Given the question: Information:  - TurboJET is the brand name for the operations of the Hong Kong-headquartered Shun Tak-China Travel Ship Management Limited, which was established from the joint venture between Shun Tak Holdings Limited and China Travel International Investment Hong Kong Limited in July 1999. It operates hydrofoil ferry services in southern China.  - Aviation is the practical aspect or art of aeronautics, being the design, development, production, operation and use of aircraft, especially heavier than air aircraft. The word "aviation" was coined by French writer and former naval officer Gabriel La Landelle in 1863, from the verb "avier" (synonymous flying), itself derived from the Latin word "avis" ("bird") and the suffix "-ation".  - An afterburner (or a reheat) is a component present on some jet engines, mostly those used on military supersonic aircraft. Its purpose is to provide an increase in thrust, usually for supersonic flight, takeoff and for combat situations. Afterburning is achieved by injecting additional fuel into the jet pipe downstream of (i.e. "after") the turbine. The advantage of afterburning is significantly increased thrust; the disadvantage is its very high fuel consumption and inefficiency, though this is often regarded as acceptable for the short periods during which it is usually used.  - A ducted fan is a propulsion arrangement whereby a mechanical fan, which is a type of propeller, is mounted within a cylindrical shroud or duct. The duct reduces losses in thrust from the tips of the props, and varying the cross-section of the duct allows the designer to advantageously affect the velocity and pressure of the airflow according to Bernoulli's Principle. Ducted fan propulsion is used in aircraft, airships, airboats, hovercraft and fan packs.  - An airliner is a type of aircraft for transporting passengers and air cargo. Such aircraft are most often operated by airlines. Although the definition of an airliner can vary from country to country, an airliner is typically defined as an aircraft intended for carrying multiple passengers or cargo in commercial service.  - A jet aircraft (or simply jet) is an aircraft (nearly always a fixed-wing aircraft) propelled by jet engines (jet propulsion).  - McDonnell Douglas was a major American aerospace manufacturing corporation and defense contractor formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own merger with Boeing in 1997, it produced a number of well-known commercial and military aircraft such as the DC-10 airliner and F-15 Eagle air-superiority fighter.  - A jet engine is a reaction engine discharging a fast-moving jet that generates thrust by jet propulsion. This broad definition includes airbreathing jet engine(turbojets, turbofans, ramjets, and pulse jets) and non-airbreathing jet engines (such as rocket engines). In general, jet engines are combustion engines.  - A jet airliner (or "jetliner", or "jet") is an airliner powered by jet engines (passenger jet aircraft). Airliners usually have two or four jet engines; three-engined designs were popular in the 1970s but are less common today.  - The McDonnell Aircraft Corporation was an American aerospace manufacturer based in St. Louis, Missouri. The company was founded on July 6, 1939 by James Smith McDonnell, and was best known for its military fighters, including the F-4 Phantom II, and manned spacecraft including the Mercury capsule and Gemini capsule. McDonnell Aircraft later merged with the Douglas Aircraft Company to form McDonnell Douglas in 1967.  - A portmanteau (; plural "portmanteaus" or "portmanteaux" ) or portmanteau word is a linguistic blend of words, in which parts of multiple words or their phones (sounds) are combined into a new word.  as in "smog", coined by blending "smoke" and "fog", or "popportunity", from "popping" and "opportunity", or "motel", from "motor" and "hotel". In linguistics, a portmanteau is defined as a single morph that represents two or more morphemes.  - The Boeing 717 is a twin - engine , single - aisle jet airliner , developed for the 100 - seat market . The airliner was designed and originally marketed by McDonnell Douglas as the MD - 95 , a derivative of the DC - 9 family . Capable of seating up to 134 passengers , the 717 has a design range of 2,060 nautical miles ( 3,815 km ) . It is powered by two Rolls - Royce BR715 turbofan engines mounted at the rear of the fuselage . The first order was placed in October 1995 by ValuJet Airlines ( later AirTran Airways ) ; McDonnell Douglas and Boeing merged in 1997 prior to production . The airliner entered service in 1999 as the Boeing 717 . Production ceased in May 2006 after 156 were built .  - The normal definition for the bypass ratio (BPR) of a turbofan engine is the ratio between the mass flow rate of the bypass stream to the mass flow rate entering the core. A 10:1 bypass ratio, for example, means that 10 kg of air passes through the bypass duct for every 1 kg of air passing through the core. Note that in an aft fan engine, like the General Electric CJ805-23, all of the fan air enters the bypass stream, whereas on most turbofans only the air entering the outer section of the fan passes to the bypass duct. Another special case is the General Electric TF39 where most of the fan air plus some of the low pressure compressor air enter the bypass duct.  - The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the "turbo" portion refers to a gas turbine engine which achieves mechanical energy from combustion, and the "fan", a ducted fan that uses the mechanical energy from the gas turbine to accelerate air rearwards. Thus, whereas all the air taken in by a turbojet passes through the turbine (through the combustion chamber), in a turbofan some of that air bypasses the turbine. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of those contributing to the thrust. The ratio of the mass-flow of air bypassing the engine core compared to the mass-flow of air passing through the core is referred to as the bypass ratio. The engine produces thrust through a combination of these two portions working in concert; engines that use more jet thrust relative to fan thrust are known as "low-bypass turbofans", conversely those that have considerably more fan thrust than jet thrust are known as "high-bypass". Most commercial aviation jet engines in use today are of the high-bypass type, and most modern military fighter engines are low-bypass. Afterburners are not used on high-bypass turbofan engines but may be used on either low-bypass turbofan or turbojet engines.    What entity does 'boeing 717' has the relation 'use' with?
The answer is:
commercial aviation