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89-652: In 1937, the Polikarpov design bureau carried out studies to improve on the performance of its I-15 and I-15bis biplane fighters without sacrificing manoeuvrability, as Soviet tactical doctrine was based on a mix of high performance monoplane fighters (met by the Polikarpov I-16 ) and agile biplanes. Early combat experience from the Spanish Civil War had shown that the I-16 had problems dealing with

178-455: A stall , so the FAA emphasizes training pilots in stall recognition, prevention, and recovery as a means to reduce accidents due to unintentional stalls or spins. A spin is often intimidating to the uninitiated, however many pilots trained in spin entry and recovery find that the experience builds awareness and confidence. In a spin, the occupants of the airplane only feel reduced gravity during

267-507: A Heinkel two-seater to crash-land. No losses were reported among the Soviet pilots. During the next two days, Chato pilots claimed 12 more victories, at the cost of two I-15s lost. On 16 November, while dogfighting with Fiat CR.32s over Madrid, future ace Rychagov was shot down and four days later the number of combat-ready Polikarpov in the central area had fallen to 15 aircraft: seven had been lost in combat, two had force-landed and one

356-531: A development of the I-5 fighter became the famous I-15 . The first flight was made in October 1933 with V.P. Chkalov at the controls, powered by an imported Wright R-1820 Cyclone engine. The I-15, also known by its development name TsKB-3 , was a small biplane fighter with a gulled upper wing. The single bay wings were of wooden construction, while the fuselage was of mixed steel and duralumin construction, with

445-415: A differential induced drag that raises the nose toward a level pitch attitude. As the nose comes up the tail moves out farther from the center of rotation increasing lateral airflow over the empennage. The increase in lateral flow across the vertical stabilizer/rudder brings it to its critical angle of attack stalling it. The normal recovery input of opposite rudder further increases angle of attack, deepening

534-786: A fabric covered rear fuselage. Production started in 1934, initially being powered by the Shvetsov M-22, a licence-built version of the Bristol Jupiter radial engine . While less powerful than the Cyclone, the M-22 powered aircraft were still superior to the I-5 which it replaced, demonstrating excellent manoeuvrability. Production switched to the 515 kW (691 hp) Shvetsov M-25 engine (a license-built, metricified Cyclone) in late 1936. A total of 671 I-15s were built, 284 in

623-410: A pilot's instinct to pull back on the stick served only to make a spin worse. Because of this, the spin earned a reputation as an unpredictable danger that might snatch an aviator's life at any time, and against which there was no defense. In early aviation, individual pilots explored spins by performing ad-hoc experiments (often accidentally), and aerodynamicists examined the phenomenon. Lincoln Beachey

712-500: A pitch test. To do this, slowly reduce power to idle and see which way the nose pitches. If it pitches down, then the aircraft is stall recoverable. If the nose pitches up, then the stall would be difficult to recover or altogether unrecoverable. The pitch test should be done just prior to performing a spin maneuver. If the center of gravity of the airplane is behind the aft limit approved for spinning, any spin may prove unrecoverable except by using some special spin-recovery device such as

801-513: A service ceiling of 9,800 m (32,100 ft). This performance was disappointing, and caused the aircraft to fail the state acceptance trials, although this did not disrupt production. While it was recognised that the I-153's performance was inadequate, the over-riding requirement was to not disrupt production until more advanced fighters could enter production. While numerous improvements were proposed, many were too radical to be implemented since

890-578: A small number of airplane types the FAA has made a finding of equivalent level of safety (ELOS) so that demonstration of a one-turn spin is not necessary. For example, this has been done with the Cessna Corvalis and the Cirrus SR20/22 . Successful demonstration of the one-turn spin does not get an airplane approved for intentional spinning. To get an airplane approved for intentional spinning,

979-522: A spin of at least one turn, while single-engine aircraft certified in the utility category must demonstrate a six-turn spin that cannot be unrecoverable at any time during the spin due to pilot action or aerodynamic characteristic. NASA recommends various tail configurations and other strategies to eliminate the flatter of the two spin modes and make recovery from the steeper mode more reliable. In aviation's early days, spins were poorly understood and often fatal. Proper recovery procedures were unknown, and

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1068-420: A spin, the spin has four phases. At low altitude, spin recovery may also be impossible before impacting terrain, making low and slow aircraft especially vulnerable to spin-related accidents. Spins can be classified using the following descriptors: The U.S. National Aeronautics and Space Administration ( NASA ) has defined four different modes of spinning. These four modes are defined by the angle of attack of

1157-489: A spin-recovery parachute specially installed in the tail of the airplane; or by jettisoning specially installed ballast at the tail of the airplane. Some World War II airplanes were notoriously prone to spins when loaded erroneously; for example, the Bell P-39 Airacobra . The P-39 was an unusual design with the engine behind the pilot's seat and a large cannon in the front. Soviet pilots did numerous tests of

1246-506: A spin. Generally, though, spin training is undertaken in an "Unusual attitude recovery course" or as a part of an aerobatics endorsement (though not all countries actually require training for aerobatics). However, understanding and being able to recover from spins is certainly a skill that a fixed-wing pilot could learn for safety. It is routinely given as part of the training in sailplanes , since gliders often operate slowly enough to be in near-stall conditions while turning. Because of this, in

1335-677: A stall and wing drop (the very beginning of the entry to a spin) and must recover from a stall and wing drop as part of training. Some aircraft cannot be recovered from a spin using only their own flight control surfaces and must not be allowed to enter a spin under any circumstances. If an aircraft has not been certified for spin recovery, it should be assumed that spins are not recoverable and are unsafe in that aircraft. Important safety equipment, such as stall/spin recovery parachutes , which generally are not installed on production aircraft, are used during testing and certification of aircraft for spins and spin recovery. Spin-entry procedures vary with

1424-421: A test pilot must repeatedly subject it to a spin of six turns and then demonstrate recovery within one and a half additional turns. Spin testing is a potentially hazardous exercise, and the test aircraft must be equipped with some spin-recovery device such as a tail parachute, jettisonable ballast, or some method of rapidly moving the center of gravity forward. Agricultural airplanes are typically certificated in

1513-660: A total of 3,437 I-153s were built. The I-153 first saw combat in 1939 during the Soviet-Japanese Battle of Khalkin Gol in Mongolia . The Japanese Army Air Forces' Type 97 Fighter ( Nakajima Ki-27 ) Nate proved a formidable opponent for the I-15bis and I-16, but was more evenly matched with the I-153, which retained agility inherent to biplanes while having improved performance. While the overall I-153 performance

1602-411: Is composed of opposing roll and yaw. It is crucial that the yaw be countered to effect recovery. The visual field in a typical spin (as opposed to a flat spin) is heavily dominated by the perception of roll over yaw, which can lead to an incorrect and dangerous conclusion that a given inverted spin is actually an erect spin in the reverse yaw direction (leading to a recovery attempt in which pro-spin rudder

1691-554: Is hardest to push") and held (aka the Mueller/Beggs technique). An advantage of the Mueller/Beggs technique is that no knowledge of whether the spin is erect or inverted is required during what can be a very stressful and disorienting time. Even though this method does work in a specific subset of spin-approved airplanes, the NASA Standard/PARE procedure can also be effective provided that care must be taken to ensure

1780-417: Is mistakenly applied and then further exacerbated by holding the incorrect elevator input). In some aircraft that spin readily upright and inverted, such as Pitts- and Christen Eagle-type high-performance aerobatic aircraft, an alternative spin-recovery technique may effect recovery as well, namely: Power off, Hands off the stick/yoke, Rudder full opposite to the spin (or more simply "push the rudder pedal that

1869-401: Is still typically reduced to idle thrust and pitch control neutralized, opposite rudder is almost never used. Adverse yaw created by the rolling surfaces (ailerons, differential horizontal tails, etc.) of such aircraft is often more effective in arresting the spin rotation than the rudder(s), which usually become blanked by the wing and fuselage due to the geometric arrangement of fighters. Hence,

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1958-652: Is the Piper Tomahawk , which is certified for spins, though the Piper Tomahawk's spin characteristics remain controversial. Aircraft that are not certified for spins may be difficult or impossible to recover once the spin exceeds the one-turn certification standard. Though spinning has been removed from most flight training courses, some countries still require flight training on spin recovery. The U.S. requires spin training for civilian flight instructor candidates and military pilots. A spin occurs only after

2047-413: Is typical of an aircraft with moderate or high aspect ratio and little or no sweepback which leads to spin motion which is primarily rolling with moderate yaw. For a low aspect ratio swept wing with relatively large yaw and pitch inertia the diagram will be different and illustrates a predominance of yaw. One common scenario that can lead to an unintentional spin is a skidding uncoordinated turn toward

2136-703: The Battle of Wuhan , the Battle of South Guangxi , the Battle of Chongqing-Chengdu , etc. The tough biplane was quite clearly outmatched during the debut dogfight against the new Mitsubishi A6M Zero fighter over Chongqing on 13 September 1940, although I-15bis pilots Maj. Zheng Shaoyu , Lt. Gao Youxin , and Lt. Xu Jixiang were able to target and damage some of the Zeroes, with Lt. Gao believing he had shot one down (all Zeroes returned to base in Wuhan , with four Zeroes suffering some damage); all three of those pilots survived

2225-586: The Curtiss F11C Goshawk . The first batch of 25 Polikarpovs arrived in Cartagena , Spain, on 28 October 1936, with 15 pilots, led by future ace Pavel Rychagov . A few days later a further group of 10 pilots and 15 aircraft arrived in Bilbao . The Soviet pilots first went into action 4 November, when I-15s shot down two Junkers Ju 52 /3ms and two CR.32s over Madrid, and forced a third Ju 52 and

2314-604: The Fiat CR.32 biplanes used by the Italian forces supporting the Nationalists, which suggested a need to continue the use of biplane fighters, and as a result, Polikarpov's proposals were accepted, and his design bureau was instructed to design a new biplane fighter. Polikarpov assigned the task to the design team led by Aleksei Ya Shcherbakov , who was assisted by Artem Mikoyan and Mikhail Gurevich (who would later set up

2403-822: The Fiat CR.32 . By 1 January 1939, 197 Polikarpovs had been lost: 88 shot down by enemy aircraft and nine by anti-aircraft artillery, 27 destroyed on the ground and 67 written off in accidents. More than 1,000 I-15bis fighters were still in Soviet use during the German invasion when the biplane was employed in the ground attack role. Many were destroyed in the opening hours of the invasion sitting in neat rows on their runways. By November 1943, all examples still in service had been relegated to second line duties. Data from Of Chaika and Chato… General characteristics Performance Armament Related development Aircraft of comparable role, configuration, and era Related lists The initial version of this article

2492-602: The MiG design bureau). The new fighter (designated I-15ter by the design bureau and I-153 by the Soviet Air Forces (VVS)) was based closely on the design of the I-15bis, with a stronger structure, but was fitted with a manually retractable undercarriage to reduce drag. It reverted to the "gulled" upper wing of the original I-15 but used the Clark YH aerofoil of the I-15bis. The four 7.62 mm PV-1 machine guns of

2581-584: The Mongolian People's Army Air Force in mid-July 1939 and flight personnel were trained for rear air defence. Afterwards, they received more than 30 aircraft in March 1942. The I-15 was used extensively in combat by the Republicans in the Spanish Civil War and proved to be one of the best fighter biplanes of its time. The Nationalists called the fighter "Curtiss", apparently believing it to be

2670-425: The Polikarpov I-16 had gained notoriety for entering spins, pilots found it easy to recover from a spin. In contrast, while the I-153 was difficult to spin, once it lost control, recovery was difficult to the point where intentional spinning was forbidden for some time. A spin recovery procedure was eventually developed but, while effective, it required flawless timing and execution. By the end of production in 1941,

2759-484: The aircraft has sufficient yaw while at the stall point. In a normal spin, the wing on the inside of the turn stalls while the outside wing remains flying. It is possible for both wings to stall, but the angle of attack of each wing, and consequently its lift and drag , are different. Either situation causes the aircraft to autorotate toward the stalled wing due to its higher drag and loss of lift. Spins are characterized by high angle of attack, an airspeed below

Polikarpov I-153 - Misplaced Pages Continue

2848-638: The 14th fighter for the VVS , the I-14, started as an advanced (for the era) monoplane under the direction of Andrei Tupolev . He grew concerned that the design would not mature, and ordered two backup biplane designs as the I-14A and B just to be safe. Polikarpov had just been released from prison in August 1932, and was handed the I-14A project. When both the I-14 and I-14A were ordered into production, Polikarpov's design,

2937-408: The 1970s and '80s, and repeatedly recommended by the FAA and implemented by the majority of test pilots during certification spin-testing of light airplanes. Inverted spinning and erect or upright spinning are dynamically very similar and require essentially the same recovery process but use opposite elevator control. In an upright spin, both roll and yaw are in the same direction, but an inverted spin

3026-634: The Gosport School of Special Flying, while in France, at the School of Acrobacy and Combat, Americans who had volunteered to serve in the famous Lafayette Escadrille were by July 1917 learning how to do what the French called a vrille . During the 1920s and 1930s, before night-flying instruments were commonly available on small aircraft, pilots were often instructed to enter a spin deliberately to avoid

3115-570: The I-15bis were replaced by four ShKAS machine guns . While still rifle-calibre weapons, these fired much faster than the PV-1s, (1,800 rounds per minute rather than 750 rounds per minute) giving a much greater weight of fire. The new fighter was to be powered by a Shvetsov M-62 an improved derivative of the Shvetsov M-25 that powered the I-15 and I-15bis with twin superchargers . The aircraft

3204-597: The M-62, which were non-geared. The reason is that AZsh-62IR is just a version of M-62, with absolute equality in all instead of a frontal gearbox and weapon synchronizer absence. Also, none of original engines from recovered wrecks could have been brought to life. Data from Of Chaika and Chato...Polikarpov's Fighting Biplanes" General characteristics Performance Armament Aircraft of comparable role, configuration, and era Related lists Polikarpov I-15 The Polikarpov I-15 ( Russian : И-15 )

3293-539: The P-39 and were able to demonstrate its dangerous spinning characteristics. Modern fighter aircraft are not immune to the phenomenon of unrecoverable spin characteristics. Another example of a nonrecoverable spin occurred in 1963, with Chuck Yeager at the controls of the NF-104A rocket-jet hybrid: during his fourth attempt at setting an altitude record, Yeager lost control and entered a spin, then ejected and survived. On

3382-537: The Pitts S-1 designated the Sunbird S-1x. Suderman started from an altitude of 24,500 ft (7,500 m) and recovered at 2,000 ft (610 m). For safety, all certificated, single-engine fixed-wing aircraft , including certificated gliders , must meet specified criteria regarding stall and spin behavior. Complying designs typically have a wing with greater angle of attack at the wing root than at

3471-573: The Soviet Union and a further 287 under license by CASA in Spain. The gulled upper wing of the I-15 was unpopular with some pilots, as it was felt to restrict visibility, so Polikarpov's design bureau produced a revised version, again powered by the M-25, with a longer span un-gulled upper wing. This version, the I-15bis, commenced production in 1937, a total of 2,408 I-15bis' being delivered by

3560-519: The U.S. demonstration of spin entry and recovery is still expected of glider instructor certification. Also, before their initial certifications both airplane and glider instructors need a logbook endorsement of proficiency in spin training which, under Federal Aviation Regulations 61.183(i), may be given by another instructor. In Canada, spins are a mandatory exercise to get the private and commercial pilot licenses; Canadian recreational pilot permit candidates (1 level below private pilot license) must do

3649-410: The aft limit at which spins may be attempted is not as far aft as the aft limit for general flying. Intentional spinning should not be attempted casually, and the most important pre-flight precaution is to determine that the airplane's center of gravity is within the range approved for intentional spinning. For this reason, pilots should first determine what tendency the airplane has before it stalls. If

Polikarpov I-153 - Misplaced Pages Continue

3738-540: The aircraft entering production concurrently with ongoing testing and development. Early production I-153s powered by the M25 engine passed state testing during 1939, despite the loss of one aircraft which disintegrated in a 500 km/h (311 mph) dive. In test flights, the I-153 (M-25) achieved the top speed of 424 km/h (264 mph), service ceiling of 8,700 m (28,500 ft), and required 6 minutes 24 seconds to reach 5,000 m (16,404 ft). This performance

3827-436: The aircraft now under control, Parke climbed, made another approach, and landed safely. In spite of the discovery of "Parke's technique", spin-recovery procedures were not a routine part of pilot training until well into World War I. The first documented case of an intentional spin and recovery is that of Harry Hawker . In the summer of 1914, Hawker recovered from an intentional spin over Brooklands , England, by centralizing

3916-644: The aircraft to stall. This is called a cross-control stall , and is very dangerous if it happens at low altitude where the pilot has little time to recover. To avoid this scenario, pilots learn the importance of always making coordinated turns. They may simply choose to make the final turn earlier and shallower to prevent an overshoot of the runway center line and provide a larger margin of safety. Certificated, light, single-engine airplanes must meet specific criteria regarding stall and spin behavior. Spins are often entered intentionally for training, flight testing, or aerobatics. In aircraft that are capable of recovering from

4005-468: The aircraft was already in production. Desperate to improve performance, Polikarpov tested two I-153 with the Shvetsov M-63 engine with 820 kW (1,100 hp). However, the results were disappointing and it was becoming painfully obvious that the biplane airframe was incapable of higher speeds. One of the rarely mentioned characteristics of the I-153 was its poor performance in a spin . While

4094-479: The airflow on the wing. During the 1970s, NASA used its spin tunnel at the Langley Research Center to investigate the spinning characteristics of single-engine general aviation airplane designs. A 1/11-scale model was used with nine different tail designs. Some tail designs that caused inappropriate spin characteristics had two stable spin modes—one steep or moderately steep; and another that

4183-429: The airplane returned to level flight. This procedure is sometimes called PARE , for P ower idle, A ilerons neutral, R udder opposite the spin and held, and E levator through neutral. The mnemonic "PARE" simply reinforces the tried-and-true NASA standard spin recovery actions—the very same actions first prescribed by NACA in 1936, verified by NASA during an intensive, decade-long spin test program overlapping

4272-504: The angle of attack is reduced at the outboard regions of both wings. This necessitates an increase in angle of attack at the inboard (center) regions of the wing, and promotes stalling of the inboard regions well before the wing tips. A US certification standard for civil airplanes up to 12,500 lb (5,700 kg) maximum takeoff weight is Part 23 of the Federal Aviation Regulations , applicable to airplanes in

4361-559: The area were 14 aircraft of 70th IAP. Their number increased in the following weeks: on 23 May, 35 I-15bis from 22nd IAP arrived from the Trans-Baikal region. However the Mongolian Polikarpov pilots had been hastily trained and they suffered heavy losses against the more experienced Japanese pilots. During this conflict, the Soviet Union, Mongolia and Japan lost more than 200 aircraft each. 10 aircraft were delivered to

4450-477: The armament. The I-153 series underwent trials with two synchronized 12.7 mm (0.5 in) TKB-150 (later designated Berezin BS ) machine guns, and about 150 aircraft were built with a single TKB-150 in the fuselage and two ShKAS in the wings (a single TKB-150 was used because of the shortage of this weapon which was shared with I-16 Type 29). Late in production, about 400 aircraft were modified with metal plates under

4539-654: The battle. Pilot Captain Shen Tse-Liu is credited with 4 victories in his I-15bis, the most with the aircraft in the war. In 1939 Polikarpov fighters were extensively used during the Battles of Khalkhin Gol fought around the Khalkha River in Dornod Province . The battles were fought during 11 May–16 September 1939, and involved more than 600 planes. When hostilities commenced, the only I-15bis in

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4628-513: The controls. Russian aviator Konstantin Artseulov , having independently discovered a recovery technique, somewhat different from Parke's and Hawker's, on the frontlines, demonstrated it in a dramatic display over the Kacha flight school 's airfield on September 24, 1916, intentionally flying his Nieuport 21 into a spin and recovering from it twice. Later, Artseulov, at the time an instructor at

4717-421: The elevator control is moved briskly forward to reduce the angle of attack below the critical angle . Depending on the airplane and type of spin, the elevator action could be a minimal input before rotation ceases, or in other cases the pilot may have to move the elevator control to its full forward position to effect recovery from the upright spin. Once the rotation has stopped, the rudder must be neutralized and

4806-422: The entry phase and then experience normal gravity, except that the extreme nose-down attitude presses the occupants forward against their restraint harnesses. The rapid rotation, combined with the nose-down attitude, results in a visual effect called ground flow that can be disorienting. The recovery procedure from a spin requires using rudder to stop the rotation, then elevator to reduce angle of attack to stop

4895-421: The further forward the center of gravity the less readily the airplane will spin, and the more readily it can recover from a spin. Conversely, the further aft the center of gravity the more readily the airplane will spin, and the less readily it can recover from a spin. In any airplane, the forward and aft limits on center of gravity are carefully defined. In some airplanes that are approved for intentional spinning,

4984-532: The mainwheels retracting rearwards, rotating through 90 degrees to lie flat in the wing roots, being actuated by cables operated by a pilot-driven handwheel. The solid rubber tailwheel did not retract, but moved in conjunction with the rudder. The M-62 was not ready by the time the first prototype was complete, so it was fitted with a 750 hp (560 kW) M-25V engine when it made its maiden flight in August 1938. The first prototype failed factory testing due to numerous defects, but this did not stop production, with

5073-641: The much more dangerous graveyard spiral when they suddenly found themselves enveloped in clouds, hence losing visual reference to the ground. In almost every circumstance, the cloud deck ends above ground level, giving the pilot a reasonable chance to recover from the spin before crashing. Today, spin training is not required for a private pilot licence in the United States; added to this, most training-type aircraft are placarded "intentional spins prohibited". Some models of Cessna 172 are certified for spinning although they can be difficult to actually get into

5162-420: The normal category at a moderate weight. For single-engine airplanes this requires successful demonstration of the one-turn spin. However, with the agriculture hopper full these airplanes are not intended to be spun, and recovery is unlikely. For this reason, at weights above the maximum for the normal category, these airplanes are not subjected to spin testing and, as a consequence, can only be type certificated in

5251-524: The normal, utility and acrobatic categories. Part 23, §23.221 requires that single-engine airplanes must demonstrate recovery from either a one-turn spin if intentional spins are prohibited or six-turn spins if intentional spins are approved. Even large, passenger-carrying single-engine airplanes like the Cessna Caravan must be subjected to one-turn spins by a test pilot and repeatedly demonstrated to recover within no more than one additional turn. With

5340-434: The nose above the horizon. Such maneuvers must be performed with the center of gravity in the normal range and with appropriate training, and consideration should be given to the extreme gyroscopic forces generated by the propeller and exerted on the crankshaft. Guinness World Records lists the highest number of consecutive inverted flat spins at 98, set by Spencer Suderman on March 20, 2016, flying an experimental variant of

5429-511: The other hand, the Cornfield Bomber was a case where the ejection of the pilot shifted the center of gravity enough to let the now-empty aircraft self-recover from a spin and land itself. In purpose-built aerobatic aircraft, spins may be intentionally flattened through the application of power and aileron within a normal spin. Rotation rates experienced are dramatic and can exceed 400 degrees per second in an attitude that may even have

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5518-475: The other. The wing that stalls first drops, increasing its angle of attack and deepening the stall. At least one wing must be stalled for a spin to occur. The other wing rises, decreasing its angle of attack, and the aircraft yaws towards the more deeply stalled wing. The difference in lift between the two wings causes the aircraft to roll, and the difference in drag causes the aircraft to continue yawing. The spin characteristics diagram shown in this section

5607-442: The pilot's inputs to the flight controls, and recovery from a spiral dive requires a different set of actions from those required to recover from a spin. In the early years of flight, a spin was frequently referred to as a "tailspin". Many types of airplanes spin only if the pilot simultaneously yaws and stalls the airplane (intentionally or unintentionally). Under these circumstances, one wing stalls, or stalls more deeply than

5696-428: The preferred recover technique has a pilot applying full roll control in the direction of the rotation ( i.e. , a right-hand spin requires a right stick input), generally remembered as "stick into the spin". Likewise, this control application is reversed for inverted spins. The characteristics of an airplane with respect to spinning are significantly influenced by the position of the center of gravity . In general terms,

5785-473: The restricted category. As an example of an agricultural airplane, see the Cessna AG series . To make some sailplanes spin easily for training purposes or demonstrations, a spin kit is available from the manufacturer. Many training aircraft may appear resistant to entering a spin, even though some are intentionally designed and certified for spins. A well-known example of an aircraft designed to spin readily

5874-407: The rudder (i.e., a cross-control). If the aircraft manufacturer provides a specific procedure for spin recovery, that procedure must be used. Otherwise, to recover from an upright spin, the following generic procedure may be used: Power is first reduced to idle and the ailerons are neutralized. Then, full opposite rudder (that is, against the yaw) is added and held to counteract the spin rotation, and

5963-591: The runway during the landing sequence. A pilot who is overshooting the turn to final approach may be tempted to apply more rudder to increase the rate of turn. The result is twofold: the nose of the airplane drops below the horizon, and the bank angle increases due to rudder roll. Reacting to these unintended changes, the pilot then begins to pull the elevator control aft (thus increasing the angle of attack and load factor) while applying opposite aileron to decrease bank angle. Taken to its extreme, this can result in an uncoordinated turn with sufficient angle of attack to cause

6052-517: The school, went on to teach this technique to all of his students, quickly disseminating it among the Russian aviators and beyond. In 1917, the English physicist Frederick Lindemann conducted a series of experiments in a B.E.2E that led to the first understanding of the aerodynamics of the spin. In Britain, starting in 1917, spin recovery procedures were routinely taught by flight instructors at

6141-450: The slots are located ahead of the ailerons, they provide strong resistance to stalling and may even leave the airplane incapable of spinning. The flight control systems of some gliders and recreational aircraft are designed so that when the pilot moves the elevator control close to its fully aft position, as in low speed flight and flight at high angle of attack , the trailing edges of both ailerons are automatically raised slightly so that

6230-417: The spin does not simply cross from positive to negative (or vice versa) and that a too-rapid application of elevator control is avoided as it may cause aerodynamic blanketing of the rudder rendering the control ineffective and simply accelerate the spin. The converse, however, may not be true at all—many cases exist where Beggs/Mueller fails to recover the airplane from the spin, but NASA Standard/PARE terminates

6319-445: The spin. Before spinning any aircraft, a pilot should consult the flight manual to establish if the particular aircraft type has any specific spin recovery techniques that differ from standard practice. A pilot can induce a flat spin once the spin is established by applying full opposite aileron to the direction of rotation—hence, the requirement to neutralize ailerons in the normal spin recovery technique. The aileron application creates

6408-414: The stall on at least one wing and a shallow descent. Recovery and avoiding a crash may require a specific and counter-intuitive set of actions. A spin differs from a spiral dive , in which neither wing is stalled and which is characterized by a low angle of attack and high airspeed. A spiral dive is not a type of spin because neither wing is stalled. In a spiral dive, the aircraft responds conventionally to

6497-408: The stick, and turning into the spin, with no effect. The aircraft descended 450 feet (140 m), and horrified observers expected a fatal crash. Though disabled by centrifugal forces, Parke still sought an escape. In an effort to neutralize the forces pinning him against the right side of the cockpit, he applied full right rudder, and the aircraft leveled out 50 feet (15 m) above the ground. With

6586-525: The tail stall and so rudder input is ineffective to slow/stop rotation. Recovery is initiated by maintaining pro-spin elevator and rudder and applying full aileron into the spin. Differential drag now lowers the nose returning the plane to a normal spin from which the PARE technique is used to exit the maneuver. Although entry techniques are similar, modern military fighter aircraft often tend to require yet another variation on spin recovery techniques. While power

6675-412: The tendency is to pitch down (nose-heavy) when it stalls, then the aircraft is likely to recover on its own. However, if the tendency is to pitch up (tail-heavy) when it stalls, the aircraft will likely transition into a flat spin where stall recovery would be delayed, or it may not be recoverable at all. Before practicing spins, one recommended method is to determine the aircraft's stall tendency by doing

6764-625: The time production finished in 1940. In August 1937, the Chinese Kuomintang Government signed a non-aggression pact with the USSR, and in autumn of the same year, the Soviet Union commenced to ship I-15s as a part of a programme of military aid to the Chinese Air Force (CAF) in its defensive war against Japan. More than 250 Soviet pilots volunteered to fly the 255 I-15s supplied to China in autumn 1937. By 1939,

6853-586: The total number of Polikarpov biplanes delivered to CAF reached 347 I-15/I-15bis. The I-15bis also saw a great amount of action in the Soviet–Japanese border conflicts along the China–Mongolia border . From 1938 to 1941, I-15s in the Nationalist Air Force of China , fought many major battles, and skirmishes against invading and occupying Japanese forces, including the Battle of Taierzhuang ,

6942-675: The two-speed supercharger . The Polikarpov I-153 Chaika never flew with any Spanish Air Force units during or after the Spanish Civil War. Two earlier variants of this aircraft, the I-15 and the I-15bis, did fly with the Republican Air Force during the conflict and, later, captured examples of both types were used by the Fuerzas Aéreas till the early 1950s. While attempts to improve performance proved largely fruitless, Polikarpov had some success in upgrading

7031-419: The type and model of aircraft being flown but there are general procedures applicable to most aircraft. These include reducing power to idle and simultaneously raising the nose to induce an upright stall. Then, as the aircraft approaches stall, apply full rudder in the desired spin direction while holding full back-elevator pressure for an upright spin. Sometimes a roll input is applied in the direction opposite of

7120-520: The wing tip, so that the wing root stalls first, reducing the severity of the wing drop at the stall and possibly also allowing the ailerons to remain somewhat effective until the stall migrates outward toward the wing tip. One method of tailoring such stall behavior is known as washout . Some designers of recreational aircraft seek to develop an aircraft that is characteristically incapable of spinning, even in an uncoordinated stall . Some airplanes have been designed with fixed leading edge slots . Where

7209-552: The wings to accommodate RS-82 unguided rockets. Other variants included: There are four complete survivors of this plane, three of which can fly. In the early 1990s, New Zealand pilot and entrepreneur Tim Wallis ' Alpine Fighter Collection organised the restoration of three I-153s and six I-16s to an airworthy condition, this project being completed in 1999 as the third and final I-153 arrived in New Zealand. These aircraft were equipped with AZsh-62IR geared radials instead of

7298-544: Was a Soviet biplane fighter aircraft of the 1930s. Nicknamed Chaika ( Russian : Чайка , "Seagull") because of its gulled upper wings, it was operated in large numbers by the Soviet Air Force, and together with the Polikarpov I-16 monoplane, was one of the standard fighters of the Spanish Republicans during the Spanish Civil War , where it was called Chato (snub-nose). The design for

7387-451: Was able to exit spins at will, according to Harry Bruno in Wings over America (1944). In August 1912, Lieutenant Wilfred Parke RN became the first aviator to recover from an accidental spin when his Avro Type G biplane entered a spin at 700 feet (210 m) AGL in the traffic pattern at Larkhill . Parke attempted to recover from the spin by increasing engine speed, pulling back on

7476-494: Was based on material from aviation.ru . It has been released under the GFDL by the copyright holder. Spin (flight) In flight dynamics a spin is a special category of stall resulting in autorotation (uncommanded roll) about the aircraft's longitudinal axis and a shallow, rotating, downward path approximately centred on a vertical axis. Spins can be entered intentionally or unintentionally, from any flight attitude if

7565-444: Was either moderately flat or flat. Recovery from the flatter of the two modes was usually less reliable or impossible. When the center of gravity was further aft, the spin was flatter and the recovery was less reliable. For all tests, the center of gravity of the model was at either 14.5% of mean aerodynamic chord (MAC) or 25.5% of MAC. Single-engine airplane types certified in the normal category must be demonstrated to recover from

7654-410: Was of mixed metal and wood construction, with the fuselage structure being based on chromium - molybdenum steel with duralumin skinning on the forward fuselage, and fabric covering on the fuselage aft of the front of the cockpit. The aircraft's wings were made of fabric covered wood, while the tail surfaces were of fabric covered duralumin. The aircraft was fitted with a tailwheel undercarriage , with

7743-435: Was satisfactory, some significant problems were revealed. Most troublesome was the absence of a firewall between the fuel tank mounted in front of the cockpit and the pilot. Combined with strong draft coming in through the wheel wells, fuel tank fires invariably resulted in rapid engulfment of the cockpit and severe burns to the pilot. In addition, the M-62 engine suffered from a service life of only 60–80 hours due to failures of

7832-507: Was undergoing repair. In December 1936 and January 1937, two more shipments of 30 aircraft arrived in Spain, making it possible to form four full-strength I-15 squadrons. Until the spring of 1937, central Spain was the main war theatre for I-15s. And in May 1937, another batch of 31 Polikarpov landed in Spain, taking the total number of I-15s delivered to 116. Chato losses in the Spanish Civil War were comparable to those of its principal rival,

7921-416: Was well in excess of that demonstrated by the I-15bis. During 1939, production switched to a version powered by the originally planned M-62 engine, with an M-62 powered prototype undergoing state testing from 16 June 1939. While speed at sea level was virtually unchanged, the new engine improved performance at altitude. A speed of 443 km/h (275 mph) at 4,600 m (15,100 ft) was recorded, with

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