Jet Propellant Thermally Stable (JPTS) is a jet fuel originally developed in 1956 for the Lockheed U-2 reconnaissance aircraft.
Because of tight security restrictions enforced during the U-2's development, batches of fuel that were delivered to the aircraft's engine manufacturer were initially labeled LF-1.
In 1956, a year after the U-2's first flight, a USAF Captain assigned to the Fuels Branch was instructed to buy a tank car load of LF-1 and have it shipped to an engine manufacturer. Not knowing what LF-1 was, he obtained a sample, had it analyzed, and determined that it was paraffinic kerosene, a fluid commonly known as charcoal lighter fluid (hence LF-1). [1]
Specification MIL-T-25524 was later written to include an additive for improving JPTS' thermal oxidative stability. [2]
JPTS has a flash point of 43 °C (110 °F), a freezing point of -53 °C (-64 °F) [3] and flammability limits of 1 and 6 %. It has an appearance of a water-white clear liquid with specific gravity of 0.816. It is insoluble in water. It is composed of a complex mixture of petroleum hydrocarbons. [4]
JPTS has a lower freeze point, lower viscosity, and higher thermal stability than standard aviation fuels. The fuel's low viscosity is needed to overcome the risk of it freezing in the low temperatures encountered during flight at high altitudes. JPTS also serves as coolant of engines and aerodynamically heated surfaces.
As the fuel flow to the U-2's engines at cruise altitudes is about sixteen times lower than at sea level, the dwell time over hot surfaces is longer and increases the chances of thermal breakdown; JTPS's high thermal stability is therefore desired to avoid coking and deposition of varnishes in the piping. [5]
JPTS is a specialty fuel and is produced by only two oil refineries in the United States. As such, it has limited worldwide availability and costs over three times the per-gallon price of the Air Force's primary jet fuel, JP-8. Research is under way to find a cheaper and easier alternative involving additives to generally used jet fuels. A JP-8 based alternative, JP-8+100LT, is being considered. JP-8+100 has increased thermal stability by 100 degrees F more than stock JP8, and is only 0.5 cents per gallon more expensive; low temperature additives can be blended to this stock to add the desired cold performance. [5]
The terms gasoline and petrol identify and describe the petrochemical product characterised as a transparent, yellowish, and flammable liquid, which is used as a fuel for spark-ignited, internal combustion engines. As the fuel for petrol engines, gasoline is chemically composed of organic compounds derived from the fractional distillation of petroleum, and later is chemically enhanced with gasoline additives.
Liquid hydrogen (H2(l)) is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.
The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a combination of the preceding generation engine technology of the turbojet, and a reference to the additional fan stage added. It consists of a gas turbine engine which achieves mechanical energy from combustion, and a ducted fan that uses the mechanical energy from the gas turbine to force air rearwards. Thus, whereas all the air taken in by a turbojet passes through the combustion chamber and turbines, in a turbofan some of that air bypasses these components. A turbofan thus can be thought of as a turbojet being used to drive a ducted fan, with both of these contributing to the thrust.
Avgas is an aviation fuel used in aircraft with spark-ignited internal combustion engines. Avgas is distinguished from conventional gasoline (petrol) used in motor vehicles, which is termed mogas in an aviation context. Unlike motor gasoline, which has been formulated without lead since the 1970s to allow the use of catalytic converters for pollution reduction, the most commonly used grades of avgas still contain tetraethyl lead, a toxic substance used to prevent engine knocking. There are ongoing efforts to reduce or eliminate the use of lead in aviation gasoline.
A hydraulic fluid or hydraulic liquid is the medium by which power is transferred in hydraulic machinery. Common hydraulic fluids are based on mineral oil or water. Examples of equipment that might use hydraulic fluids are excavators and backhoes, hydraulic brakes, power steering systems, automatic transmissions, garbage trucks, aircraft flight control systems, lifts, and industrial machinery.
Synthetic oil is a lubricant consisting of chemical compounds that are artificially modified or synthesised. Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be synthesized from other raw materials. The base material, however, is still overwhelmingly crude oil that is distilled and then modified physically and chemically. The actual synthesis process and composition of additives is generally a commercial trade secret and will vary among producers.
Aviation fuels are petroleum-based fuels, or petroleum and synthetic fuel blends, used to power aircraft. They have more stringent requirements than fuels used for ground use, such as heating and road transport, and contain additives to enhance or maintain properties important to fuel performance or handling. They are kerosene-based for gas turbine-powered aircraft. Piston-engined aircraft use leaded gasoline and those with diesel engines may use jet fuel (kerosene). By 2012, all aircraft operated by the U.S. Air Force had been certified to use a 50-50 blend of kerosene and synthetic fuel derived from coal or natural gas as a way of stabilizing the cost of fuel.
The Pratt & Whitney J58 is an American jet engine that powered the Lockheed A-12, and subsequently the YF-12 and the SR-71 aircraft. It was an afterburning turbojet engine with a unique compressor bleed to the afterburner that gave increased thrust at high speeds. Because of the wide speed range of the aircraft, the engine needed two modes of operation to take it from stationary on the ground to 2,000 mph (3,200 km/h) at altitude. It was a conventional afterburning turbojet for take-off and acceleration to Mach 2 and then used permanent compressor bleed to the afterburner above Mach 2. The way the engine worked at cruise led it to be described as "acting like a turboramjet". It has also been described as a turboramjet based on incorrect statements describing the turbomachinery as being completely bypassed.
Jet fuel or aviation turbine fuel is a type of aviation fuel designed for use in aircraft powered by gas-turbine engines. It is colorless to straw-colored in appearance. The most commonly used fuels for commercial aviation are Jet A and Jet A-1, which are produced to a standardized international specification. The only other jet fuel commonly used in civilian turbine-engine powered aviation is Jet B, which is used for its enhanced cold-weather performance.
Gear oil is a lubricant made specifically for transmissions, transfer cases, and differentials in automobiles, trucks, and other machinery. It has high viscosity and usually contains organosulfur compounds. Some modern automatic transaxles do not use a heavy oil at all but lubricate with the lower viscosity hydraulic fluid, which is available at pressure within the automatic transmission. Gear oils account for about 20% of the lubricant market.
A coolant is a substance, typically liquid, that is used to reduce or regulate the temperature of a system. An ideal coolant has high thermal capacity, low viscosity, is low-cost, non-toxic, chemically inert and neither causes nor promotes corrosion of the cooling system. Some applications also require the coolant to be an electrical insulator.
Turbine Fuel Low Volatility JP-7, commonly known as JP-7 is a specialized type of jet fuel developed in 1955 for the United States Air Force (USAF) for use in its supersonic military aircraft, including the SR-71 Blackbird and the Boeing X-51 Waverider.
Fuel system icing inhibitor (FSII) is an additive to aviation fuels that prevents the formation of ice in fuel lines. FSII is sometimes referred to by the registered, genericized trademark Prist. Jet fuel can contain a small amount of dissolved water that does not appear in droplet form. As an aircraft gains altitude, the temperature drops and the fuel's capacity to hold water is diminished. Dissolved water can separate out and could become a serious problem if it freezes in fuel lines or filters, blocking the flow of fuel and shutting down an engine.
JP-8, or JP8, is a jet fuel, specified and used widely by the US military. It is specified by MIL-DTL-83133 and British Defence Standard 91-87, and similar to commercial aviation's Jet A-1, but with the addition of corrosion inhibitor and anti-icing additives.
JP-4, or JP4 was a jet fuel, specified in 1951 by the United States Department of Defense (MIL-DTL-5624). Its NATO code is F-40. It is also known as avtag.
Dexron is the trade name for a group of technical specifications for automatic transmission fluid (ATF) created by General Motors (GM). The name was first registered as a trademark and later evolved into a brand of GM. GM licenses the name and specifications to companies that manufacture the fluid and sell it under their own brand names. Not all Dexron fluids are licensed by GM for reselling under another brand name. To be licensed, the product must have a license number that begins with the letters B through J and include a "Dexron Approved" sticker on its container. Like many automobile manufacturers, GM uses transmissions sourced from other suppliers or transmission manufacturers around the world; many of these may use their own unique fluid.
In aeronautics, ice protection systems keep atmospheric moisture from accumulating on aircraft surfaces, such as wings, propellers, rotor blades, engine intakes, and environmental control intakes. Ice buildup can change the shape of airfoils and flight control surfaces, degrading control and handling characteristics as well as performance. An anti-icing, de-icing, or ice protection system either prevents formation of ice, or enables the aircraft to shed the ice before it becomes dangerous.
Charcoal lighter fluid is a flammable fluid used to accelerate the ignition of charcoal in a barbecue grill. It can either be petroleum based or alcohol based. It can be used both with lump charcoal and briquettes. Lighter-fluid infused briquettes, that eliminate the need for separate application of lighter fluid, are available. The use of lighter fluid is somewhat controversial as the substance is combustible, harmful or fatal if swallowed, and may impart an unpleasant flavor to food cooked upon fires lit with it.
In ground deicing of aircraft, aircraft deicing fluid (ADF), aircraft deicer and anti-icer fluid (ADAF) or aircraft anti-icing fluid (AAF) are commonly used for both commercial and general aviation. Environmental concerns include increased salinity of groundwater where de-icing fluids are discharged into soil, and toxicity to humans and other mammals.
Aircraft engine performance refers to factors including thrust or shaft power for fuel consumed, weight, cost, outside dimensions and life. It includes meeting regulated environmental limits which apply to emissions of noise and chemical pollutants, and regulated safety aspects which require a design that can safely tolerate environmental hazards such as birds, rain, hail and icing conditions. It is the end product that an engine company sells.
{{cite web}}
: CS1 maint: archived copy as title (link){{cite journal}}
: Cite journal requires |journal=
(help)