the ch-46 "SeaKnight" transport helicopter first flew in 1958, and officially served in the U.S. navy in 196. It served as a material transport personnel and other tasks. Although it is not a special combat aircraft, it often performs some special operations.
The ch-46 helicopter is one of the most important combat attack helicopters of the U.S. Marine Corps, and its shape is a little bit. The US Navy uses this helicopter to transport equipment to ships or perform search and rescue missions.
the ch-46 helicopter was made by Boeing company of the United States and entered service in 1964.
During the Vietnam War, this kind of helicopter played a great role. CH-46 first served during the Vietnam War. At first, it was used to transport troops and goods from naval vessels to land, or from land to ships. In addition, it carried out thousands of missions to rescue injured marines. Since the Vietnam War, CH-46 has participated in almost all major US military operations, including the Afghanistan war in 21 and the ongoing war against Iraq.
1. Mission
The mission of CH-46 transport helicopter is to quickly transport combat troops, support equipment and supplies from amphibious assault landing ships and built airports to forward bases. These bases are simple and have limited maintenance and logistics support capabilities. The navy also uses CH-46D helicopter to carry out tasks such as vertical replenishment, internal logistics of battle groups, medical evacuation and search and rescue.
II. Data
Main contractor: Boeing Vito Company
Crew members: 4
Time of initial combat capability: 1964
Number of aircraft owned: 324
Captain: 13.7 meters
Rotor diameter: 15.31 meters
Takeoff weight: 1,1.
battery life: 2 hours (CH-46D)
1.75 hours (CH-46E)
Weapons: 2 MZ(25.4 mm) or M6(7 mm) machine guns (equipped with CH-46E aircraft only)
III. Application
1 of the US Marine Corps. Our 12 CH-46E transport helicopters and 42 CH/HH-46D transport helicopters from 21 transport units of the Navy (with two types of transport aircraft) carried out the task of supporting the operations of "Desert Shield" and "Desert Storm". These helicopters are used to transport marines, sailors, cargo, mail, ammunition, medical evacuation, search and rescue, etc.
Design features
Rotor system
Two pairs of three-blade tandem counter-rotating rotors are paid to the blades of Boeing 17 II of New York Airlines and Kawasaki Heavy Industries Co., Ltd., which adopt a mouth-shaped steel beam, a box-shaped structure with bonded aluminum-ribbed FRP (carved aluminum) skin, and a stainless steel strip at the rear edge. Blade overhaul life force of 5 hours. The hub is equipped with a shimmy damper. The renovation life of propeller is 2 hours. Rotor revolutions: the speed is 264 revolutions per minute. CH/UH-46 system for praying when the paddle is powered, which includes: a set of indicator lights to indicate the angle of attack of the paddle before folding; A hydraulic motor connected with the rear transmission system is used to rotate the rotor to the proper azimuth and then lock the rotor; A set of motors installed in folding hinges, whose reducers can fold the blades with a reduction ratio of 16,: 1. The folding system is used for bearings without lubrication, and the folding time is about 6 seconds. The system has undergone 5 folding tests on the test bench, and no damage accident has occurred.
transmission system
the power of each engine is input to the reducer through the clutch, and the front and rear reducers are respectively driven and the two rotors are driven. The rotor speed ratio of the engine is 73.722: 1 for CH-46A and 73.77: 1 for CH-113.
Power plant
Type p>17 II: Two 932kW (1267 shaft horsepower) CT-58-11-1 turboshaft engines of General Electric Company are installed side by side at the base of the rear rotor tower; HRp。 Type 4 is equipped with two 932-watt (1,267-shaft horsepower) "Nome" H.12 turboshaft engines from Bristol Sidley Company. 17 "A" modified and updated: CT58-14 turboshaft engine with 44 kW (1419 shaft horsepower). CH-46A is equipped with two 932 dry watts (1 267 shaft horsepower). T58-GE-8B of General Electric Company is a turboshaft engine. The CH/UH-46D is equipped with two 144 kW (1419 HP) turboshaft engines.
two self-sealing fuel tanks, Type p>17II and Type 17 IIA, are located in buoys on both sides of the fuselage. The fuel tanks are made of crash-resistant materials, with a total capacity of 325 liters. The total capacity of CH-46/UH-46 fuel tank is 438 liters, and the fuel filler is at the upper part of the fuel tank. The total oil quantity is 15.9 liters.
Machine body
Semi-hard shell structure with rectangular cross section, mainly made of high-strength aluminum alloy with and without aluminum cladding. Transverse diaphragm and reinforcing frame are the bearing parts of transmission system, engine and landing gear. The lower surface of the rear fuselage, which is inclined upward, is composed of the rear springboard on multi-purpose and military models. The loading and unloading springboard was replaced by the luggage compartment at the back of the fuselage of the passenger plane. The fuselage is sealed, which can take off and land on the water, and even work under the condition of medium wave height; The floating system consists of nine sealed compartments, and the buoyancy and stability of the helicopter can still be maintained after any sealed compartment < P > fails.
landing gear
non-retractable front three-point landing gear. Each landing gear has two tubeless wheels with a size of 8X5．5 and a tire pressure of 1.35X1 Pa (1.55kg/cm), and adopts a disc brake mechanism. Landing gear oil. There are two damping holes in the air damping strut. When the compression speed is less than .35m/s, the larger damping hole is blocked by the spring and the mushroom valve, and the oil passes through the small damping hole, thus ensuring that the helicopter has good ground vibration characteristics; when the compression speed is greater than .35m/s, the valve is opened, ensuring that the strut has good vibration reduction effect.
Cockpit
Type p>17 II: The standard cockpit layout consists of two pilots, one flight attendant and 25 passengers. Cockpit * * * has 8 rows of seats, with 2 pairs of seats in each row on the left, single seat in the right, and 4 seats in the last row with an aisle in the middle. There is a luggage rack in the cabin and a luggage compartment with rollers which can hold 68 kilograms of goods at the lower part of the rear fuselage. The rear springboard can be powered on the ground or in the air. When loading extra-long goods, the rear springboard can be removed or completely opened. Ch/uh-46: 3 crew members; 25 soldiers
and 1 commander. There is an up-and-down split kneeling door in front of the loading cabin cloth. The upper half of the hatch is received by the upper part of the fuselage through the slide rail. The lower half is hinged at the bottom of the fuselage and opens outwards, with a boarding ladder attached inside. The loading springboard and the rear fuselage door can be opened in flight or on water. The bearing capacity of the central part of the floor is 14. 36 dry cattle/m' (1 464.6 kg/m'), with a row of rollers on both sides for transporting standard military freight flat or wire baskets. The outside of the floor is a driveway, which can bear 454 kg tire load. The winch system for lifting goods and personnel can be operated by one person. It has a variable-speed winch, which can lift 97 kilograms of goods at a speed of 9 meters per minute or 272 kilograms of personnel and other articles at a speed of 3 meters per minute. There is an external hanging hook on the floor, which can hang 4535 kilograms of goods.
system
(ch/uh-46) cabin heater is combustion type. The pressure of the hydraulic system used in the flight control booster is 13X1‘' Pa (15kg/cm'), and that of other systems is 26X1' Pa (21kg/cm'). The electrical system includes two 4 KVA alternators and one 2 Amp DC generator. Solar's auxiliary power unit is installed to start the engine and check the system.
The blade
adopts a 2-volt and 2-kva electric deicing system, and six conductors are laid by flame spraying along the leading edge of the blade. The thickness and width of each conductor vary with the heating requirements of the blade in Ye Zhan direction. These conductors are periodically heated to remove ice. The deicing system is controlled by radioactive ice thickness gauge. When the thickness of the ice layer on the rotor reaches 4.77 mm, power-on deicing is started, and the three blades of each rotor are powered on at the same time to ensure that it will not cause excessive vibration. The two rotors do not deice at the same time. Electronic equipment and instrument standard instrument flight equipment. CH- 46 is equipped with multiple stability augmentation system and automatic balancing system. In the early CH- 46, the sudden stall flutter of the trailing blades occurred, which caused excessive stress on the upper control part, so it was necessary to strictly limit the allowable total weight, center of gravity range, speed and altitude of the helicopter. Therefore, a cruise indicator is installed on the helicopter, which can indicate the stress level of the control part of the rotor < P >, thus relaxing the restrictions and reducing the workload of the driver when driving.