Transporting external loads

Eastern Montana Helitack hosted two A-219 "Helicopter Transport of External Cargo" courses this past week to train and re-certify firefighters in Miles City and the surrounding outstations. The course is designed to teach firefighters how to safely hook up external loads to helicopters. The most common external loads are sling loads, in which cargo is loaded into nets then hooked to the helicopter, and bambi buckets, which are used to drop water or retardant on fires. Both of these types of loads are either attached to a steel or synthetic long line which in turn is attached to the cargo hook on the belly of the helicopter or attached directly to the cargo hook of the helicopter. To hook a load to a long line the helicopter lowers the remote hook at the end of the long line to the ground and the ground personnel attach the sling load to the hook. The other option is to perform a hover hook up, such as in the video, where the helicopter hovers directly over the load and the ground personnel attach the load directly to the cargo hook.

While the hover hook up might seem more dangerous in that the helicopter is much closer to the firefighter hooking up the load, in some ways it is safer. Hover hook ups allow the helicopter to hover within heights of one half of the rotor diameter, also called Hover in Ground Effect (HIGE). This creates a cushion of air underneath the helicopter that allows the helicopter to maintain a hover using less power. Additionally, if the helicopter were to lose power, it would only have to fall 5-10 feet before hitting the ground.

When a helicopter is hooking up a load to a long line it must hover at 50, 100 or sometimes 150 feet above the ground. This is a Hover Out of Ground Effect (HOGE) situation and requires considerably more power to maintain the hover. Additionally, if the helicopter were to lose power at that altitude it would have a difficult time performing an autorotation and land safely without power. I had hooked up long lines before but this was the first time I had performed a hover hook up. It was exhilarating. Standing still while the helicopter flies into a hover over you made my heart race and the rotor wash even from this small a helicopter was amazing. A very cool experience.