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62-594: The Ryan FR Fireball is an American mixed-power ( piston and jet-powered ) fighter aircraft designed by Ryan Aeronautical for the United States Navy during World War II . It was the Navy's first aircraft with a jet engine . Only 66 aircraft were built before Japan surrendered in August 1945. The FR-1 Fireball equipped a single squadron before the war's end, but did not see combat. The aircraft ultimately proved to lack

124-430: A fluid or solid as a response to a pressure (or mean stress ) change. In its simple form, the compressibility κ {\displaystyle \kappa } (denoted β in some fields) may be expressed as where V is volume and p is pressure. The choice to define compressibility as the negative of the fraction makes compressibility positive in the (usual) case that an increase in pressure induces

186-413: A real gas from those expected from an ideal gas . The compressibility factor is defined as where p is the pressure of the gas, T is its temperature , and V m {\displaystyle V_{m}} is its molar volume , all measured independently of one another. In the case of an ideal gas, the compressibility factor Z is equal to unity, and the familiar ideal gas law

248-459: A 1,600 lbf (7,100 N) General Electric I-16 (later redesignated as the J-31) turbojet was mounted in the rear fuselage . It was fed by ducts in each wing root which meant that the wing had to be relatively thick to house the ducts and the outward-retracting main landing gear. To simplify the fuel system, both engines used the same grade of avgas . Two self-sealing fuel tanks were housed in

310-409: A Fireball of VF-41 became the first aircraft to land under jet power on an aircraft carrier, albeit without prior planning, on 6 November 1945. After the radial engine of an FR-1 failed on final approach to the escort carrier Wake Island , the pilot managed to start the jet engine and land, barely catching the last arrestor wire before hitting the ship's crash barrier. However, there is evidence that

372-597: A capacity of 1,820 L (64 cu ft), making a total capacity of 25,480 L (900 cu ft) for the largest versions. For piston engines, an engine's capacity is the engine displacement , in other words the volume swept by all the pistons of an engine in a single movement. It is generally measured in litres (l) or cubic inches (c.i.d., cu in, or in ) for larger engines, and cubic centimetres (abbreviated cc) for smaller engines. All else being equal, engines with greater capacities are more powerful and consumption of fuel increases accordingly (although this

434-698: A circular groove in the piston head. The rings fit closely in the groove and press lightly against the cylinder wall to form a seal, and more heavily when higher combustion pressure moves around to their inner surfaces. It is common to classify such engines by the number and alignment of cylinders and total volume of displacement of gas by the pistons moving in the cylinders usually measured in cubic centimetres (cm or cc) or litres (l) or (L) (US: liter). For example, for internal combustion engines, single and two-cylinder designs are common in smaller vehicles such as motorcycles , while automobiles typically have between four and eight, and locomotives and ships may have

496-469: A cylinder to drive a reciprocating engine in a local-pollution-free urban vehicle. Torpedoes may use a working gas produced by high test peroxide or Otto fuel II , which pressurize without combustion. The 230 kg (510 lb) Mark 46 torpedo , for example, can travel 11 km (6.8 mi) underwater at 74 km/h (46 mph) fuelled by Otto fuel without oxidant . Quantum heat engines are devices that generate power from heat that flows from

558-418: A dozen cylinders or more. Cylinder capacities may range from 10 cm or less in model engines up to thousands of liters in ships' engines. The compression ratio affects the performance in most types of reciprocating engine. It is the ratio between the volume of the cylinder, when the piston is at the bottom of its stroke, and the volume when the piston is at the top of its stroke. The bore/stroke ratio

620-408: A fluid has strong implications for its dynamics. Most notably, the propagation of sound is dependent on the compressibility of the medium. Compressibility is an important factor in aerodynamics . At low speeds, the compressibility of air is not significant in relation to aircraft design, but as the airflow nears and exceeds the speed of sound , a host of new aerodynamic effects become important in

682-420: A great deal of energy in a reversible process and this greatly reduces the thermodynamic temperature of hypersonic gas decelerated near the aerospace object. Ions or free radicals transported to the object surface by diffusion may release this extra (nonthermal) energy if the surface catalyzes the slower recombination process. For ordinary materials, the bulk compressibility (sum of the linear compressibilities on

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744-527: A hard landing. Subsequent inspections of the squadron's aircraft showed signs of structural failure and all the Fireballs were withdrawn by 1 August 1947. After the withdrawal of the type from service, except for a few examples retained for modifications and testing, the FR-1s were scrapped. The "Firebirds" squadron was known under three names: Only a single example, FR-1 BuNo 39657, still survives. Deployed first to

806-406: A hot to a cold reservoir. The mechanism of operation of the engine can be described by the laws of quantum mechanics . Quantum refrigerators are devices that consume power with the purpose to pump heat from a cold to a hot reservoir. In a reciprocating quantum heat engine, the working medium is a quantum system such as spin systems or a harmonic oscillator. The Carnot cycle and Otto cycle are

868-441: A large number of unusual varieties of piston engines that have various claimed advantages, many of which see little if any current use: Compressibility#Aeronautical dynamics In thermodynamics and fluid mechanics , the compressibility (also known as the coefficient of compressibility or, if the temperature is held constant, the isothermal compressibility ) is a measure of the instantaneous relative volume change of

930-403: A reciprocating engine is proportional to the volume of the combined pistons' displacement. A seal must be made between the sliding piston and the walls of the cylinder so that the high pressure gas above the piston does not leak past it and reduce the efficiency of the engine. This seal is usually provided by one or more piston rings . These are rings made of a hard metal, and are sprung into

992-422: A reduction in volume. The reciprocal of compressibility at fixed temperature is called the isothermal bulk modulus . The specification above is incomplete, because for any object or system the magnitude of the compressibility depends strongly on whether the process is isentropic or isothermal . Accordingly, isothermal compressibility is defined: where the subscript T indicates that the partial differential

1054-532: A result of the changes in airflow from an incompressible fluid (similar in effect to water) to a compressible fluid (acting as a gas) as the speed of sound is approached. There are two effects in particular, wave drag and critical mach . One complication occurs in hypersonic aerodynamics, where dissociation causes an increase in the "notional" molar volume because a mole of oxygen, as O 2 , becomes 2 moles of monatomic oxygen and N 2 similarly dissociates to 2 N. Since this occurs dynamically as air flows over

1116-480: A sequence of strokes that admit and remove gases to and from the cylinder. These operations are repeated cyclically and an engine is said to be 2-stroke , 4-stroke or 6-stroke depending on the number of strokes it takes to complete a cycle. The most common type is 4-stroke, which has following cycles. The reciprocating engine developed in Europe during the 18th century, first as the atmospheric engine then later as

1178-497: A single-slotted flap. The first prototype was lost in a crash at NAS China Lake on 13 October 1944. Investigation showed that the wing structure was not strong enough to resist compressibility effects . This was cured by doubling the number of rivets in the outer wing panels. The second prototype crashed on 25 March 1945 when the pilot failed to recover from a dive from 35,000 feet (10,670 m), probably also due to compressibility effects. The third prototype crashed on 5 April when

1240-813: A testbed for the turbojet installation on the XF2R-1 Dark Shark . This was the final variant; the piston engine was replaced with a General Electric XT31-GE-2 turboprop , but only one prototype was built. On 2 December 1943, orders for 100 production FR-1s were placed, with a follow-up order of 1,000 additional fighters in January 1945. All of the contracts were contingent on the aircraft successfully completing carrier trials. Only 66 Fireballs were completed by November 1945 as orders for 1,044 FR-1s were canceled on VJ Day . One squadron, VF-66 , received its first Fireballs in March 1945, but they never saw combat. On 1 May, three of

1302-418: Is incomplete, both beta (the volume/pressure differential ratio) and the differential, constant pressure heat capacity greatly increases. For moderate pressures, above 10,000 K the gas further dissociates into free electrons and ions. Z for the resulting plasma can similarly be computed for a mole of initial air, producing values between 2 and 4 for partially or singly ionized gas. Each dissociation absorbs

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1364-433: Is inside a cylinder , into which a gas is introduced, either already under pressure (e.g. steam engine ), or heated inside the cylinder either by ignition of a fuel air mixture ( internal combustion engine ) or by contact with a hot heat exchanger in the cylinder ( Stirling engine ). The hot gases expand, pushing the piston to the bottom of the cylinder. This position is also known as the bottom dead center (BDC), or where

1426-586: Is not to be confused with fuel efficiency , since high efficiency often requires a lean fuel-air ratio, and thus lower power density. A modern high-performance car engine makes in excess of 75 kW/L (1.65 hp/in ). Reciprocating engines that are powered by compressed air, steam or other hot gases are still used in some applications such as to drive many modern torpedoes or as pollution-free motive power. Most steam-driven applications use steam turbines , which are more efficient than piston engines. The French-designed FlowAIR vehicles use compressed air stored in

1488-412: Is not true of every reciprocating engine), although power and fuel consumption are affected by many factors outside of engine displacement. Reciprocating engines can be characterized by their specific power , which is typically given in kilowatts per litre of engine displacement (in the U.S. also horsepower per cubic inch). The result offers an approximation of the peak power output of an engine. This

1550-428: Is recovered: Z can, in general, be either greater or less than unity for a real gas. The deviation from ideal gas behavior tends to become particularly significant (or, equivalently, the compressibility factor strays far from unity) near the critical point , or in the case of high pressure or low temperature. In these cases, a generalized compressibility chart or an alternative equation of state better suited to

1612-401: Is the thermal pressure coefficient . In an extensive thermodynamic system, the application of statistical mechanics shows that the isothermal compressibility is also related to the relative size of fluctuations in particle density: where μ is the chemical potential . The term "compressibility" is also used in thermodynamics to describe deviations of the thermodynamic properties of

1674-394: Is the fictitious pressure which would produce the same amount of net work that was produced during the power stroke cycle. This is shown by: where A p {\displaystyle A_{p}} is the total piston area of the engine, S {\displaystyle S} is the stroke length of the pistons, and V d {\displaystyle V_{d}}

1736-459: Is the ratio of the diameter of the piston, or " bore ", to the length of travel within the cylinder, or "stroke". If this is around 1 the engine is said to be "square". If it is greater than 1, i.e. the bore is larger than the stroke, it is "oversquare". If it is less than 1, i.e. the stroke is larger than the bore, it is "undersquare". Cylinders may be aligned in line , in a V configuration , horizontally opposite each other, or radially around

1798-425: Is the total displacement volume of the engine. Therefore: Whichever engine with the larger value of MEP produces more net work per cycle and performs more efficiently. In steam engines and internal combustion engines, valves are required to allow the entry and exit of gases at the correct times in the piston's cycle. These are worked by cams, eccentrics or cranks driven by the shaft of the engine. Early designs used

1860-423: Is then fed through one or more, increasingly larger bore cylinders successively, to extract power from the steam at increasingly lower pressures. These engines are called compound engines . Aside from looking at the power that the engine can produce, the mean effective pressure (MEP), can also be used in comparing the power output and performance of reciprocating engines of the same size. The mean effective pressure

1922-417: Is to be taken at constant temperature. Isentropic compressibility is defined: where S is entropy. For a solid, the distinction between the two is usually negligible. Since the density ρ of a material is inversely proportional to its volume, it can be shown that in both cases For instance, for an ideal gas , Consequently, the isothermal compressibility of an ideal gas is The ideal gas (where

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1984-452: The D slide valve but this has been largely superseded by piston valve or poppet valve designs. In steam engines the point in the piston cycle at which the steam inlet valve closes is called the cutoff and this can often be controlled to adjust the torque supplied by the engine and improve efficiency. In some steam engines, the action of the valves can be replaced by an oscillating cylinder . Internal combustion engines operate through

2046-874: The NASA Ames Research Center , the aircraft served as an instructional airframe at a technical school before being acquired by the Planes of Fame Air Museum at Chino, California from a technical school located in San Luis Obispo, California in the 1960s. After restoration to static display condition, 39657 was rolled out at Chino on 13 June 2009. Data from United States Navy Aircraft since 1911 and Ryan FR-1 Fireball and XF2R-1 Darkshark General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists Reciprocating engine There may be one or more pistons. Each piston

2108-450: The escort carrier Charger in early January 1945. The aircraft successfully made five catapult takeoffs using the piston engine as well as three takeoffs using both engines. No problems were reported when landing aboard the carrier. The FR-1 Fireball was further developed into the XFR-2 which utilized a 1,425 hp (1,063 kW) Wright R-1820-74W in place of the -72W. One single airframe

2170-470: The steam engine . These were followed by the Stirling engine and internal combustion engine in the 19th century. Today the most common form of reciprocating engine is the internal combustion engine running on the combustion of petrol , diesel , liquefied petroleum gas (LPG) or compressed natural gas (CNG) and used to power motor vehicles and engine power plants . One notable reciprocating engine from

2232-483: The World War II era was the 28-cylinder, 3,500  hp (2,600 kW) Pratt & Whitney R-4360 Wasp Major radial engine. It powered the last generation of large piston-engined planes before jet engines and turboprops took over from 1944 onward. It had a total engine capacity of 71.5 L (4,360 cu in), and a high power-to-weight ratio . The largest reciprocating engine in production at present, but not

2294-436: The aerospace object, it is convenient to alter the compressibility factor Z , defined for an initial 30 gram moles of air, rather than track the varying mean molecular weight, millisecond by millisecond. This pressure dependent transition occurs for atmospheric oxygen in the 2,500–4,000 K temperature range, and in the 5,000–10,000 K range for nitrogen. In transition regions, where this pressure dependent dissociation

2356-447: The aircraft may have still benefited from some residual power from its Wright R-1820 and therefore the landing was not purely under jet power. The squadron was attempting to qualify its pilots for carrier operations during this time, but only 14 of its 22 pilots made the six required takeoffs and landings. A number of accidents occurred when the nose gear failed on landing, but the pilots were at least partly responsible as they were slamming

2418-549: The canopy blew off during a high-speed pass over Lindbergh Field . Operational testing by the Naval Air Test Center at Naval Air Station Patuxent River that included carrier acceptability tests revealed additional problems: The piston engine tended to overheat until electrically operated cowl flaps were installed, the catapult hooks had to be moved, and the nosewheel oleo shock strut had to be lengthened by 3 inches (76 mm). Carrier suitability tests began aboard

2480-413: The center section of the wing, immediately outboard of the air intakes for the jet engine. Four 5-inch (127 mm) rockets could be carried under each outer wing panel and two hardpoints were provided under the center section for 1,000 lb (454 kg) bombs or 100 US gal (380 L; 83 imp gal) drop tanks . Armor plates were provided in front and behind the pilot's seat and for

2542-431: The compressibility can be determined for any substance. The speed of sound is defined in classical mechanics as: It follows, by replacing partial derivatives , that the isentropic compressibility can be expressed as: The inverse of the compressibility is called the bulk modulus , often denoted K (sometimes B or β {\displaystyle \beta } ).). The compressibility equation relates

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2604-470: The crankshaft. Opposed-piston engines put two pistons working at opposite ends of the same cylinder and this has been extended into triangular arrangements such as the Napier Deltic . Some designs have set the cylinders in motion around the shaft, such as the rotary engine . In some steam engines, the cylinders may be of varying size with the smallest bore cylinder working the highest pressure steam. This

2666-506: The cylinder by this stroke . The exception is the Stirling engine , which repeatedly heats and cools the same sealed quantity of gas. The stroke is simply the distance between the TDC and the BDC, or the greatest distance that the piston can travel in one direction. In some designs the piston may be powered in both directions in the cylinder, in which case it is said to be double-acting . In most types,

2728-441: The design of aircraft. These effects, often several of them at a time, made it very difficult for World War II era aircraft to reach speeds much beyond 800 km/h (500 mph). Many effects are often mentioned in conjunction with the term "compressibility", but regularly have little to do with the compressible nature of air. From a strictly aerodynamic point of view, the term should refer only to those side-effects arising as

2790-399: The first two prototypes delivered in 14 months. Another contract was placed for 100 aircraft on 2 December 1943 and a later contract on 31 January 1945 increased the total of FR-1s on order to 700. The XFR-1 was a single-seat, low-wing monoplane with tricycle landing gear . A 1,350-horsepower (1,010 kW) Wright R-1820-72W Cyclone radial engine was mounted in the fighter's nose while

2852-515: The fuselage, one of 130 US gallons (490 L; 110 imp gal) and the other of 50 US gallons (190 L; 42 imp gal). The cockpit was positioned just forward of the leading edge of the wing and the pilot was provided with a bubble canopy which gave him excellent visibility. The XFR-1 had the first laminar flow airfoil in a navy carrier aircraft. The Fireball was armed with four .50 in (12.7 mm) M2 Browning machine guns with 300 rounds per gun. They were mounted in

2914-521: The isothermal compressibility (and indirectly the pressure) to the structure of the liquid. The isothermal compressibility is generally related to the isentropic (or adiabatic ) compressibility by a few relations: where γ is the heat capacity ratio , α is the volumetric coefficient of thermal expansion , ρ = N / V is the particle density, and Λ = ( ∂ P / ∂ T ) V {\displaystyle \Lambda =(\partial P/\partial T)_{V}}

2976-588: The largest ever built, is the Wärtsilä-Sulzer RTA96-C turbocharged two-stroke diesel engine of 2006 built by Wärtsilä . It is used to power the largest modern container ships such as the Emma Mærsk . It is five stories high (13.5 m or 44 ft), 27 m (89 ft) long, and weighs over 2,300 metric tons (2,535 short tons ; 2,264 long tons ) in its largest 14 cylinders version producing more than 84.42 MW (113,209 bhp). Each cylinder has

3038-416: The linear movement of the piston is converted to a rotating movement via a connecting rod and a crankshaft or by a swashplate or other suitable mechanism. A flywheel is often used to ensure smooth rotation or to store energy to carry the engine through an un-powered part of the cycle. The more cylinders a reciprocating engine has, generally, the more vibration-free (smoothly) it can operate. The power of

3100-494: The nose gear onto the deck after landing on the main gear. The squadron qualified on the escort carrier Bairoko in March 1946, but nose gear problems persisted and cut the cruise short. Ryan installed a steel fork for the nosewheel, but inspections also revealed evidence of partial wing failures so the aircraft was limited to maneuvers not to exceed 5 Gs . VF-41 suffered three fatal accidents in 1946 before being redesignated as VF-1E on 15 November 1946. One ensign collided with

3162-463: The oil cooler. The first XFR-1 made its first flight on 25 June 1944 without its jet engine, but this was installed shortly afterward. The second prototype first flew on 20 September 1944. Test flights confirmed wind tunnel tests that revealed a lack of longitudinal stability because the center of gravity had been miscalculated. In addition, the circular rear fuselage of the FR-1 gave less stability than

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3224-410: The ones most studied. The quantum versions obey the laws of thermodynamics . In addition, these models can justify the assumptions of endoreversible thermodynamics . A theoretical study has shown that it is possible and practical to build a reciprocating engine that is composed of a single oscillating atom. This is an area for future research and could have applications in nanotechnology . There are

3286-418: The particles do not interact with each other) is an abstraction. The particles in real materials interact with each other. Then, the relation between the pressure, density and temperature is known as the equation of state denoted by some function F {\displaystyle F} . The Van der Waals equation is an example of an equation of state for a realistic gas. Knowing the equation of state,

3348-423: The piston forms the largest volume in the cylinder. The piston is returned to the cylinder top (top dead center) (TDC) by a flywheel , the power from other pistons connected to the same shaft or (in a double acting cylinder ) by the same process acting on the other side of the piston. This is where the piston forms the smallest volume in the cylinder. In most types the expanded or " exhausted " gases are removed from

3410-483: The problem must be utilized to produce accurate results. The Earth sciences use compressibility to quantify the ability of a soil or rock to reduce in volume under applied pressure. This concept is important for specific storage , when estimating groundwater reserves in confined aquifers . Geologic materials are made up of two portions: solids and voids (or same as porosity ). The void space can be full of liquid or gas. Geologic materials reduce in volume only when

3472-492: The slab-style fuselage of the Grumman F4F Wildcat that was used as a model for the stability calculations. A new tail with enlarged vertical and horizontal stabilizers was designed and retrofitted to the prototypes. The original Douglas double-slotted flaps proved to be unsatisfactory during flight testing, but all three prototypes and the first 14 production aircraft were built with them before they were replaced with

3534-544: The squadron's aircraft were craned aboard the carrier Ranger to attempt to qualify seven pilots, but two of the fighters were damaged while landing. One missed the arresting gear and hit the crash barrier while the other aircraft's nose gear collapsed. The following month the pilots qualified and were on pre- embarkation leave when the Japanese surrendered. The squadron was decommissioned on 18 October with all pilots and aircraft transferred to VF-41 . It has been claimed that

3596-500: The structural strength required for operations aboard aircraft carriers and was withdrawn in mid-1947. Design of the FR-1 began in 1943 to a proposal instigated by Admiral John S. McCain Sr. for a mixed-powered fighter because early jet engines had sluggish acceleration that was considered unsafe and unsuitable for carrier operations. Ryan received a contract for three XFR-1 prototypes and one static test airframe on 11 February 1943 with

3658-596: The target banner during gunnery practice and spun into the water. A few months later, the squadron commander was performing a barrel roll when his wing broke off and he struck another Fireball, killing both pilots. VF-1E conducted carrier qualification in March 1947 aboard the escort carrier Badoeng Strait and only eight pilots successfully qualified, not least because the FR-1s were proving to be too fragile to endure repeated carrier landings. During one brief deployment in June aboard Rendova , one aircraft broke in two during

3720-509: The void spaces are reduced, which expel the liquid or gas from the voids. This can happen over a period of time, resulting in settlement . It is an important concept in geotechnical engineering in the design of certain structural foundations. For example, the construction of high-rise structures over underlying layers of highly compressible bay mud poses a considerable design constraint, and often leads to use of driven piles or other innovative techniques. The degree of compressibility of

3782-402: The wing roots to the fuselage in front of the wing; they were covered by electrically powered doors to lessen drag when the aircraft was flying only on its piston engine. The Fireball's fuselage was lengthened by 8 inches (203 mm) to accommodate the larger engine and the leading edge extension of the wing root that housed the air intakes was also removed. The XFR-4 was intended to serve as

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3844-507: Was converted to this configuration. No prototypes were built for the next proposed variant, the FR-3, which would have used a General Electric I-20 turbojet. Both of these projects were canceled with the end of the war. The fastest Fireball was the XFR-4, which had a Westinghouse J34 turbojet and was approximately 100 mph (160 km/h) faster than the FR-1. The turbojet's air intakes were moved from

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