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124-618: The GAA powered several models and derivatives of the M4A3 Sherman medium tank. After the start of World War II, UK was looking to manufacture complicated parts (notably the crankshafts) of the Rolls-Royce Merlin in the US, but negotiations with Packard stalled because the company insisted on making complete engines. In June 1940 production drawings arrived in North America and were seized by

248-521: A bulldozer blade, the Duplex Drive system, flamethrowers for Zippo flame tanks , and various rocket launchers such as the T34 Calliope . British variants (DDs and mine flails ) formed part of the group of specialized vehicles collectively known as " Hobart's Funnies " (after Percy Hobart , commander of the 79th Armoured Division ). The M4 Sherman's basic chassis was used for all the sundry roles of

372-454: A coil of fiber optic cable as long as 5 km. Like the ring laser gyroscope , it makes use of the Sagnac effect . A London moment gyroscope relies on the quantum-mechanical phenomenon, whereby a spinning superconductor generates a magnetic field whose axis lines up exactly with the spin axis of the gyroscopic rotor. A magnetometer determines the orientation of the generated field, which

496-593: A few hundred hours test-bed running by that time. It was a liquid-cooled Vee similar to the Meteor, but two-third the size and Rolls-Royce executive W. A. Robotham doubted its reliability at 600 bhp. The 600 bhp Meteor was designed to fit in the same space in the Crusader (tank) as the Nuffield Liberty L-12 engine of 340 bhp output. The Ford V8 developed only 500 bhp, and had problems which were not overcome until after

620-403: A fluid, instead of being mounted in gimbals. A control moment gyroscope (CMG) is an example of a fixed-output-gimbal device that is used on spacecraft to hold or maintain a desired attitude angle or pointing direction using the gyroscopic resistance force. In some special cases, the outer gimbal (or its equivalent) may be omitted so that the rotor has only two degrees of freedom. In other cases,

744-422: A force applied to the input axis by a reaction force to the output axis. A gyroscope flywheel will roll or resist about the output axis depending upon whether the output gimbals are of a free or fixed configuration. An example of some free-output-gimbal devices is the attitude control gyroscopes used to sense or measure the pitch, roll and yaw attitude angles in a spacecraft or aircraft. The centre of gravity of

868-463: A gyroscope (the "Whirling Speculum" or "Serson's Speculum") was invented by John Serson in 1743. It was used as a level, to locate the horizon in foggy or misty conditions. The first instrument used more like an actual gyroscope was made by Johann Bohnenberger of Germany, who first wrote about it in 1817. At first he called it the "Machine". Bohnenberger's machine was based on a rotating massive sphere. In 1832, American Walter R. Johnson developed

992-421: A gyroscope with a weight on one of the axes. The device will react to the force generated by the weight when it is accelerated, by integrating that force to produce a velocity. A gyrostat consists of a massive flywheel concealed in a solid casing. Its behaviour on a table, or with various modes of suspension or support, serves to illustrate the curious reversal of the ordinary laws of static equilibrium due to

1116-411: A gyroscope with two gimbals, the outer gimbal, which is the gyroscope frame, is mounted so as to pivot about an axis in its own plane determined by the support. This outer gimbal possesses one degree of rotational freedom and its axis possesses none. The second gimbal, inner gimbal, is mounted in the gyroscope frame (outer gimbal) so as to pivot about an axis in its own plane that is always perpendicular to

1240-404: A human hair viewed from 32 kilometers (20 mi) away. The GP-B gyro consists of a nearly-perfect spherical rotating mass made of fused quartz , which provides a dielectric support for a thin layer of niobium superconducting material. To eliminate friction found in conventional bearings, the rotor assembly is centered by the electric field from six electrodes. After the initial spin-up by

1364-471: A jet of helium which brings the rotor to 4,000 RPM , the polished gyroscope housing is evacuated to an ultra-high vacuum to further reduce drag on the rotor. Provided the suspension electronics remain powered, the extreme rotational symmetry , lack of friction, and low drag will allow the angular momentum of the rotor to keep it spinning for about 15,000 years. A sensitive DC SQUID that can discriminate changes as small as one quantum, or about 2 × 10 Wb ,

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1488-676: A key component of the Allied war effort. The Sherman's role as the backbone of U.S. armored forces in World War II cemented its legacy as one of the most influential tank designs of the 20th century. Despite its limitations—such as relatively thin armor compared to German heavy tanks like the Tiger and Panther —the M4 was designed to be both affordable and adaptable. Its widespread deployment, durability, and ease of maintenance ensured it remained in service throughout

1612-627: A magnetic compass, it does not seek north. When being used in an airplane, for example, it will slowly drift away from north and will need to be reoriented periodically, using a magnetic compass as a reference. Unlike a directional gyro or heading indicator, a gyrocompass seeks north. It detects the rotation of the Earth about its axis and seeks the true north, rather than the magnetic north. Gyrocompasses usually have built-in damping to prevent overshoot when re-calibrating from sudden movement. By determining an object's acceleration and integrating over time,

1736-724: A modern mechanized force. These included the M10 and M36 tank destroyers; M7B1 , M12 , M40 , and M43 self-propelled artillery; the M32 and M74 "tow truck"-style recovery tanks with winches, booms, and an 81 mm mortar for smoke screens; and the M34 (from M32B1) and M35 (from M10A1) artillery prime movers . Pullman-Standard Car Company American Locomotive Co. Baldwin Locomotive Works Federal Machine and Welder Co. During World War II, approximately 19,247 Shermans were issued to

1860-424: A more capable but heavier tank. Tank destroyer battalions using vehicles built on the M4 hull and chassis, but with open-topped turrets and more potent high-velocity guns, also entered widespread use in the Allied armies. Even by 1944, most M4 Shermans kept their dual-purpose 75 mm gun. By then, the M4 was inferior in firepower and armor to increasing numbers of German upgraded medium tanks and heavy tanks but

1984-497: A more efficient and versatile design, leading to the development of the M4 Sherman. The M4 Sherman retained much of the mechanical design of the M3, but it addressed several shortcomings and incorporated improvements in mobility, firepower, and ergonomics. One of the most significant changes was the relocation of the main armament—initially a 75 mm gun—into a fully traversing turret located at

2108-594: A pivotal role in the success of the Allied forces. In terms of tank production, the only World War II-era tank to exceed the M4’s production numbers was the Soviet T-34 , with approximately 64,549 units built. On the battlefield, the Sherman was particularly effective against German light and medium tanks during the early stages of the war, notably between 1939 and 1942. Its 75 mm gun and relatively superior armor provided an edge over

2232-440: A position between the low-accuracy, low-cost MEMS gyroscope and the higher-accuracy and higher-cost fiber optic gyroscope. Accuracy parameters are increased by using low-intrinsic damping materials, resonator vacuumization, and digital electronics to reduce temperature dependent drift and instability of control signals. High quality wine-glass resonators are used for precise sensors like HRG. A dynamically tuned gyroscope (DTG)

2356-465: A production program calling for 120,000 tanks for the Allied war effort. Although the American industrial complex was not affected by enemy aerial bombing or submarine warfare as was Japan , Germany and, to a lesser degree, Great Britain , an enormous amount of steel for tank production was diverted to the construction of warships and other naval vessels. Steel used in naval construction amounted to

2480-497: A similar device that was based on a rotating disc. The French mathematician Pierre-Simon Laplace , working at the École Polytechnique in Paris, recommended the machine for use as a teaching aid, and thus it came to the attention of Léon Foucault . In 1852, Foucault used it in an experiment demonstrating the rotation of the Earth. It was Foucault who gave the device its modern name, in an experiment to see (Greek skopeein , to see)

2604-407: A single integrated circuit package, providing inexpensive and widely available motion sensing. All spinning objects have gyroscopic properties. The main properties that an object can experience in any gyroscopic motion are rigidity in space and precession . Rigidity in space describes the principle that a gyroscope remains in the fixed position on the plane in which it is spinning, unaffected by

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2728-570: A speed of 24,000 revolutions per minute in less than 10 seconds. Gyroscopes continue to be an engineering challenge. For example, the axle bearings have to be extremely accurate. A small amount of friction is deliberately introduced to the bearings, since otherwise an accuracy of better than 10 − 7 {\displaystyle 10^{-7}} of an inch (2.5 nm) would be required. Three-axis MEMS-based gyroscopes are also used in portable electronic devices such as tablets , smartphones , and smartwatches . This adds to

2852-460: A stop. This feature proved useful in ensuring the tank could quickly take aim after halting to fire, enhancing its effectiveness in combat. However, by modern standards, this system was relatively rudimentary compared to more advanced stabilizers. The development of the M4 Sherman emphasized key factors such as reliability, ease of production, and standardization. The U.S. Army and the designers prioritized durability and maintenance ease, which ensured

2976-535: A tank designed by the Canadian General Staff, also influenced the development of the American Sherman tank. Before long American military agencies and designers had accumulated sufficient experience to forge ahead on several points. In the field of tank armament, the American 75 mm and 76 mm dual-purpose tank guns won the acknowledgment of British tank experts. Detailed design characteristics for

3100-443: A thick stem. This shell is driven to a flexural resonance by electrostatic forces generated by electrodes which are deposited directly onto separate fused-quartz structures that surround the shell. Gyroscopic effect is obtained from the inertial property of the flexural standing waves. A vibrating structure gyroscope (VSG), also called a Coriolis vibratory gyroscope (CVG), uses a resonator made of different metallic alloys. It takes

3224-782: A third of the battalions and none of the divisions were deployed to the Pacific Theater. The Imperial Japanese Army (IJA) deployed only their 1st Tank Division and 2nd Tank Division to the Pacific during the war with the 3rd Tank Division being deployed in Burma , China and Manchukuo 's border with the Soviet Union and the 4th Tank Division remaining on the Japanese home islands in preparation for an allied invasion that never came. Armor from both sides mostly operated in jungle terrain that

3348-405: A toy gyroscope with a pull string and pedestal. Manufacture was at some point switched to Chandler Mfg Co (still branded Hurst). The product was later renamed to a “Chandler gyroscope”, presumably because Chandler Mfg Co. took over rights to the gyroscope. Chandler continued to produce the toy until the company was purchased by TEDCO Inc. in 1982. The gyroscope is still produced by TEDCO today. In

3472-550: A typical U.S. infantry division had attached for armor support an M4 Sherman battalion, a tank destroyer battalion, or both. After World War II, the Sherman, particularly the many improved and upgraded versions, continued to see combat service in many conflicts around the world, including the UN forces in the Korean War , with Israel in the Arab–Israeli wars , briefly with South Vietnam in

3596-504: A unique design that featured the main armament mounted in a side sponson. The Grant variant, used by British forces, employed a lower-profile turret based on British designs, while the Lee variant, used by the United States, retained the original American turret design. Despite the M3's effectiveness, the tank’s unconventional layout and the limitations of its hull-mounted gun prompted the need for

3720-548: A vehicle with the 76 mm gun, B for the 105 mm howitzer, C for the 17-pounder gun, and Y for any vehicle equipped with horizontal volute spring suspension (HVSS), e.g. British operated M4A1(76) was known as Sherman IIA. Early Shermans mounted a 75 mm medium-velocity general-purpose gun . Although Ordnance began work on the T20/22/23 series as Sherman replacements, the Army Ground Forces were satisfied with

3844-457: Is interpolated to determine the axis of rotation. Gyroscopes of this type can be extremely accurate and stable. For example, those used in the Gravity Probe B experiment measured changes in gyroscope spin axis orientation to better than 0.5 milliarcseconds (1.4 × 10 degrees, or about 2.4 × 10  radians ) over a one-year period. This is equivalent to an angular separation the width of

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3968-471: Is a miniaturized gyroscope found in electronic devices. It takes the idea of the Foucault pendulum and uses a vibrating element. This kind of gyroscope was first used in military applications but has since been adopted for increasing commercial use. The hemispherical resonator gyroscope (HRG), also called a wine-glass gyroscope or mushroom gyro, makes use of a thin solid-state hemispherical shell, anchored by

4092-426: Is a rotor suspended by a universal joint with flexure pivots. The flexure spring stiffness is independent of spin rate. However, the dynamic inertia (from the gyroscopic reaction effect) from the gimbal provides negative spring stiffness proportional to the square of the spin speed (Howe and Savet, 1964; Lawrence, 1998). Therefore, at a particular speed, called the tuning speed, the two moments cancel each other, freeing

4216-403: Is an instrument, consisting of a wheel mounted into two or three gimbals providing pivoted supports, for allowing the wheel to rotate about a single axis. A set of three gimbals, one mounted on the other with orthogonal pivot axes, may be used to allow a wheel mounted on the innermost gimbal to have an orientation remaining independent of the orientation, in space, of its support. In the case of

4340-427: Is designed to minimize Lorentz torque on the rotor. The main rotor of a helicopter acts like a gyroscope. Its motion is influenced by the principle of gyroscopic precession which is the concept that a force applied to a spinning object will have a maximum reaction approximately 90 degrees later. The reaction may differ from 90 degrees when other stronger forces are in play. To change direction, helicopters must adjust

4464-471: Is in offensive operations against hostile rear areas. The M4 was, therefore, not originally intended primarily as an infantry support tank . It placed tanks in the "striking echelon" of the armored division and placed the infantry in the "support echelon", without directing that tanks should only seek to attack other tanks, thus leaving target selection up to the field commander based on what types of units were available to him to attack. A field manual covering

4588-517: Is represented by spin, θ {\displaystyle \theta } is the nutation angle, and I {\displaystyle I} represents inertia along its respective axis. This relation is only valid with the Moment along the Y and Z axes are equal to 0. The equation can be further reduced noting that the angular velocity along the z-axis is equal to the sum of the Precession and

4712-481: Is the rate of change of the angular momentum that is produced by the applied torque. Precession produces counterintuitive dynamic results such as a spinning top not falling over. Precession is used in aerospace applications for sensing changes of attitude and direction. A Steadicam rig was employed during the filming of the 1983 film Return of the Jedi , in conjunction with two gyroscopes for extra stabilization, to film

4836-465: Is used to monitor the gyroscope. A precession , or tilt, in the orientation of the rotor causes the London moment magnetic field to shift relative to the housing. The moving field passes through a superconducting pickup loop fixed to the housing, inducing a small electric current. The current produces a voltage across a shunt resistance, which is resolved to spherical coordinates by a microprocessor. The system

4960-497: The Axis nations . The T6 prototype was completed on 2 September 1941. The upper hull of the T6 was a single large casting. It featured a single overhead hatch for the driver and a hatch in the side of the hull. In the later M4A1 production model, this large casting was maintained, although the side hatch was eliminated, and a second overhead hatch was added for the assistant driver. The modified T6

5084-621: The Hubble Space Telescope , or inside the steel hull of a submerged submarine. Due to their precision, gyroscopes are also used in gyrotheodolites to maintain direction in tunnel mining. Gyroscopes can be used to construct gyrocompasses , which complement or replace magnetic compasses (in ships, aircraft and spacecraft, vehicles in general), to assist in stability (bicycles, motorcycles, and ships) or be used as part of an inertial guidance system . MEMS gyroscopes are popular in some consumer electronics, such as smartphones. A gyroscope

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5208-638: The Korean War , the M4A3E8 Easy Eight was the main tank force of the U.S. military until the signing of the armistice agreement. At the outbreak of the war, the U.S. military tried to deploy the M4A3E8, a medium-sized tank of the same class, to respond to North Korean T-34-85, but there were few tanks available for rapid deployment from the Far East due to disarmament after World War II. The U.S. Far East Command collected 58 M4A3E8 scattered throughout Japan, created

5332-720: The Lend-Lease program to the British Commonwealth , Soviet Union , and other Allied Nations . The tank was named by the British after the American Civil War General William Tecumseh Sherman . The M4 Sherman tank evolved from the M3 Lee , a medium tank developed by the United States during the early years of World War II. The M3, also known by its service names "Grant" and "Lee," was characterized by

5456-673: The Republic of Korea Marine Corps during the war while the Army operated M36 GMCs as its main armored asset. After World War II, the U.S. kept the M4A3E8 Easy Eight in service, with either the 76 mm gun or a 105 mm M4 howitzer. The U.S. Army replaced the M4 in 1957, in favor of the M47 Patton , M48 Patton and, M60 Patton . The U.S. continued to transfer Shermans to its allies, which contributed to widespread foreign use. The Israeli Defense Force used Shermans from its creation in 1948 until

5580-898: The Second Battle of El Alamein in October 1942 with the British 8th Army . At the start of the offensive, there were 252 tanks fit for action. These equipped the British 9th Armoured Brigade (for the battle under the New Zealand Division ), 2nd Armoured Brigade (1st Armoured Division), and 8th and 20th Armoured Brigades (10th Armoured Division). Their first encounter with tanks was against German Panzer III and IV tanks with long 50 mm and 75 mm guns engaging them at 2,000 yards (1,800 m). There were losses to both sides. The first U.S. Shermans in battle were M4s and M4A1s in Operation Torch

5704-596: The Sherman Firefly ). Some were fitted with a 105 mm howitzer to act as infantry support vehicles. The relative ease of production allowed large numbers of the M4 to be manufactured, and significant investment in tank recovery and repair units allowed disabled vehicles to be repaired and returned to service quickly. These factors combined to give the Allies numerical superiority in most battles, and many infantry divisions were provided with M4s and tank destroyers. By 1944,

5828-522: The US Treasury Department , that's when Ford engineers were able to copy them and soon derive a clone simplified for industrial production at Ford's factories. It was a 60 degree V-12 of 1,650 cubic inch displacement with cylinder bore and stroke matching the Merlin aviation engine, using an aluminum block and head ; dual overhead camshafts , and four valves per cylinder. The intention of this design

5952-581: The Vietnam War , and on both sides of the Indo-Pakistani War of 1965 . The United States Army Ordnance Department designed the M4 medium tank as a replacement for the M3 medium tank. The M3 was an up-gunned development of the M2 medium tank of 1939, in turn, derived from the M2 light tank of 1935. The M3 was developed as a stopgap measure until a new turret mounting a 75 mm gun could be devised. While it

6076-430: The 1967 Six-Day War. Gyrostabilizer A gyroscope (from Ancient Greek γῦρος gŷros , "round" and σκοπέω skopéō , "to look") is a device used for measuring or maintaining orientation and angular velocity . It is a spinning wheel or disc in which the axis of rotation (spin axis) is free to assume any orientation by itself. When rotating, the orientation of this axis is unaffected by tilting or rotation of

6200-553: The 1980s, having first acquired a single M4A2 lacking the main armament from British forces as they withdrew from Israel. The popularity of the tank (having now been re-armed) compared to the outdated, 1934-origin French Renault R35 interwar light tanks with their 37 mm short-barreled guns, which made up the bulk of the IDF's tank force, led to the purchase of 30 unarmed M4(105 mm)s from Italian scrapyards. Three of these, plus

6324-508: The 3-axis acceleration sensing ability available on previous generations of devices. Together these sensors provide 6 component motion sensing; accelerometers for X, Y, and Z movement, and gyroscopes for measuring the extent and rate of rotation in space (roll, pitch and yaw). Some devices additionally incorporate a magnetometer to provide absolute angular measurements relative to the Earth's magnetic field. Newer MEMS-based inertial measurement units incorporate up to all nine axes of sensing in

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6448-550: The 8072nd Temporary Tank Battalion (later renamed to the 89th Tank Battalion) on 17 July and landed them in Busan on 1 August. The 8072nd Temporary Tank Battalion was immediately deployed for Battle of Masan to support the 25th U.S. Infantry Division. Since then, a total of 679 M4A3E8 were deployed on the Korean Peninsula in 1950. The M4A3E8 and T-34 -85 were comparable and could destroy each other at normal combat ranges, although

6572-570: The American tanks to the British ones, but preferred Soviet ones most of all. While combat in the European theater often consisted of high-profile armored warfare, the mainly naval nature of the Pacific Theater of Operations (PTO) relegated it to secondary status for both the Allies and the Japanese. While the U.S. Army fielded 16 armored divisions and 70 separate tank battalions during the war, only

6696-573: The Army accepted a limited run of 254 M4A3E2 "Jumbo" Shermans, which had very thick hull armor and the 75 mm gun in a new, better-protected T23-style turret ("Jumbos" could mount the 76 mm M1 cannon), to assault fortifications, leading convoys, and spearhead armored columns. The M4A3 model was the first to be factory-produced with the HVSS system with wider tracks to distribute weight, beginning in August 1944. With

6820-469: The Army's contractual commitments to existing manufacturers. With the approach of war, increasing orders for M4 Sherman tanks were causing supply issues with the 9-cylinder radial Wright R-975 Whirlwind engine used. The U.S. Army decided it needed to source additional engine suppliers, choosing a version of the Ford GAA cut down from twelve cylinders to eight for various vehicle applications. In 1942 after

6944-585: The British Tank Mission visit to America in April, there was some pressure from British car and commercial vehicle manufacturers to use the new Ford V8 tank engine designed by Larry Sheldrick in British tanks, rather than the Meteor then under development by Rolls-Royce from the Merlin aero engine, as they believed that an adapted aero engine "would not be suitable as a rugged tank engine". The Ford engine prototype had

7068-507: The British tank mission in the U.S., the tank was displayed in London and is now an exhibit at The Tank Museum , Bovington, UK. In World War II, the U.S. Army ultimately fielded 16 armored divisions, along with 70 separate tank battalions, while the U.S. Marine Corps fielded six tank battalions. A third of all Army tank battalions, and all six Marine tank battalions, were deployed to the Pacific Theater of Operations (PTO). Before September 1942, President Franklin D. Roosevelt had announced

7192-559: The Earth's rotation (Greek gyros , circle or rotation), which was visible in the 8 to 10 minutes before friction slowed the spinning rotor. In the 1860s, the advent of electric motors made it possible for a gyroscope to spin indefinitely; this led to the first prototype heading indicators , and a rather more complicated device, the gyrocompass . The first functional gyrocompass was patented in 1904 by German inventor Hermann Anschütz-Kaempfe . American Elmer Sperry followed with his own design later that year, and other nations soon realized

7316-436: The Earth's rotation. For example, a bike wheel. Early forms of gyroscope (not then known by the name) were used to demonstrate the principle. A simple case of precession, also known as steady precession, can be described by the following relation to Moment: where ϕ ′ {\displaystyle \phi '} represents precession, ψ ′ {\displaystyle \psi '}

7440-609: The Israeli Army upgraded about 180 M4A1(76)W HVSS Shermans with the French 105 mm Modèle F1 gun, re-engined them with Cummins diesel engines, and designated the upgraded tank Sherman M-51 . The Sherman tanks, fighting alongside the 105 mm Centurion Shot Kal and M48 Patton tanks, were able to defeat the T-34-85, T-54/55/62 series, and IS-3 tanks used by the Egyptian and Syrian forces in

7564-462: The M3's 75 mm gun. This would later become the Sherman. The Sherman's reliability resulted from many features developed for U.S. light tanks during the 1930s, including vertical volute spring suspension , rubber-bushed tracks, and a rear-mounted radial engine with drive sprockets in front. The goals were to produce a fast, dependable medium tank able to support infantry, provide breakthrough striking capacity, and defeat any tank then in use by

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7688-453: The M4 and Armored Force Board considered some features of the experimental tanks unsatisfactory. Continuing with M4 minimized production disruption but elements of the experimental designs were incorporated into the Sherman. Later M4A1, M4A2, and M4A3 models received the larger turret with high velocity 76 mm gun trialed on the T23 tank. The first standard-production 76 mm gun-armed Sherman

7812-465: The M4 was submitted by the Ordnance Department on 31 August 1940, but the development of a prototype was delayed while the final production designs of the M3 were finished and the M3 entered full-scale production. On 18 April 1941, the U.S. Armored Force Board chose the simplest of five designs. Known as the T6, the design was a modified M3 hull and chassis, carrying a newly designed turret mounting

7936-517: The M4A1 differed from the other variants by its fully cast upper hull, with a distinctive rounded appearance. The M4A4 had a longer engine that required a longer hull and more track blocks, and thus the most distinguishing feature of the M4A4 was the wider longitudinal spacing between the bogies. "M4A5" was an administrative placeholder designation for Canadian Ram tank . The M4A6 had a radial diesel engine as well as

8060-567: The Middle East as quickly as possible." The US considered collecting all Shermans together to be able to send the 2nd Armored Division under Patton to reinforce Egypt, but delivering the Shermans directly to the British was quicker and over 300 – mostly M4A1s, but also including M4A2s – had arrived there by September 1942. The Shermans were modified for desert warfare with shields over the tracks and another stowage. The Sherman first saw combat at

8184-669: The Normandy landings in 1944. M4 Sherman The M4 Sherman , officially medium tank, M4 , was the medium tank most widely used by the United States and Western Allies in World War II . The M4 Sherman proved to be reliable, relatively cheap to produce, and available in great numbers. It was also the basis of several other armored fighting vehicles including self-propelled artillery , tank destroyers , and armored recovery vehicles . Tens of thousands were distributed through

8308-734: The Pacific. However, the Chief of the Army's Armored Force, Lt. Gen. Jacob L. Devers , ordered that no diesel-engined Shermans be used by the Army outside the Zone of Interior (the continental U.S.). The Army used all types for either training or testing within the United States but intended the M4A2 and M4A4 (with the A57 Multibank engine) to be the primary Lend-Lease exports. Shermans were being issued in small numbers for familiarization to U.S. armored divisions when there

8432-476: The Sherman. Such units included the 1st Guards Mechanized Corps , the 3rd Guards Mechanized Corps and the 9th Guards Mechanized Corps , amongst others. According to Soviet tanker Dmitriy Loza, the Sherman was held in good regard and viewed positively by many Soviet tank crews, with compliments given to its reliability, ease of maintenance, generally good firepower (referring especially to the 76 mm gun version) as well as an auxiliary power unit (APU) to keep

8556-400: The Spin: ω z = ϕ ′ cos ⁡ θ + ψ ′ {\displaystyle \omega _{z}=\phi '\cos \theta +\psi '} , Where ω z {\displaystyle \omega _{z}} represents the angular velocity along the z axis. or Gyroscopic precession is torque induced. It

8680-422: The U.S. Army and about 1,114 to the U.S. Marine Corps. The U.S. also supplied 17,184 to United Kingdom (some of which in turn went to the Canadians and the Free Poles), while the Soviet Union received 4,102 and an estimated 812 were transferred to China . These numbers were distributed further to the respective countries' allied nations. The U.S. Marine Corps used the diesel M4A2 and gasoline powered M4A3 in

8804-458: The United States approached entry into World War II, armored employment was doctrinally governed by Field Manual 100–5, Operations (published May 1941, the month following selection of the M4 tank's final design). That field manual stated: The armored division is organized primarily to perform missions that require great mobility and firepower. It is given decisive missions. It is capable of engaging in all forms of combat, but its primary role

8928-462: The advantage of Allied armor over Axis armor and was superior to the lighter German and Italian tank designs. For this reason, the US Army believed that the M4 would be adequate to win the war, and relatively little pressure was initially applied for further tank development. Logistical and transport restrictions, such as limitations imposed by roads, ports, and bridges, also complicated the introduction of

9052-411: The background plates for the speeder bike chase. Steadicam inventor Garrett Brown operated the shot, walking through a redwood forest, running the camera at one frame per second. When projected at 24 frames per second, it gave the impression of flying through the air at perilous speeds. The heading indicator or directional gyro has an axis of rotation that is set horizontally, pointing north. Unlike

9176-403: The center of the vehicle. This design allowed for more flexible and accurate fire control, enabling the crew to engage targets with greater precision than was possible on the M3. Additionally, the M4 featured a one-axis gyrostabilizer , which, while not precise enough to allow for accurate firing while in motion, helped keep the gun roughly aimed in the direction of the target when the tank came to

9300-440: The centre of gravity of the rotor may be offset from the axis of oscillation, and thus the centre of gravity of the rotor and the centre of suspension of the rotor may not coincide. Essentially, a gyroscope is a top combined with a pair of gimbals . Tops were invented in many different civilizations, including classical Greece, Rome, and China. Most of these were not utilized as instruments. The first known apparatus similar to

9424-423: The demands of mass production and quick deployment. The M4 Sherman was designed to be more versatile and easier to produce than previous models, which proved vital as the United States entered World War II. It became the most-produced American tank of the conflict, with a total of 49,324 units built, including various specialized variants. Its production volume surpassed that of any other American tank, and it played

9548-434: The device was at rest at the extremities of its shaking motion. This was cured by applying a random white noise to the vibration. The material of the block was also changed from quartz to a new glass ceramic Cer-Vit , made by Owens Corning , because of helium leaks. A fiber optic gyroscope also uses the interference of light to detect mechanical rotation. The two-halves of the split beam travel in opposite directions in

9672-544: The elongated chassis of the M4A4, but only 75 of these were ever produced. Most Sherman sub-types ran on gasoline. The air-cooled Continental-produced Wright R-975 Whirlwind 9-cylinder radial gasoline engine in the M4 and M4A1 produced 350 or 400 horsepower (260 or 300 kW). The M4A3 used the liquid-cooled 450 hp (340 kW) Ford GAA V8 gasoline engine, and the M4A4 used the liquid-cooled 370 hp (280 kW) 30 cylinder Chrysler A57 multibank gasoline engine. There were also two diesel-engined variants. The M4A2

9796-520: The equations of motion of a gyrostat. Examples include a solid body with a cavity filled with an inviscid, incompressible, homogeneous liquid, the static equilibrium configuration of a stressed elastic rod in elastica theory , the polarization dynamics of a light pulse propagating through a nonlinear medium, the Lorenz system in chaos theory, and the motion of an ion in a Penning trap mass spectrometer. A microelectromechanical systems (MEMS) gyroscope

9920-553: The equivalent of approximately 67,000 tanks; and consequently, only about 53,500 tanks were produced during 1942 and 1943. The Army had seven main sub-designations for M4 variants during production: M4, M4A1, M4A2, M4A3, M4A4, M4A5, and M4A6. These designations did not necessarily indicate linear improvement; in that "M4A4" did not indicate it was better than "M4A3". These sub-types indicated standardized production variations, which were often manufactured concurrently at different locations. The sub-types differed mainly in engines, although

10044-436: The ether. In modern continuum mechanics there is a variety of these models, based on ideas of Lord Kelvin. They represent a specific type of Cosserat theories (suggested for the first time by Eugène Cosserat and François Cosserat ), which can be used for description of artificially made smart materials as well as of other complex media. One of them, so-called Kelvin's medium, has the same equations as magnetic insulators near

10168-488: The experimental models went through many changes before it was deemed ready for production by the engineers and managers of Honeywell and Boeing . It was an outcome of the competition with mechanical gyroscopes, which kept improving. The reason Honeywell, of all companies, chose to develop the laser gyro was that they were the only one that didn't have a successful line of mechanical gyroscopes, so they wouldn't be competing against themselves. The first problem they had to solve

10292-472: The first several decades of the 20th century, other inventors attempted (unsuccessfully) to use gyroscopes as the basis for early black box navigational systems by creating a stable platform from which accurate acceleration measurements could be performed (in order to bypass the need for star sightings to calculate position). Similar principles were later employed in the development of inertial navigation systems for ballistic missiles . During World War II,

10416-569: The following month. On 6 December, near Tebourba, Tunisia , a platoon from the 2nd Battalion, 13th Armored Regiment was lost to enemy tanks and anti-tank guns. Additional M4s and M4A1s replaced M3s in U.S. tank battalions over the course of the North African campaign. The M4 and M4A1 were the main types in U.S. units until the fall of 1944 when the Army began replacing them with the preferred M4A3 with its more powerful 500 hp (370 kW) engine. Some M4s and M4A1s continued in U.S. service for

10540-473: The front during the beginning of any attack. The first production of the Sherman took place at the Lima Locomotive Works and was first used in 1941, with many early vehicles reserved for British use under Lend-Lease; the first production Sherman was given to the U.S. Army for evaluation, and the second tank of the British order went to London. Nicknamed Michael , probably after Michael Dewar, head of

10664-416: The gyroscope became the prime component for aircraft and anti-aircraft gun sights. After the war, the race to miniaturize gyroscopes for guided missiles and weapons navigation systems resulted in the development and manufacturing of so-called midget gyroscopes that weighed less than 3 ounces (85 g) and had a diameter of approximately 1 inch (2.5 cm). Some of these miniaturized gyroscopes could reach

10788-410: The gyrostatic behaviour of the interior invisible flywheel when rotated rapidly. The first gyrostat was designed by Lord Kelvin to illustrate the more complicated state of motion of a spinning body when free to wander about on a horizontal plane, like a top spun on the pavement, or a bicycle on the road. Kelvin also made use of gyrostats to develop mechanical theories of the elasticity of matter and of

10912-413: The heavier Type 4 Chi-To ; both tanks were armed with 75 mm guns, albeit of different type. Only 166 Type 3s and two Type 4s were built, and none saw combat; they were saved for the defense of the Japanese home islands , leaving 1930s era light and medium armor to do battle against 1940s-built Allied light and medium armor. During the later years of the war, general purpose high explosive ammunition

11036-407: The military importance of the invention—in an age in which naval prowess was the most significant measure of military power—and created their own gyroscope industries. The Sperry Gyroscope Company quickly expanded to provide aircraft and naval stabilizers as well, and other gyroscope developers followed suit. Circa 1911 the L. T. Hurst Mfg Co of Indianapolis started producing the "Hurst gyroscope"

11160-419: The mounting, according to the conservation of angular momentum . Gyroscopes based on other operating principles also exist, such as the microchip-packaged MEMS gyroscopes found in electronic devices (sometimes called gyrometers ), solid-state ring lasers , fibre optic gyroscopes , and the extremely sensitive quantum gyroscope . Applications of gyroscopes include inertial navigation systems , such as in

11284-523: The original 75 mm main gun, with 2,095 mounting the more-capable 76 mm gun. The total number of Sherman tanks sent to the USSR under Lend-Lease represented 18.6% of all Lend-Lease Shermans. The first 76 mm-armed M4A2 Shermans started to arrive in the Soviet Union in the late summer of 1944. The Soviet records reported the receiving of 3,664 tanks; the difference mainly due to deliveries being sunk on

11408-437: The original M4A2, saw extensive service in the 1948-9 war of independence. The remainder were then serviced and rearmed with 75 mm guns and components whenever these became available, composing a large part of Israeli tank forces for the next eight years. The 75 mm-armed Shermans were replaced by M4A1 (76 mm) Shermans imported from France before the 1956 Suez Crisis after it was realized that their armor penetration

11532-415: The pitch angle and the angle of attack. Gyro X prototype vehicle created by Alex Tremulis and Thomas Summers in 1967. The car utilized gyroscopic precession to drive on two wheels. An assembly consisting of a flywheel mounted in a gimbal housing under the hood of the vehicle acted as a large gyroscope. The flywheel was rotated by hydraulic pumps creating a gyroscopic effect on the vehicle. A precessional ram

11656-400: The pivotal axis of the gyroscope frame (outer gimbal). This inner gimbal has two degrees of rotational freedom. The axle of the spinning wheel (the rotor) defines the spin axis. The rotor is constrained to spin about an axis, which is always perpendicular to the axis of the inner gimbal. So the rotor possesses three degrees of rotational freedom and its axis possesses two. The rotor responds to

11780-412: The preferred U.S. tank in the later phases of the war. It was considered more advantageous in terms of maneuverability on rough terrain and ease of maintenance due to the mechanical reliability. Because of this feature, the M4A3E8 were widely used for providing close support to infantry units, particularly during battles for high ground and mountains. From December 1951, around 20 M4A3E8s saw service with

11904-682: The rest of the war. The first Sherman to enter combat with the 76 mm gun in July 1944 was the M4A1, then the M4A2, closely followed by the M4A3. By the end of the war, roughly half the U.S. Army Shermans in Europe had the 76 mm gun. The first HVSS-equipped Sherman to see combat was the M4A3(76)W in December 1944. Under Lend-Lease, 4,102 M4A2 medium tanks were sent to the Soviet Union. Of these, 2,007 were equipped with

12028-401: The rotor can be in a fixed position. The rotor simultaneously spins about one axis and is capable of oscillating about the two other axes, and it is free to turn in any direction about the fixed point (except for its inherent resistance caused by rotor spin). Some gyroscopes have mechanical equivalents substituted for one or more of the elements. For example, the spinning rotor may be suspended in

12152-495: The rotor from torque, a necessary condition for an ideal gyroscope. A ring laser gyroscope relies on the Sagnac effect to measure rotation by measuring the shifting interference pattern of a beam split into two separate beams which travel around the ring in opposite directions. When the Boeing 757 -200 entered service in 1983, it was equipped with the first suitable ring laser gyroscope. This gyroscope took many years to develop, and

12276-471: The smooth ride of the HVSS, it gained the nickname " Easy Eight " from its experimental "E8" designation. The M4 and M4A3 105 mm-armed tanks, as well as the M4A1 and M4A2 76 mm-armed tanks, were also eventually equipped with HVSS. Both the Americans and the British developed a wide array of special attachments for the Sherman, although few saw combat, remaining experimental. Those that saw action included

12400-468: The state of magnetic saturation in the approximation of quasimagnetostatics. In modern times, the gyrostat concept is used in the design of attitude control systems for orbiting spacecraft and satellites. For instance, the Mir space station had three pairs of internally mounted flywheels known as gyrodynes or control moment gyroscopes . In physics, there are several systems whose dynamical equations resemble

12524-482: The tank could be quickly repaired in the field. A critical aspect of the design process was the standardization of parts, allowing for streamlined production and the efficient supply of replacement components. Additionally, the tank's size and weight were kept within moderate limits, which facilitated easier shipping and compatibility with existing logistical and engineering equipment, including bridges and transport vehicles. These design principles were essential for meeting

12648-422: The tank's basic model number. These included stronger suspension units, safer "wet" (W) ammunition stowage, and stronger or more effective armor arrangements, such as the M4 "Composite", which had a cheaper to produce cast front hull section mated to a regular welded rear hull. British nomenclature for Shermans was by mark numbers for the different hulls with letters for differences in armament and suspension: A for

12772-683: The tank's batteries charged without having to run the main engine, as was required on the T-34. However, according to Soviet tank crews, the Sherman also had disadvantages, the greatest being its high center of gravity and the ease of hitting it by enemy fire. The Sherman’s relatively narrow-set tracks struggled to negotiate muddy terrain compared to the wider-set tracks of the T-34 or German Panther tank. David M. Glantz wrote: "[The Sherman’s] narrow treads made it much less mobile on mud than its German and Soviet counterparts, and it consumed great quantities of fuel..." Glantz noted that Soviet tankers preferred

12896-640: The tanks fielded by Nazi Germany during this period. The M4 Sherman saw widespread use across various theaters of combat, including North Africa, Italy, and Western Europe. It was instrumental in the success of several Allied offensives, particularly after 1942, when the Allies began to gain momentum following the Allied landings in North Africa (Operation Torch) and the subsequent campaigns in Italy and France. The tank’s ability to be produced in large numbers, combined with its operational flexibility and effectiveness, made it

13020-509: The time M4s reached combat in significant numbers, battlefield demands for infantry support and tank-versus-tank action far outnumbered the occasional opportunities of rear-echelon exploitation. United States doctrine held that the most critical anti-tank work – stopping massed enemy tank attacks – was primarily to be done by towed and self-propelled anti-tank guns, operated by "Tank Destroyer" battalions , with friendly tanks being used in support if possible. Speed

13144-470: The use of High-Velocity Armor Piercing ammunition, advanced optics, and better crew training gave the Sherman an advantage. The M4A3E8, using 76 mm HVAP ammunition, destroyed 41 enemy tanks from July to November 1950. The M4A3E8 had weaker anti-tank combat capability compared to the larger caliber M26 Pershing and the M46 Patton that were operated at the same time. However, the lighter M4A3E8 became

13268-400: The use of the Sherman (FM 17–33, "The Tank Battalion, Light and Medium" of September 1942) described fighting enemy tanks, when necessary, as one of the many roles of the Sherman, but devoted only one page of text and four diagrams to tank-versus-tank action out of 142 pages. This early armored doctrine was heavily influenced by the sweeping early war successes of German blitzkrieg tactics. By

13392-434: The velocity of the object can be calculated. Integrating again, position can be determined. The simplest accelerometer is a weight that is free to move horizontally, which is attached to a spring and a device to measure the tension in the spring. This can be improved by introducing a counteracting force to push the weight back and to measure the force needed to prevent the weight from moving. A more complicated design consists of

13516-521: The war, and it continued to see action even in the years following World War II in various conflicts and regions. The M4 Sherman remains one of the most iconic tanks in military history, symbolizing the industrial might and innovation of the United States during the war. When the M4 tank went into combat in North Africa with the British Army at the Second Battle of El Alamein in late 1942, it increased

13640-474: The way and discrepancies between the United States and Soviet Union archives The Red Army considered the M4A2 to be much less prone to catch fire due to ammunition detonation than the T-34/76 , but the M4A2 had a higher tendency to overturn in road accidents and collisions or because of rough terrain than the T-34 due to its higher center of gravity. By 1945, some Red Army armored units were equipped entirely with

13764-492: Was a big improvement when used by the British in Africa against German forces , the placement of a 37 mm gun turret on top gave it a very high profile, and the unusual side-sponson mounted main gun, with limited traverse , could not be aimed across the other side of the tank. Though reluctant to adopt British weapons into their arsenal, the American designers were prepared to accept proven British ideas. These ideas, as embodied in

13888-628: Was a turn of events in the Western Desert campaign . On 21 June 1942, Axis forces captured Tobruk , threatening Egypt and Britain's supply line through the Suez Canal . British Prime Minister Winston Churchill was at the Second Washington Conference when news of the defeat broke; President Franklin D. Roosevelt asked what he could do to help and Churchill replied at once, "Give us as many Sherman tanks as you can spare and ship them to

14012-437: Was able to fight on with the help of considerable numerical superiority, greater mechanical reliability, better logistical support, and support from growing numbers of fighter-bombers and artillery pieces. Later in the war, a more effective armor-piercing gun, the 76 mm gun M1 , was incorporated into production vehicles. For anti-tank work, the British refitted Shermans with a 76.2 mm Ordnance QF 17-pounder gun (as

14136-504: Was an M4A1, accepted in January 1944, which first saw combat in July 1944 during Operation Cobra . Variants of the M4 and M4A3 were factory-produced with a 105 mm howitzer and a distinctive rounded gun mantlet , which surrounded the main gun, on the turret. The first Sherman variant to be armed with the 105 mm howitzer was the M4, first accepted in February 1944. From May to July 1944,

14260-404: Was essential to bring the tank destroyers from the rear to destroy incoming tanks. This doctrine was rarely followed in combat, as it was found to be impractical. Commanders were reluctant to leave tank destroyers in reserve; if they were, it was also easier for an opposing armored force to achieve a breakthrough against an American tank battalion, which would not have all of its anti-tank weapons at

14384-662: Was insufficient for combat against newer tanks such as the IDF Centurions as well as the T-34-85s being delivered to Egyptian forces. During further upgrades, the French military helped develop a conversion kit to upgrade about 300 Shermans to the long high-velocity 75 mm gun CN 75-50 used in the AMX-13 . These were designated Sherman M-50 by the Israelis. Before the Six-Day War in 1967,

14508-673: Was newer by five years. By 1943, the IJA still used the Type 95 and Type 97 Chi-Ha medium tanks, while Allied forces were quickly replacing their light tanks with 75 mm-armed M4s. The Chinese in India received 100 M4 Shermans and used them to great effect in the subsequent 1944 and 1945 offensives in the China Burma India Theater . To counter the Sherman, the Japanese developed the Type 3 Chi-Nu and

14632-578: Was poorly suited to armored warfare. For this type of terrain, the Japanese and the Allies found light tanks easier to transport and deploy. During the early stages of combat in the Pacific, specifically, the Guadalcanal Campaign , the U.S. Marine Corps' M2A4 light tank fought against the equally matched Type 95 Ha-Go light tank; both were armed with a 37 mm main gun. However, the M2 (produced in 1940)

14756-470: Was powered by a pair of liquid-cooled GMC Detroit Diesel 6–71 two-stroke inline engines, that produced a total of 375 hp (280 kW), while the M4A6 used an RD-1820 (a redesigned Caterpillar D-200A air-cooled radial diesel engine, adapted from Wright Aeronautical 's Wright R-1820 Cyclone 9 nine-cylinder radial aircraft engine. ) that produced 450 hp (340 kW). A 24-volt electrical system

14880-484: Was preferred for fighting Japanese tanks because armor-piercing rounds, which had been designed for penetrating thicker steel, often went through the thin armor of the Type 95 Ha-Go (the most commonly encountered Japanese tank) and out the other side without stopping . Although the high-velocity guns of tank destroyers were useful for penetrating fortifications, M4s armed with flamethrowers were often deployed, as direct fire seldom destroyed Japanese fortifications. During

15004-529: Was standardized as the M4, and first production completed in February 1942. The cast-hull models would later be re-standardized as M4A1, with the first welded-hull models receiving the designation M4. In August 1942, a variant of the M4 was put forth by the Detroit Arsenal to have angled, rather than rounded hull and turret armor. The changes were intended to improve the tank's protection without increasing weight or degrading other technical characteristics. As

15128-444: Was that with laser gyros rotations below a certain minimum could not be detected at all, due to a problem called "lock-in", whereby the two beams act like coupled oscillators and pull each other's frequencies toward convergence and therefore zero output. The solution was to shake the gyro rapidly so that it never settled into lock-in. Paradoxically, too regular of a dithering motion produced an accumulation of short periods of lock-in when

15252-542: Was to help Ford break into the anticipated large market for aircraft engines. This engine was built to typical aircraft standards: it was light, high performance, and highly reliable. Everything was safety wired or staked with close attention to detail on every part. Available information suggests this design performed well. However, it never went into production as an aircraft engine due to the United States Navy's decision to only use radial engines for its aircraft and

15376-403: Was used in the M4. The M4A2 and M4A4 were mostly supplied to other Allied countries under Lend-Lease . The term "M4" can refer specifically to the initial sub-type with its Continental radial engine, or generically, to the entire family of seven Sherman sub-types, depending on context. Many details of production, shape, strength, and performance improved while in production, without a change to

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