Not a single western-made helicopter can take on as much cargo as a Chinook can take, and as such it will most likely remain in operation for several more decades to come.
The Chinook helicopter is scheduled to remain in service after its centenary, which will happen in 2060 year. Let's look at how Boeing is going to keep this workaholic at the forefront of operational capabilities.
Given the fact that the CH-47 Chinook helicopter from Boeing made its first flight at the beginning of 60-s, and the American army plans to exploit it further on 2060, it may well become the first in the world and may even be the only "century-old" helicopter .
The production of the Chinook heavy transport helicopter continues and has not stopped for more than 50 years, in aviation in this he was surpassed only by the Lockheed Martin transport aircraft C-130 Hercules. Having survived all his peers in the American army, he may well outlive many of those who came after him, because the army announced its plans to fly this heavy transport helicopter with longitudinal rotors “at least” until the 2060s, and possibly further.
At a briefing held at the Boeing plant in Philadelphia, Randy Rott, director of cargo helicopter development programs, explained the reasons for extending Chinook’s life and also outlined the company's plans to extend the life of the helicopter until its retirement day.
“Eighteen countries, including the United States, the United Kingdom, Japan, Canada, Italy, Australia, the Netherlands, Spain, Greece, South Korea, Argentina, the United Arab Emirates, Egypt, Thailand, Taiwan, Turkey, Libya and Morocco, operate today a Chinook helicopter, The world flies 900 such machines. This project and its capabilities are continuing; a large number of helicopters have been serving in these countries for quite a long time, ”he said.
The current priority program of the US Army has determined the total number of 473 helicopter Chinook. This number includes the new CH-47F models and the upgraded CH-47D (which have some components, such as rotor hubs, blades and transmissions repaired, and everything else is new). Of these, 319 machines were delivered in May 2015. The US Department of Defense is currently in the final stages of implementing its second multi-year contract on the CH-47F option, according to which 2013 helicopters must be made with 2017 to 155 (plus the 60 option, of which 25 has already been built), including machines for customers on the program of sales of military equipment abroad.
“Chinook is one of the few programs nowadays, which for almost every customer runs ahead of schedule. This is important, because a customer who wishes to receive a helicopter in the 2019 year should in no case receive it in the 2020 year, ”noted Rott.
The production line in Philadelphia is designed to produce 60 helicopters per year (the minimum economically viable volume of 36 helicopters per year); however, usually the cycle duration from issuing a contract to delivery to foreign customers is 36 months, although for the American army it can be only 24 a month, since the state issues orders for products with a long production time in advance. According to Rott, Boeing has enough orders for this time to produce the latest version of the CH-47F / MH-47G Chinook, which will run until the 2019 year.
“After 2019, we will most likely have to re-evaluate production volumes in order to understand what quantity will be at least not unprofitable, but the US army has reached a record, declaring its intention to exploit Chinook before 2060's. This is due to the fact that there is no other such aircraft that can (or plans to) provide these capabilities. ”
If the US Army plans to operate its Chinook helicopters until the 2060-s, then it must make several additional improvements over this period in order to continue to fly them. Since the flight of the first CH-47A helicopter in the 1962, the maximum gross mass of the Chinook has grown from 15000 to 23000 kg, demonstrating a decent growth in capabilities over time.
The UK is the largest operator of Chinook helicopters outside the United States.
The Chinook production line in Philadelphia will produce helicopters in the newest version of the CH-47F / MH-47G up to the 2019 year
As for the modifications of the CH-47D variant, which turn it into the CH-47F model, the most noticeable here are the glass cockpit and the DAFCS (digital automatic flight control system) digital automatic flight control system. “From an operational point of view, DAFCS has become the most significant improvement in the CH-47F, testimonials from users that we receive. This turns your ideas about what a helicopter can do - it is basically a control of sustainability. You can leave the helicopter after a hang, take a walk and it will just stand still, ”said Rott.
Another improvement to the CH-47F aircraft is to install the Cargo On and Off Loading System COOLS (Cargo On and Off Loading System) in the cargo hold, which replaced the HICHS (Helicopter Internal Cargo Handling System). The HICHS system used metal rollers on the floor to move the pallets, which meant that the helicopter was difficult to configure for other tasks. The COOLS system uses double-sided turning blocks, they are on one side flat, and on the other are rollers (a similar system is used in the Boeing C-17 Globemaster III transport aircraft). This not only allows you to easily configure the aircraft for different tasks, but also to leave under the system a ballistic defense that you had to shoot before.
System of loading and unloading cargo COOLS helicopter Chinook
The British Air Force’s Chinook helicopter demonstrates its payload by raising the Sea King’s helicopter in the North Scottish Highlands.
The Chinook helicopter on the sides installed optional fuel tanks (see photo). Although they increase the range and duration of the flight, they affect the air flow downstream along the fuselage, which may affect the available payload.
As for the short-term improvements of the CH-47F helicopter, the American army is currently in the process of compiling a variant analysis of a possible modernization of the Block 2. “It will be an evolutionary process based on what has been done before with the goal of gaining increased opportunities, without having to reinvent the wheel and more importantly, without having to pay for it again,” said Rott, adding that “none of the proposed opportunities are not associated with high-risk technologies. ”
Although the modernization of the Block 2 is still being finalized, it will most likely include the advanced blade of the main rotor ACRB (Advanced Chinook Rotor Blade). ACRB is still under development; This is not a flat blade, it differs in geometry and a new asymmetrical aerodynamic profile in order to increase the lift force by approximately 900 kg per blade (5400 kg per helicopter).
The design principles were that in order to simplify the modernization, the first 45 centimeters of the blade, where it is attached to the sleeve, should be identical to the old blade (ACRB is made of the same materials as the old blade). “ACRB is currently undergoing a stage of presentations and large-scale models, according to the schedule it will be ready for installation on machines until about the 2019 of the year,” Rott said. “The project is funded by Boeing and the US Army, and we expect it to become part of not only the new Chinook helicopters, but also the existing platforms undergoing modernization.” Although the ACRB blade is designed to simplify the upgrade process, some refinement of the helicopter flight control software will be required.
In August 2015, the US Army announced that it expects to resume production of the Chinook MH-47G for special tasks in the updated Block 2 configuration. The US Army Special Operations Command (USASOC) is currently deploying an 61 upgraded MH-47G Block 1 helicopter (62 delivered: 35 CH-47D, nine MH-47D and 18 MH-47E; one was lost in Afghanistan) and one was lost in Afghanistan) and nine and nine were lost in Afghanistan) and nine and nine were lost in Afghanistan) MH-47G.
Chinook helicopter in the version HC.6 of the British Air Force
Production of the last eight MH-47G Block 1 helicopters is currently completed, but the American Army Aviation Systems Integration Directorate proposes to resume their production in order to supply an unnamed number of new Block 2 helicopters to replace some or all of the upgraded platforms to the Block 1 configuration.
It is expected that the Block 2 retrofit machines will go into service with the American army at the start of the 2020, although this will depend on government funding and other factors. After that, the previously released Chinook Block 1 helicopters will most likely be upgraded to Block 2 configuration in order to have all the machines of the same standard.
In addition to Block 2, the company plans to carry out one or even two Block-type upgrades of the current CH-47F / MH-47G models, planned by the army, for the Chinook helicopters, or by giving them the Block 3 prefix or the symbol CH-47H. “If Block 2 starts to go off the production line at the beginning of 2020's, and you have to build 500 machines, then they will be manufactured by about 2035 year. What happens to Chinook depends on where the FVL [Future Vertical-Lift] advanced heavy transport helicopter program is at that time, but if this is the initial development phase, you can proceed to Block 3, ”said Rott .
“Of course, we are already thinking about it, but it all depends on what you want to achieve, greater speed, range, payload, size of the cargo compartment, survivability, or all at once?”
One design feature that distinguishes the Chinook from any helicopter flying today (with the exception of another Boeing-Vertol 107 model) is its configuration with a longitudinal rotor arrangement. This feature provides superior lift and speed, and will be at the core of any future Block 3 or CH-47H upgrade program.
“The longitudinal scheme became the embodiment of the idea of the designer of helicopters Frank Pyaseki. Within the relatively small area of the projection of the two rotors, you have all the traction necessary for lifting, while at the same time a tail rotor is needed for a helicopter with a traditional rotor to counteract the jet torque, Rott explained. - Along with the increase in lift, the longitudinal scheme with a high raised rear pylon of the main rotor allows trucks to immediately drive into the ramp for loading, which is impossible for traditional helicopters. The pilot is also not so worried about the strength of the wind and the inclined landing sites, in addition, the helicopter is safer for ground personnel. A Chinook helicopter can also climb large heights with a heavier load. These are amazing opportunities and it is surprising to me why the project of a helicopter with a similar scheme has not really been implemented in other countries. ”
While many modern standard helicopters have moved from main rotors with two or three blades to rotors with four or five blades to increase speed and aerodynamic lift, Chinook stopped on its configuration of two main rotors on three blades. Rott explained: "The six blades of the two rotors, given their current length and width, create excellent lifting force."
“The Chinook 347 prototype, exhibited at Fort Rucker in Alabama, was an experimental platform, it had screws with four blades plus wings. During test flights in 1965, the possibility of obtaining additional speed and lift was tested. One of the four-blade configuration problems is that you lose reliability when the blades overlap during rotation, and therefore you need to either lengthen the fuselage to prevent them from overlapping or shorten the blades. But at the same time, such a scheme can not be excluded in the future. "
According to Mr. Rott, Boeing began research to replace the Honeywell T55 twin turbine engines with a new and more powerful power plant, although this requirement has not yet been defined. “We have been thinking a lot about the new engines, but so far there is no movement in this direction. Of course, if you are going to fly up to the 2060 of the year, and you also want to install four blades, this almost accurately determines the need for a new engine, but for now we are thinking. The current engine is fantastic and exactly suitable for all the tasks performed by the helicopter today, but if you are thinking about increasing the load capacity in the future, then you need a larger engine, most likely already somewhere in 2020's. A stronger transmission and powertrain is one of the components of the Block 2 retrofit, after which we can talk about installing a more powerful engine. ”
In addition to increasing the payload of the Chinook helicopter, Boeing also considered the possibility of increasing the cross section of the main cabin to transport ever-increasing military cargo. However, as with any other refinement, it indirectly affects other characteristics of the helicopter.
“In order to include military cargo of large sizes, it was planned to increase the cross-section of the hull. But immediately there is a problem with the transportation of the Chinook helicopter in the C-17 transport aircraft, in this case it is necessary to expand its cargo compartment accordingly. Another problem is the skew air flow around the fuselage during a helicopter hover, since a wider fuselage reduces lift, ”Rott said. There is also a problem with the "plump" options Chinook. Of course, the increased fuel tanks allow you to have more fuel, but the disadvantage here is again in the skew of the air flow and the greater mass that needs to be lifted into the air. "We will offer customers increased fuel tanks only upon their request, and not as a base case."
Unloading a Chinook helicopter from a C-17 transport plane
In general, all Boeing’s thinking about possible improvements to the existing Chinook helicopter is what promising technologies may be available and how much they may cost. “We do not want to offer something that the army cannot afford, but at the same time we want the army to receive things that it can fully afford. It's all about the art of the possible, ”concluded Rott.
Remaining in service for more than 50 years, Chinook is likely to remain in service for 50 years, which will make it the world's first "centenary" helicopter
Technical characteristics of the transport Chinook helicopter
Blade diameter: 18,29 m
Length with rotating screws: 30,14 m
Fuselage length: 15,46 m
Height: 5,68 m
The width of the fuselage: 3,78 m
Maximum speed: 302 km / h
Cruise speed: 291 km / h
Range: 370 km
Service ceiling: 6000 m
Maximum total weight: 22680 kg
Payload: 10886 kg
Of all the types of helicopters in service with the American army, Chinook was least affected by recently announced restructuring plans, according to which Bell OH-58 Kiowa helicopters are being decommissioned, Boeing AH-64 Apache is being transferred from the National Guard to the current army, and part of the Sikorsky army vehicles UH-60 Black Hawk transferred to the National Guard. This means that the US Army knows exactly what it has and what it wants from its Chinook helicopters.
In addition to the United States, the Chinook helicopter was sold to 17 countries. All operators with the exception of Argentina (for financial reasons) are still operating these helicopters.
As for further potential short-term and medium-term needs for heavy transport helicopters Chinook, then experts predict a portfolio of current or new orders up to 2024 of the year could be 915 machines with a total value of 42 billion dollars.