go

Chinese weiqi or wei-ch'i Korean baduk

Game that involves two players alternately placing black and white stones on a board checkered by 19 vertical lines and 19 horizontal lines. The players attempt to conquer territory by surrounding vacant areas or capture stones by surrounding them. Points are awarded by conquering and capturing and reduced by losing one's stones. The game is also played in electronic formats. Go probably originated in China, possibly as early as circa 2300 BC. It was brought to Japan circa AD 500, where it developed into the modern game. Most identified with Japan, is also popular in China and Korea and is played worldwide.

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Chinese taijiquan or t'ai-chi-ch'üan

Ancient Chinese form of exercise or of attack and defense. As exercise, it is designed to provide relaxation in the process of body conditioning, which it accomplishes partly by harmonizing the principles of yin-yang. It employs flowing, deliberate movements with carefully prescribed stances and positions. As a mode of attack and defense, it resembles kung fu and is properly considered a martial art. Dating to the 3rd century AD, Tai Chi Chuan consists of two major schools, the Wu and the Yang. Depending on the school, the number of exercises varies from 24 to more than 100.

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or ch'i-lin

In Chinese mythology, a kind of unicorn whose rare appearance often coincides with the imminent birth or death of a sage or illustrious ruler. Appearances could also indicate the benevolence of living emperors. A qilin has a single horn on its forehead, a yellow belly, a multicoloured back, a horse's hooves, a deer's body, and an ox's tail. Legend has it that a qilin appeared to the pregnant mother of Confucius.

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or ch'i

In Chinese philosophy, the ethereal substance of which everything is composed. Early Daoist philosophers and alchemists regarded it as a vital force associated with breath and bodily fluids and sought to control its movement within the body in order to achieve longevity and spiritual power. Manipulation of qi is central to Chinese meditation, medicine, and martial arts. In the 10th–13th centuries Neo-Confucianism regarded qi as emanating from the Great Ultimate by way of li, the ordering principle of the universe, transformed into the elements through yin and yang (see yin-yang).

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or Tung Ch'i-ch'ang

(born 1555, Huating, Kiangsu province, China—died 1636) Chinese painter, calligrapher, and theoretician of the late Ming period. He is noted especially for his writings on Chinese painting, which he divided into the Northern school, which taught the acquisition of truth, and the Southern school, which emphasized sudden, intuitive understanding. At the centre of the scholarly ideal of the Southern school was the art of calligraphy, which expressed the true nature of the artist without the interposition of pictorial description. Dong Qichang's own paintings stress stark forms, seemingly anomalous spatial renderings, and naive handling of ink and brush. His ideas continue to influence Chinese aesthetic theory.

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or Kuan Han-ch'ing

(born 1241?, Dadu, China—died 1320?, China) Chinese dramatist. He belonged to a writers' guild that provided plays for performing groups. His plays often dealt with everyday events and sympathetically portrayed women of low social standing. He wrote over 60 plays, 14 of which survive, including Injustice to Dou E, Butterfly Dream, and Saving a Prostitute. Guan is often considered the greatest playwright of the Chinese classical theatre.

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or Chiang Ch'ing orig. Li Jinhai

(born 1914?, Zhucheng, Shandong, China—died May 14, 1991, Beijing) Third wife of Mao Zedong and member of the radical Gang of Four. Jiang married Mao in the 1930s but entered politics only in the 1960s. As first deputy head of the Cultural Revolution, Jiang acquired far-reaching powers over China's cultural life and oversaw the total suppression of a wide variety of traditional cultural activities. Arrested after Mao's death and accused of fomenting the widespread civil unrest that characterized the Cultural Revolution, she refused to confess guilt and received a suspended death sentence that was commuted to life imprisonment. Her death was reported as a suicide.

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or Ch'ien-lung emperor orig. Hongli

(born Sept. 25, 1711, China—died Feb. 7, 1799, Beijing) Fourth emperor of the Qing dynasty in China. His reign (1735–96) was one of the longest in Chinese history. China's boundaries reached their greatest extent, encompassing Mongolia, Tibet, Nepal, Taiwan, and portions of Central Asia. Qianlong sponsored a compilation of the Confucian Classics (see Five Classics); the compilation's descriptive catalog is still used today. At the same time, he ordered that all books containing anti-Manchu sentiments be expurgated or destroyed; some 2,600 h1s were lost. He enjoyed excellent personal relationships with Jesuit missionaries in Beijing, though Roman Catholic preaching remained officially forbidden. In the first half of his reign, agriculture made great strides and was superior to that in much of Europe. Taxes were light and education was widespread, even among the peasantry. Subsequently, military expeditions and increasing governmental corruption permanently harmed the dynasty, sowing the seeds for its decline in the 19th century. Seealso Heshen; Kangxi emperor; Manchu.

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The Boeing CH-46 Sea Knight is a medium-lift tandem rotor cargo helicopter, used by the United States Marine Corps (USMC) to provide all-weather, day-or-night assault transport of combat troops, supplies and equipment. Assault Support is its primary function, and the movement of supplies and equipment is secondary. Additional tasks include combat support, search and rescue, support for forward refueling and rearming points, CASEVAC and Tactical Recovery of Aircraft and Personnel (TRAP). The commercial version is the BV 107-II, commonly referred to as simply the "Vertol".

Development

Piasecki was a pioneering developer of tandem-rotor helicopters, with the most famous previous helicopter being the H-21 "Flying Banana". Piasecki's former company Vertol began work on a new tandem rotor helicopter designated the Vertol Model 107 or V-107 in 1957. The V-107 had two Lycoming T53 turboshaft engines, producing 860 shp (640 kW) each. The first flight of the V-107 took place on April 22, 1958. The V-107 was then put through a flight demonstration tour in the US and overseas. In June 1958, the US Army awarded a contract to Vertol for ten production aircraft designated "YHC-1A".

The order was later decreased to three, so the Army could divert funds to the V-114, also a turbine powered tandem, but larger than the V-107. The Army's three YHC-1As were powered by GE-T-58 engines. The YHC-1As first flew in August 1959, and were followed by an improved commercial/export model, the 107-II. During 1960, the U.S. Marine Corps (USMC) evolved a requirement for a twin-turbine troop/cargo assault helicopter to replace the piston engine types then in use. Following a design competition, Boeing Vertol was selected to build its model 107M as the HRB-1, early in 1961. Boeing had acquired Vertol in 1960 and renamed the group Boeing Vertol.

The helicopter was first procured in 1961 to meet the medium-lift requirements of the Marine Corps. Its first flight in August 1962 was followed by a change in designation to CH-46A. Fleet introduction of CH-46As with the Marines and the Navy's UH-46As in November 1964. The UH-46A variant was modified for use in the vertical replenishment role. The CH-46A was equipped with a pair of T58-GE8-8B turboshaft engines rated at 1,250 shp (930 kW) each and could carry 17 passengers or 4,000 pounds (1,815 kg) of cargo. The USMC received 160 CH-46As and the US Navy acquired 24 UH-46As.

Production of the improved CH-46D followed with deliveries beginning in 1966. Its improvements included modified rotor blades and more powerful T58-GE-10 turboshaft engines rated at each. The increased power allowed the D-model to carry 25 troop or of cargo. A total of 266 CH-46Ds were produced. Also, approximately 12 CH-46As were upgraded to CH-46Ds. The Navy received 10 UH-46Ds for ship resupply.

The Marines also received 174 CH-46Fs from 1968 to 1971. The F-model retained the D-model's T58-GE-10 engines but revised the avionics and included other modifications. The CH-46F was the final production model with the last helicopter being the 524th H-46 produced. The Sea Knight has undergone upgrades and modifications. Most USMC Sea Knights were upgraded to CH-46E standard. The CH-46E features fiberglass rotor blades, airframe reinforcement, and further uprated T58-GE-16 engines producing each. Some CH-46Es have been given doubled fuel capacity. The Dynamic Component Upgrade (DCU) incorporated starting in the mid-1990s provides for increased capabilities through strengthened drive systems and rotor controls.

The commercial variant, the BV 107-II, was first ordered by New York Airways in 1960. They took delivery of their first three aircraft, configured for 25 passengers, in July 1962.

In 1965, Boeing Vertol sold the manufacturing rights of the 107 to Kawasaki Heavy Industries. Under this arrangement, all Model 107 civilian and military aircraft built in Japan are known as KV 107.

On December 15, 2006, Columbia Helicopters, Inc acquired the type certificate for the Boeing Vertol 107-II, and is in the process of acquiring a Production Certificate from the FAA. Plans for actual production of the aircraft have not been announced.

Design

The CH-46 has tandem contrarotating rotors that were powered by two GE T58 turboshaft engines. The engines are mounted on each side of the rear rotor pedestal with a driveshaft to the forward rotor. The engines are coupled so either could power both rotors in an emergency. The rotors feature three blades and could be folded for on-ship operations.

The CH-46 has a cargo bay with a rear loading ramp that could be removed or left open in flight for extended cargo or for parachute drops. A belly sling hook could be attached for carrying external cargo. It has a crew of three. A pintle-mounted 0.50 in (12.7 mm) Browning machine gun was mounted on each side of the helicopter for self-defense. Service in southeast Asia resulted in the addition of armor with the guns.

The CH-46 has fixed tricycle landing gear, with twin wheels on all three units. The gear configuration causes a nose-up stance to facilitate cargo loading and unloading. The main gear are fitted in rear sponsons that also contained fuel tanks with a total capacity of 350 US gallons (1,438 L).

Operational history

Military

Known colloquially as the "Phrog", and used in all Marine combat and peacetime environments since its introduction. Still regularly flown by the Marine Corps, its longevity as a reliable airframe has led to such mantras as "phrogs phorever" and "never trust a helicopter under 30".

CH-46E Sea Knights were used by the USMC during its 2003 invasion of Iraq. CH-46Es transported personnel, brought supplies to forward arming and refueling points (FARP), carried ammunition and various tasks. Marine CH-46Es and CH-53Es carried US Army Rangers and Special Operations troops in a mission to rescue captured Army Private Jessica Lynch on 1 April 2003.

While the United States Navy retired the airframe on September 24, 2004, replacing it with the MH-60S Knighthawk, the Marine Corps plans to maintain its fleet until the MV-22 is fully fielded. In March 2006 Marine Medium Helicopter Squadron 263 (HMM-263) was deactivated and redesignated VMM-263 to serve as the first MV-22 squadron. The replacement process is expected to continue through the other medium helicopter squadrons into 2014.

Civilian

The Civilian version, the BV 107-II Vertol was developed prior to the military CH-46, and was operated commercially by New York Airways, Pan American World Airways and currently solely by Columbia Helicopters. As of December 15, 2006 Columbia Helicopters has purchased the Type certificate of the Model 107 from Boeing. Currently the company is seeking FAA issuance of a Production Certificate to produce parts with eventual issuance of a PC to produce aircraft.

Variants

US versions

Total U.S. H-46 production amounted to 524, ending in 1971.Model 107 : Company model number.Model 107-II : The third YHC-1 prototype was converted into a commercial airline helicopter. All subsequent commercial aircraft were produced as BV 107-II.Model 107M : Military transport prototype for the United States Marine Corps.YHC-1A : Three Model 107s for test and evaluation by the United States Army. Adopted by the United States Marine Corps as the HRB-1. Later redesignated YCH-46C. Three built.YHC-1B : Were not Model 107s but five Model 114s that later became the CH-47A ChinookHRB-1 : Original designation before being renamed as CH-46A before delivery under the 1962 United States Tri-Service aircraft designation systemCH-46A : Assault, utility medium transport and SAR helicopter for the USMC, fitted with two 935-kW (1,250-shp) General Electric T58-GE-8 turboshaft engines. (Previously HRB-1). 164 built.UH-46A : Utility medium transport helicopter for the United States Navy. Similar to the CH-46A. 14 built.HH-46A : A small number of HH-46As were converted into SAR helicopters for the United States Navy base rescue role.RH-46A : A small number of CH-46As were converted into minesweeping helicopters for the US Navy.UH-46B : Development of the CH-46A to specification HX/H2 for the United States Air Force; cancelledYCH-46C :YHC-1A redesignated in 1962.CH-46D : Assault and utility medium transport helicopter for the USMC, fitted with two 1044-kW (1,400-shp) General Electric T58-GE-10 turboshaft engines. 266 built.HH-46D : A small number of UH-46Ds were converted into SAR helicopters.UH-46D : Utility transport helicopter for the US Navy combat supply role. Similar to the CH-46D. 10 built and one conversion from CH-46D.CH-46E : Approximately 350 -D and -F airframes were updated to CH-46E standards with improved avionics, hydraulics, drive train and upgraded T58-GE-16 engines.HH-46E : A small number of CH-46Es were converted into SAR helicopters.CH-46F : Improved version of CH-46D, electrical distribution, com/nav update BUNO 154845-157726. Last production model in the United States. 186 builtVH-46F : VIP transport helicopter.CH-46X : Also known as the Boeing Model 360, this Advance Technology Demonstrator from the 1980s never entered production. The aircraft relied heavily on composites for its construction and had a beefier drive train to handle the twin Avco-Lycoming AL5512 engines (4200shp).

Canadian versions

CH-113 Labrador : Search and rescue version of the Model 107-II-9 for the Canadian Forces Air Command. 18 built.CH-113A Voyageur : Assault and utility transport version of the Model 107-II-9 for the Canadian Forces. 12 built.

Swedish Versions

Hkp 4A : Boeing Vertol 107-II, used originally by Air Force for SAR. (10), Hkp 4B : Boeing Vertol 107-II-15, Navy (3)HKP 4C : Kawasaki KV-107-II-16, Navy (8)HKP 4D : Rebuilt Hkp 4A for SAR/ASW (Navy) (4)

Japanese versions

KV-107II-1 (CT58-110-1)

Utility transport version.KV-107II-2 (CT58-110-1)

Commercial airline version.KV-107IIA-2 (CT58-140-1)

Improved version of the KV-107/II-2.KV-107II-3 (CT58-110-1)

Minesweeping version for the JMSDF, 3 built.KV-107II-3A (CT58-IHI-10-M1)

Uprated version of the KV-107/II-3.KV-107II-4 (CT58-IHI-110-1)

Assault and utility transport version for the JGSDF.KV-107II-4A (CT58-IHI-140-1)

Uprated version of the KV-107/II-4.KV-107II-5 (CT58-IHI-110-1)

Long-range SAR version for the JASDF.KV-107II-5A (CT58-IHI-104-1)

Uprated version of the KV-107II-5A.KV-107II-7 (CT58-110-1)

VIP transport version.KV-107II-16

HKP 4C for Swedish Navy. Powered by Rolls-Royce Gnome H.1200 turboshaft engines.KV-107IIA-17 (CT58-140-1)

Long-range transport version for the Tokyo Metropolitan Police Department, 1 built.KV-107IIA-SM-1 (CT58-IHI-140-1M1)

Firefighting helicopter for Saudi Arabia.KV-107IIA-SM-2 (CT58-IHI-140-1M1)

Aeromedical and rescue helicopter for Saudi Arabia.KV-107IIA-SM-3 (CT58-IHI-140-1M1)

VIP transport helicopter for Saudi Arabia.KV-107IIA-SM-4 (CT58-IHI-140-1M1)

Air ambulance helicopter for Saudi Arabia.

Operators

Military Operators

• Japan Air Self Defence Force
• Japan Ground Self Defence Force
• Japan Maritime Self Defence Force
• Royal Saudi Air Force
• Swedish Air Force
• Swedish Navy
• United States Navy
• United States Marine Corps

Civilian Operators

• Helifor Canada Corp (under lease from Columbia Helicopters)
• Columbia Helicopters

Former Operators

• Canadian Forces Air Command
• Canadian Coast Guard
• Kawasaki Helicopter System, LTD
• Tokyo Metropolitan Police Department
• Royal Thai Army
• New York Airways
• Pan Am

Specifications (CH-46)

See also

References

• CH-46E Sea Knight Helicopter. HQMC Fact File. U.S. Marine Corps. .

External links

• CH-46D/E Sea Knight and CH-46 history pages on U.S. Navy site; CH-46 page on USMC site
• CH-46 product page and CH-46 history page on Boeing.com
• Columbia Helicopters - Largest Civilian Operator of BV/KV Model 107
• Boeing Vertol 107 & H-46 Sea Knight on Airliners.net
• Kawasaki Vertol 107 on Airliners.net
• Kawasaki Helicopter Services (S.A.) Ltd.