I should probably spend a bit of time and show what we do. Over the past couple of years, the company I work for as been actively broadening their horizons to include other types of work than heli-logging. I thoroughly enjoy the other work but it is fair to say that our bread and butter work is logging. Basically, heli-logging is done two different ways. The typical method is what we refer to as 'hook logging.' These days 'grapple logging' is becoming equally as common. I will explain both methods in more detail with pictures. When we are using either method or combination of, we will use either a water drop zone or a land drop zone. Both have advantages and disadvantages.
Hook logging makes use of cable chokers and ground crew (riggers) to build loads for the helicopter to fly. The chokers are wrapped around the logs and the rigger puts the chokers into the hook on the end of the line below the helicopter in order for the logs to be flown to the landing. The riggers use their knowledge of log types, log grades and log weights to determine which logs fly and how many they can build into one 'turn' for the helicopter to take at one time. The Boeing Vertol that I fly has a maximum load capacity of about 10,000 pounds at the the end of the fuel cycle. At the beginning of the fuel cycle we take about 2,000 pounds less because we are carrying that much extra fuel in order to stay airborne for an hour and a half. We always use a 200 foot line below the helicopter unless we are in particularly steep ground with tall trees, then we add length to the line. The hook has evolved from being a true hook to becoming a nubins hook. The chokers no longer have 'eyes' spliced at the end of them, they use a steel 'nubin' to go into the jaw of the hook. In this picture I am pointing to the nubin with the hook in the background. The hook weighs 130 pounds. The white marshmallows in the background are floats on the chokers for water drop. Hook logging has some very obvious advantages when it comes to production. A good rigging crew is able to keep the amount of wood flown per hour as high as possible by rigging maximum weight loads. Some of the disadvantages are having people working so close to the danger area of shifting logs during yarding and the danger area of the drop zone.
Grapple logging uses the same 200 foot line but instead of a hook there is a 1,000 pound hydraulic grapple attached to the line (see picture). The pilot controls the grapple from the cockpit and is responsible for building his own loads by putting multiple logs together. A small ground crew goes ahead of the helicopter and uses paint marks to designate what logs are to be flown and to give a general idea of log weights.
A water drop zone is bar far the fastest way to drop the logs and with very little breakage. I understand there can be some environmental downsides to the water drop as it disturbs the marine life in the area. We tend to log mainly in remote inlets with no road access and the wood ends up in the water in order to be be boomed and barged to the sort in the lower mainland. The following picture shows a typical water drop zone. There is usually two boom boats 'chasing' the chokers from the logs where they are coiled again on the choker float to be returned to the riggers. When dropping the logs on land, there is either a wheel loader or log loader in the landing to pile the logs and load logging trucks. Two chasers on foot run in to retrieve the chokers after the logs have been released in the landing by the helicopter. In general terms the water drop is safer for the chasers because the logs are not landed nearly as close as during a land drop. Much less room for error during land drop operations.
So I guess that's the basics of how heli-logging works. I have simplified much of it and I can always go into much greater detail but risk boring you all to death. It is a very challenging profession as a pilot. We spend hours flying looking straight down. And in a usual logging day the aircraft is in the air for 11 hours. Each pilot usually logs 7-8 hours. Constantly changing conditions on the coast can be very challenging to deal with. This morning we saw fog, rain and wind and had to land several times to allow squalls to pass. It never ceases to amaze me how hard it can be to get back into the groove of logging after even a short break from it. Through it's challenges and sacrifices of being away from home it is a rewarding career. On nice days the view from our office can't be beat!
Grapple logging uses the same 200 foot line but instead of a hook there is a 1,000 pound hydraulic grapple attached to the line (see picture). The pilot controls the grapple from the cockpit and is responsible for building his own loads by putting multiple logs together. A small ground crew goes ahead of the helicopter and uses paint marks to designate what logs are to be flown and to give a general idea of log weights.
A water drop zone is bar far the fastest way to drop the logs and with very little breakage. I understand there can be some environmental downsides to the water drop as it disturbs the marine life in the area. We tend to log mainly in remote inlets with no road access and the wood ends up in the water in order to be be boomed and barged to the sort in the lower mainland. The following picture shows a typical water drop zone. There is usually two boom boats 'chasing' the chokers from the logs where they are coiled again on the choker float to be returned to the riggers. When dropping the logs on land, there is either a wheel loader or log loader in the landing to pile the logs and load logging trucks. Two chasers on foot run in to retrieve the chokers after the logs have been released in the landing by the helicopter. In general terms the water drop is safer for the chasers because the logs are not landed nearly as close as during a land drop. Much less room for error during land drop operations.
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