the Hallen but without use of outriggers. On top of the boom is a T-shaped yoke assembled. Also here, the guys serve for topping and lowering the boom but they are fastened on the yoke with four short, steel-wire hanger-ropes. The ends of the topping and lowering ends of the halyard are secured to half-barrels on one winch. In this way the boom moves in the same speed as the winch veers the topping end of the halyard and hauls the lowering end of the halyard, and vice versa. The slewing ends are also wound on to another half-barrel. For hoisting the cargo, there is a third winch to hoist to cargo on the yoke. Runners decrease swing and rotation of the cargo. A joystick duplex controller steers the Velle derrick. Stülcken The patent Stülcken derrick is used for very heavy cargo. It stems from the German shipyard HC Stülcken & Sohn which has been taken over later by neighboring yard Blohm & Voss. This derrick can handle up to 300 tonnes. The Stülcken can be made ready in few minutes, dramatically faster than a traditional heavy derrick, doesn't require much space and is operated by four winches. The Stülcken is secured between two V-shaped, unstayed Samson-posts. This makes it possible to let the derrick swing through the posts to reach another hatch. For each post is a hoisting winch, a span winch and a lever that is run by one man only. Bearings, swivels, sheaves and the gooseneck can be unattended for up to four years and create only a friction of about 2%. The span tackles are independent and the halyard is endless. With