The two seat R22 has been produced since 1979. Manufactured by Robinson Helicopter, the Robinson R22 is a two bladed, single engine, light utility helicopter. Robinson R22 Aircraft Information.1500 TT, 1100 helicopter, qualified Twin Beech.Heli Air is the licensed UK Distributor of the full range of Robinson Helicopters the 2-seat Robinson R22, the 4-seat Robinson R44 and the 5-seat Robinson R66 Turbine, and also sells a large fleet of Bell, Eurocopter, Schweizer and Agusta Westland helicopters. The use of helicopters in forestry continues to expand.16mm SOUND-Projectors, Films, New, Used for Sale, Free Catalog. The empty weight is 796 lb (389 kg) and the maximum takeoff weight is 1370 lb (635 kg).Employed since the early 1950’s, helicopter yarding is incredibly versatile due to its ability to avoid many of the obstacles that encumber ground based and skyline systems, including site sensitivity, urgency to remove or deliver the product, lack of access, and slope of the terrain.Although there is no formal classification system, heavy lift helicopters are often considered to be those capable of lifting an external load of 15,000 pounds or more. Mechanical ConfigurationThe payload they are capable of lifting and identified as heavy lift, medium lift, or light helicopters typically categorizes helicopters. To overcome these costs the operations must maximize the amount of material removed per turn and minimize the time per turn. Helicopter logging typically requires two landings - a service landing for the aircraft to refuel as well as periodic maintenance - and a log landing for dropping off the extracted timber.Helicopter operations have high operational costs as well as high fixed costs for move in and out.The long line is typically between 90 and 300 feet in length, depending upon topography and the height of trees above which the helicopter must hover. In some operations, a grapple may be used instead of chokers. The size of helicopter appropriate for a particular application is determined by the size and value of the material being extracted.Helicopter logging is accomplished by suspending below the aircraft a long line of wire rope to which chokers can be attached.
One is used to accommodate an estimated reasonable payload of logs and the other is used as a ‘bonus’, to target the optimal payload. The hook commonly has two slots to accept chokers. The choker ends are then brought together to make up loads that are estimated as being slightly less than the helicopter’s lifting capacity.The chokers are attached to the long line by a hook. This results in some labor cost savings.There is a fuel truck and service truck at the service landing. The spotter guides the helicopter to logs requiring removal. The helicopter pilot controls the hook remotely.When a grapple is used instead of chokers, a spotter is required in the stand in place of choker setters. PersonnelThe number of personnel engaged in a helicopter operation will vary based on the size of the helicopter being used. If mechanical processing is occurring at the landing, there will be at least one processor present.A smaller helicopter may be used to ferry choker setters into remote locations and to deliver chokers. The other loader will be involved in loading trucks for transport. The hooker is responsible for building the required payload on the hook. Hooker - hooks a turn of choked logs to a hook suspended below the helicopter on the end of a “drop line” or “tag line”. Choker setters - pre-set chokers on logs to be extracted, working ahead of the helicopter so that they are not endangered by dropping logs and so that the helicopter does not have to wait while chokers are being set. This requires more loaders to move the material through the landing, more chasers to unhook turns, and more in-woods choker setters and hookers to prepare and hook the turns. During the hooking element there will often be a person, the hooker, on the ground with pre-choked logs. Beginning at the service landing, the helicopter will fly to the harvest area and begin yarding logs. Yarding CycleA typical flight cycle for a logging helicopter can be described as follows. It is often more cost effective to do the final bucking at the landing in order to maximize the payload of the helicopter. If processors are not used, chainsaw operators are usually required at the landing to trim excess branches and buck logs. There are also the loader and processor operators to handle the logs delivered to the landing. Forex best trend indicatorAt the landing the pilot sets the logs on the ground in the drop zone and releases the chokers from the hook. The helicopter then climbs vertically to lift the logs off of the ground and clear of the forest canopy.The inhaul element involves flying the load of logs from the hooking point to the landing. Then the hooker slides the chokers into the hook. The pilot locates the hooker and maneuvers the hook near the hooker. The service cycle refers to when the helicopter is flying to the service landing or is in the process of refueling or undergoing maintenance.There are some variations to this process. When the helicopter is in the outhaul, hooking, inhaul, or unhooking elements, this is called the flight cycle. The pilot must then return to the service landing for fuel. If no problems occur, this continues for 60 to 90 minutes, until the helicopter must be refueled. The hooking element begins again and the cycle is repeated. The entire process, outhaul, hook, inhaul, and unhook, is commonly referred to as a turn. The following equation can be used to estimate the adjusted average yarding distance as measured on a map (i.e., horizontal distance):Average Yarding Distance (adjusted) = (Elevation Difference )/0.28 Where, Elevation Difference is the difference in elevation between the log pickup point and the landing. When the direct flight grade exceeds approximately 28%, an adjustment is appropriate to reflect a more accurate yarding distance. The effective yarding distance for helicopter yarding is influenced by the elevation difference between the landing and the log pickup point, wind direction in relation to the approach to the log landing area, atmospheric conditions at the logging site, and obstacles such as hills and power lines that may require deviation from a straight-line flight path.Large differences in elevation between the landing and the log pickup point require increased flight distance to dissipate altitude safely on descent or to climb safely when flying to an uphill landing. Yarding distance is measured along the flight path of the aircraft and not necessarily along a straight line from the unit to the landing. Used Helicopter For Sale Usa Free Of TheIn large timber, logs may have to be split. Logs must be bucked so individual logs do not exceed the net lifting capability of the helicopter and all cuts must be complete so that each log is free of the adjacent one. In addition, the log bucker must consider the weight of the manufactured log. However, in a helicopter sale, a special effort must be made to bunch felled trees so that the logs can be bundled together by the hooker to meet the target payload.Logs are generally bucked to the lengths and grades desired by the processing mill. In partial cutting operations, protection of the residual stand is an important consideration in selection of the desired felling pattern. The timber should be felled in a manner that will minimize breakage. In sugar pine and other heavy species, butt logs from trees over 60" DBH may have to be split or cut to very short lengths. In general, even when the largest commercial helicopter is used for yarding, trees over 60" DBH will have butt logs shorter than 32'.
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