A cargo hook is a device suspended below a helicopter and allows the transport of external loads during flight. Common terms for this operation include slingwork, underslung loads, external loadwork, and external load operations.
Primary, or "belly", hooks are designed to mount directly to the airframe belly, i.e. underside, of a helicopter. Because they are attached to the fuselage, or "skin," of the aircraft, belly hooks are regulated by the various worldwide aviation regulatory agencies. In the United States, belly hooks are governed under Federal Aviation Administration (FAA) FAR Part 133. [1] Belly hooks are designed, manufactured, and approved for use on specific aircraft models. Belly hooks that have been certified by the FAA receive a Supplemental Type Certificate (STC) [2] that describes the aircraft models that are authorized to use the hook for external load operations. For example, a belly hook approved for use by the FAA on a Eurocopter AS350 could not be used on a Bell 407 helicopter unless covered by the STC.
For small to mid-size utility helicopters performing external load work, belly hooks are typically mounted to the fuselage using either a sling or a suspension configuration. The sling mount uses a single attachment point, whereas a suspension system uses four attachment points. Since suspension systems transfer the weight of the cargo load across a larger swath of the aircraft, they can carry heavier loads than sling mounts.
Remote hooks are suspended beneath the belly hook by a long line, swivel, or other device. Because they are not attached directly to the airframe, they do not require aircraft-specific certification and can be used on a wide variety of helicopter models.
Key components of a cargo hook include the load beam, the keeper, and the attach point. The load beam is the solid piece of metal at the bottom of a cargo hook that supports the load. Usually it has a curved, narrow end which is used to load a ring, rope, or net onto the hook. The keeper is the locking, spring-operated mechanism that keeps the load from sliding off the load beam during transport. The attach point attaches the hook to the belly of the helicopter, swing system, or longline.
The following table includes a list of helicopter models that are designed to carry underslung loads. [3] Cargo capacities provided reflect the airframe manufacturer's specifications; when put into practice the actual maximum load capacities may be less, depending on the rating of the cargo hook equipment. For example, if a helicopter model is rated by the manufacturer as having a maximum cargo sling load capacity of 4,000 lb, but the cargo hook equipment is only rated for 3,000 lb, then the pilot can only carry loads weighing 3,000 lb or less.
| Manufacturer | Model | Slingload Cargo Capacity (lb) |
|---|---|---|
| Sud Aviation | Alouette II - SE 3130, SA 313 | 2,500 |
| Sud Aviation | Alouette III - SA 316-319 | 1,650 |
| Aerospatiale/Eurocopter | AS 350/355 | 2,557 mounted directly to airframe 3,086 on swing suspension |
| Aerospatiale/Westland | SA 330 Puma | 7,055 |
| Agusta | A109 | 1,500 |
| Bell | 204/UH-1 | 4,000 |
| Bell | 205/UH-1H | 4,000 |
| Bell | 206 Jet Ranger/OH-58 | 1,500 |
| Bell | 206 Long Ranger | 2,000 |
| Bell | 212 | 4,000 |
| Bell | 412 | 4,000 |
| Bell-Boeing | V-22 Osprey | 15,000 |
| Boeing/Vertol | CH-47 | 28,000 |
| Bristol | Bristol Belvedere | 5250 |
| Eurocopter | EC145 | |
| Hindustan Aeronautics Ltd | DHRUVS ALH | 3,300 |
| Kaman Aircraft | K-MAX | 6,855 |
| Kamov | KA-32 | |
| MD Helicopters | 369D/E, 500N | 2,000 |
| MIL | MI-6 | 17,650 |
| Leonardo | AW139 | |
| MIL | Mi-8/MI-17 HIP C-K | 8,818 |
| MIL | MI-10/MI-10K Harke | 36,600 |
| MIL | Mil Mi-26 | 44,092 |
| MIL | Mil Mi-38 | 15,432 |
| MIL | Mil Mi-171A2 | 11,023 |
| Sikorsky | S-64E/F Sky Crane | 20,000 |
| Sikorsky | S-70/UH-60 Black Hawk/SH-60 Seahawk | 9,000 |
| Sikorsky | S-76 | 8,000 |
| Kamov | Ka-226 | 2,425 |
| Kamov | Ka-32A11BC | 11,023 |
| Kamov | Ka-62 | 5,511 |
Utility helicopter operators perform a wide variety of external load work that varies region to region and season to season. Some of the most common external load operations include:
Improperly rigged cargo loads can threaten the aircraft as well as people on the ground. External loads must be prepared and inspected by trained personnel, and all rigging equipment must be rated for the weight of the load and in servicable condition.
The task of hooking sling loads up to a helicopter also presents certain dangers. In flight, a helicopter generates and stores a charge of static electricity. When the helicopter lands, this charge passes to the ground through the helicopter grounding system. However, in flight, this charge remains stored in the helicopter until a path is provided to ground. Personnel connecting a sling load must discharge this static electricity prior to any hook up. Rotorwash can also pose a hazard, causing difficulty to nearby personnel walking or standing, as well as blowing unsecured items around. Wear of safety glasses is necessary. [13]
3 days of the US Army Air Assault course is dedicated to training and testing servicemembers on the inspection of sling loads and procedures for hook-up operations. This testing is the most difficult portion of the 10 day course. [14]
The Boeing CH-47 Chinook is a tandem-rotor helicopter originally developed by American rotorcraft company Vertol and now manufactured by Boeing Defense, Space & Security. The Chinook is a heavy-lift helicopter that is among the heaviest lifting Western helicopters. Its name, Chinook, is from the Native American Chinook people of Oregon and Washington state.
The Bell 212 is a two-blade, twin-engine, medium helicopter that first flew in 1968. Originally manufactured by Bell Helicopter in Fort Worth, Texas, United States, production was moved to Mirabel, Quebec, Canada in 1988, along with all Bell commercial helicopter production after that plant opened in 1986.
The Sikorsky H-19 Chickasaw is a multi-purpose piston-engined helicopter that was used by the United States Army and United States Air Force. It was also license-built by Westland Aircraft as the Westland Whirlwind in the United Kingdom. United States Navy and United States Coast Guard models were designated HO4S, while those of the U.S. Marine Corps were designated HRS. In 1962, the U.S. Navy, U.S. Coast Guard and U.S. Marine Corps versions were all redesignated as H-19s like their U.S. Army and U.S. Air Force counterparts.
The Piasecki H-21 Workhorse/Shawnee is an American helicopter, the fourth of a line of tandem rotor helicopters designed and built by Piasecki Helicopter. Commonly called "the flying banana", it was a multi-mission helicopter, capable of being fitted with wheels, skis or floats.
The Bell 47 is a single-rotor single-engine light helicopter manufactured by Bell Helicopter. It was based on the third Bell 30 prototype, which was the company's first helicopter designed by Arthur M. Young. The 47 became the first helicopter certified for civilian use on 8 March 1946. The first civilian delivery was made on 31 December 1946 to Helicopter Air Transport. More than 5,600 Bell 47s were produced, including those under license by Agusta in Italy, Kawasaki Heavy Industries in Japan, and Westland Aircraft in the United Kingdom. The Bell 47J Ranger is a modified version with a fully enclosed cabin and tail boom.
The Sikorsky H-34 is an American piston-engined military utility helicopter originally designed by Sikorsky as an anti-submarine warfare (ASW) aircraft for the United States Navy. A development of the smaller Sikorsky H-19 Chickasaw (S-55), the H-34 was originally powered by a radial engine, but was later adapted to turbine power by the British licensee as the Westland Wessex and by Sikorsky as the S-58T. The H-34 was also produced under license in France by Sud Aviation.
The Sikorsky S-70 is an American medium transport/utility helicopter family manufactured by Sikorsky Aircraft. It was developed for the United States Army in the 1970s, winning a competition to be designated the UH-60 Black Hawk and spawning a large family in U.S. military service. New and improved versions of the UH-60 have been developed since. Civilian versions, and some military versions, are produced under various S-70 model designations.
The Bell 429 GlobalRanger is a light, twin-engine helicopter developed by Bell Helicopter and Korea Aerospace Industries. The first flight of the prototype took place on February 27, 2007, and the aircraft received type certification on July 1, 2009. The Bell 429 is capable of single-pilot IFR and Runway Category A operations.
A military transport aircraft, military cargo aircraft or airlifter is a military-owned transport aircraft used to support military operations by airlifting troops and military equipment. Transport aircraft are crucial to maintaining supply lines to forward bases that are difficult to reach by ground or waterborne access, and can be used for both strategic and tactical missions. They are also often used for civilian emergency relief missions by transporting humanitarian aid.
The Bell 214 is a medium-lift helicopter derived from Bell Helicopter's ubiquitous UH-1 Huey series. The Bell 214ST shares the same model number, but is a larger, much-modified twin-engine derivative.
The Airbus Helicopters H130 is a single engine light utility helicopter developed from the earlier Eurocopter AS350 Écureuil, one of the primary changes from which was the adoption of a Fenestron anti-torque device in place of a conventional tail rotor. It was launched and produced by the Eurocopter Group, which would later be rebranded as Airbus Helicopters.
The Schweizer 330 and S333 are turbine-powered developments of the Schweizer 300 light piston-powered helicopter. As of 2007, only the Schweizer 333 remains in production. In February 2009, the 333 was rebranded as the Sikorsky S-333. In 2018 the Schweizer R.S.G. bought the Schweizer Aircraft from Sikorsky Aircraft and it was rebranded as Schweizer S333 again.
The Kaman K-MAX is a helicopter with intermeshing rotors (synchropter) designed and produced by the American manufacturer Kaman Aircraft.
The Beechcraft Super King Air family is part of a line of twin-turboprop aircraft produced by Beechcraft. The Model 200 and Model 300 series were originally marketed as the "Super King Air" family; the "Super" designation was dropped in 1996. They form the King Air line together with the King Air Model 90 and 100 series.
An aerial crane or flying crane is a helicopter used to lift heavy or awkward loads. As aerial cranes, helicopters carry loads connected to long cables or slings in order to place heavy equipment when other methods are not available or economically feasible, or when the job must be accomplished in remote or inaccessible areas, such as the tops of tall buildings or the top of a hill or mountain, far from the nearest road. Helicopters were first used as aerial cranes in the 1950s, but it was not until the 1960s that their popularity in construction and other industries began to catch on. The most consistent use of helicopters as aerial cranes is in the logging industry to lift large trees out of rugged terrain where vehicles are not able to reach, or where environmental concerns prohibit roadbuilding. These operations are referred to as longline because of the long, single sling line used to carry the load.
The Sikorsky S-61R is a twin-engine helicopter used in transport or search and rescue roles. A developed version of the S-61/SH-3 Sea King, the S-61R was also built under license by Agusta as the AS-61R. The S-61R served in the United States Air Force as the CH-3C/E Sea King and the HH-3E Jolly Green Giant, and with the United States Coast Guard as the HH-3F, nicknamed "Pelican". This article covers several different variants of this type in different roles, one major difference compared to the S-61 was a rear ramp.
The Sikorsky S-60 helicopter, a prototype "flying crane", was derived from the S-56 in 1958. Proving to be underpowered, the development of the S-60 led to the larger, turbine-engined Sikorsky CH-54 Tarhe military transport helicopter, and its civil S-64 Skycrane variant, which were already on the drawing board by the time the sole example of the S-60 crashed on 3 April 1961.
Helitack crews are teams of wildland firefighters who are transported by helicopter to wildfires. Helicopters provide rapid transport, enabling helitack crews to quickly respond and assess a wildfire situation. Helitack crews may land near a wildfire or, if equipped and trained, rappel from a hovering helicopter. Once on the ground, crews build firelines using hand tools, chainsaws, and other firefighting tools. They often remain overnight in remote locations. After they have completed their assignment, crew members may pack up to 120 pounds of equipment over difficult terrain to reach a pick-up point. Rappellers often prepare helispots that provide better access to a fire. Helicopter crew members may also perform other duties such as tree falling, firing operations, and managing helibases.
The Robinson R66 is a helicopter designed and built by Robinson Helicopter Company. It has five seats, a separate cargo compartment and is powered by a Rolls-Royce RR300 turboshaft engine. The R66 is slightly faster and smoother than the piston-powered Robinson R44 from which it is derived. The R66 received both type and production certificates from the U.S. Federal Aviation Administration (FAA) on October 25, 2010. The R66 is a larger and turbine powered derivative of the Robinson R22 and R44 family of helicopters.
The helicopter flight rescue system (HFRS) is a helicopter insertion and extraction tool that utilizes a longline and personnel carrying device system (PCDS) to carry human loads below a helicopter in flight. These systems are often referred to as "long line", "short haul", Class D fixed line (CDFL), and other terms, and is similar to other helicopter long line systems in use throughout the world. By extending a rescuer below the aircraft and allowing the aircraft to remain clear of obstacles while a rescue is performed, a pilot can insert or extract rescuers and subjects in most types of terrain.
Media related to Helicopter hooks at Wikimedia Commons