At the beginning the ropes were made of twisted hemp. Nowadays the so called "ropes" are actually polyester endless round slings of variable length. For the transportation of logs (logging) the helicopter companies usually use chocker cables. The cable suspended to the ventral hook of the helicopter can have a variable length. Some of these cables, as for example, the "long line" used for logging operations, are electrically released by the pilot.
Nets and bags
The net is a widely used equipment. On the market there are nets of different sizes. The biggest are usually used to transport hay from the mountains to hay-lofts. The others are used to transport supplies, equipments, furniture, firewood, etc. Modern nets are made with synthetic materials and are extremely light and resistant.
At the beginning the four extremities of the net (button-holes) were directly hooked to the cargo sling. In this way the pilot could, for example, take-off and take advantage of the ground-effect and evaluate with precision his height over the ground.
Nowadays to save time and money helicopter companies suggest the use of the “heli-bag", a light big bag of variable volume made of polypropylene. With this equipment, which is usually sold with a nylon rope, the customer can calmly prepare his cargo. Heli-bags are now widely used for a large variety of transportations.