Mission engineers designed a sky crane maneuver, lowering Curiosity on nylon cords from a rocket backpack because the rover is too heavy to use the airbag system developed for earlier rovers. „We know it looks crazy,“ said Adam Steltzner of NASA‘s Jet Propulsion Laboratory (JPL) in Pasadena, leader of the team that developed the system. „It really is the result of careful choices.“ By designing the aeroshell enclosing Curiosity to create lift and be steerable, engineers were able to build a system that lands much more precisely instead of dropping like a rock.