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Soviet Heavy Tank KV-1. 1942
Image by Peer.Gynt
The Kliment Voroshilov (KV) tanks were a series of Soviet heavy tanks, named after the Soviet defense commissar and politician Kliment Voroshilov. The KV series were known for their extremely heavy armour protection during the early war, especially during the first year of the invasion of the Soviet Union in World War II. Almost completely immune to the 3.7 cm KwK 36 and howitzer-like, short barreled 7.5 cm KwK 37 guns mounted respectively on the early Panzer III and Panzer IV tanks, until better guns were developed often the only way to defeat a KV was a point-blank shot to the rear. Prior to the invasion, about 500 of the over 22,000 tanks in Soviet service at the time were of the KV-1 type. When the KV-1 appeared, it outclassed the French Char B1, the only heavy tank used in the world at that time. Yet in the end it turned out that there was little sense in producing the expensive KV tanks, as the T-34 medium tank performed better (or at least equally) in all practical respects. Later in the war, the KV series became a base of development of the Iosif Stalin tanks.
Development
After disappointing results with the multi-turreted T-35 heavy tank, Soviet tank designers started drawing up replacements. The T-35 conformed to the 1920s notion of a ‘breakthrough tank’ with very heavy firepower and armour protection, but suffered from poor mobility. The Spanish Civil War demonstrated the need for much heavier armor on tanks, and was the main influence on Soviet tank design just prior to World War II.
Several competing designs were offered, and even more were drawn up prior to reaching prototype stage. All had heavy armour, torsion-bar suspension, wide tracks, and were of welded and cast construction. One of the main competing designs was the SMK, which in its final form had two turrets, mounting the same combination of 76.2 mm and 45 mm weapons. The designers of the SMK independently drew up a single-turreted variant and this received approval at the highest level. Two of these, named after the People’s Defence Commissioner were ordered alongside a single SMK. The smaller hull and single turret enabled the designer to install heavy frontal and turret armour while keeping the weight within manageable limits.
When the Soviets entered the Winter War, the SMK, KV and a third design, the T-100, were sent to be tested in combat conditions. The KV outperformed the SMK and T-100 designs. The KV’s heavy armour proved highly resistant to Finnish anti-tank weapons, making it more difficult to stop. In 1939 production of 50 KV was ordered. During the War, the Soviets found it difficult to deal with the concrete bunkers used by the Finns and a request was made for a tank with a large howitzer. One of the rush projects to meet the request put the howitzer in a new turret on one of the KV tanks.
Initially known as Little Turret and Big turret, the 76-mm-armed tank was designated as the KV-1 Heavy Tank and the 152 mm howitzer one as KV-2 Heavy Artillery Tank.
The KV’s strengths included armor that was impenetrable by any tank-mounted weapon then in service except at point-blank range, that it had good firepower, and that it had good traction on soft ground. It also had serious flaws: it was difficult to steer, the transmission (which was a twenty year old Caterpillar design) was unreliable (and was known to have to be shifted with a hammer),[6] and the ergonomics were poor, with limited visibility and no turret basket. Furthermore, at 45 tons, it was simply too heavy. This severely impacted the maneuverability, not so much in terms of maximum speed, as through inability to cross many bridges medium tanks could cross. The KV outweighed most other tanks of the era, being about twice as heavy as the heaviest contemporary German tank. KVs were never equipped with a snorkeling system to ford shallow rivers, so they had to be left to travel to an adequate bridge. As applique armor and other improvements were added without increasing engine power, later models were less capable of keeping up to speed with medium tanks and had more trouble with difficult terrain. In addition, its firepower was no better than the T-34. It took field reports from senior commanders "and certified heroes", who could be honest without risk of punishment, to reveal "what a dog the KV-1.
By 1942, when the Germans were fielding large numbers of long-barrelled 50 mm and 75 mm guns, the KV’s armor was no longer invincible. The KV-1’s side, top, and turret armor could also be penetrated by the high-velocity MK 101 carried by German ground attack aircraft such as the Henschel Hs 129, requiring the installation of additional field-expedient appliqué armour. The KV-1’s 76.2 mm gun also came in for criticism. While adequate against all German tanks, it was the same gun as carried by smaller, faster, and cheaper T-34 medium tanks. In 1943, it was determined that this gun could not penetrate the frontal armour of the new Tiger,the first German heavy tank, fortunately captured near Leningrad. The KV-1 was also much more difficult to manufacture and thus more expensive than the T-34. In short, its advantages no longer outweighed its drawbacks.
Nonetheless, because of its initial superior performance, the KV-1 was chosen as one of the few tanks to continue being built following the Soviet reorganization of tank production. Due to the new standardization, it shared the similar engine (the KV used a 600 hp V-2K modification of the T-34’s V-2 diesel engine) and gun (the KV had a ZiS-5 main gun, while the T-34 had a similar F-34 main gun) as the T-34, was built in large quantities, and received frequent upgrades.
When production shifted to the Ural Mountains ‘Tankograd’ complex, the KV-2 was dropped. While impressive on paper, it had been designed as a slow-moving bunker-buster. It was less useful in highly mobile, fluid warfare that developed in World War II. The turret was so heavy it was difficult to traverse on non-level terrain, and it was expensive to produce. Only about 300 KV-2s were made, all in 1940-41, making it one of the rarer Soviet tanks. Many KV-2s were later converted into KV-1s.
As the war continued, the KV-1 continued to get more armour to compensate for the increasing effectiveness of German weapons. This culminated in the KV-1 model 1942 (German designation KV-1C), which had very heavy armour, but lacked a corresponding improvement to the engine. Tankers complained that although they were well-protected, their mobility was poor and they had no firepower advantage over the T-34 medium tank.[citation needed]
In response to criticisms, the lighter KV-1S (Russian language: КВ-1С) was released, with thinner armour and a smaller, lower turret in order to reclaim some speed. Importantly, the KV-1S also had a commander’s cupola with all-around vision blocks, a first for a Soviet heavy tank. However, the thinning-out of the armor called into question why the tank was being produced at all, when the T-34 could seemingly do everything the KV could do and much more cheaply. The Soviet heavy tank program was close to cancellation in mid-1943.
The appearance of the German Panther tank in the summer of 1943 convinced the Red Army to make a serious upgrade of its tank force for the first time since 1941. Soviet tanks needed bigger guns to take on the growing numbers of Panthers and the few Tigers.
A stopgap upgrade to the KV series was the short-lived KV-85 or Objekt 239. This was a KV-1S with a new turret designed for the IS-85, mounting the same 85 mm D-5T gun as the SU-85 and early versions of the T-34-85; demand for the gun slowed production of the KV-85 tremendously and only 148 were built before the KV design was replaced. The KV-85 was produced in the fall and winter of 1943-44; they were sent to the front as of September 1943 and production of the KV-85 was stopped by the spring of 1944 once the IS-2 entered full scale production.
Successor
A new heavy tank design entered production late in 1943 based on the work done on the KV-13. Because Kliment Voroshilov had fallen out of political favour, the new heavy tank series was named the Iosif Stalin tank, after Iosif (Joseph) Stalin. The KV-13 program’s IS-85 prototype was accepted for production as the IS-1 (or IS-85, Object 237) heavy tank. After testing with both 100 mm and 122 mm guns, the D-25T 122 mm gun was selected as the main armament of the new tank, primarily because of its ready availability and the effect of its large high-explosive shell when attacking German fortifications. The 122mm D-25T used a separate shell and powder charge, resulting in a lower rate of fire and reduced ammunition capacity. While the 122mm armour piercing shell had a lower muzzle velocity than similar late German 7.5 cm and 8.8 cm guns, proving-ground tests showed that the 122mm AP shell could defeat the frontal armour of the German Panther tank, and the HE shell would easily blow off the drive sprocket and tread of the heaviest German tank or self-propelled gun. The IS-122 replaced the IS-85, and began mass production as the IS-2. The 85 mm gun saw service in the lighter SU-85 and T-34-85.
A destroyed Soviet KV-1 in Olonets, September 1941, during the Continuation War
Some KVs remained in service right up to the end of the war, although in greatly diminishing numbers as they wore out or were knocked out. The 260th Guards Heavy Breakthrough Tank Regiment, based on the Leningrad front, operated a number of 1941-vintage KV-1s at least as late as the summer of 1944 before re-equipping with IS-2s. A regiment of KVs saw service in Manchuria in August 1945, and a few KV-85s were used in the Crimea in the summer of 1944. The Finnish forces had two KVs, nicknamed Klimi, a Model 1940 and Model 1941, both of which received minor upgrades in their service, and both of which survived the war. A single captured KV-2 was used by German forces in 1945 against US forces in the Ruhr.
Specifications (KV-1 Model 1941)
Weight – 45 tonnes
Length – 6.75 m (22 ft 2 in)
Width – 3.32 m (10 ft 11 in)
Height -2.71 m (8 ft 11 in)
Crew – 5
Armour – 90 mm maximum
Main armament -76.2 mm model F-34 gun
Secondary armament – 3× or 4× DT machine guns
Engine – 12-cylinder diesel model V-2 600 hp (450 kW)
Power/weight – 13 hp/tonne
Suspension – Torsion bar
Operational range – 335 km
Speed – 35 km/h (22 mph)
Steven F. Udvar-Hazy Center: Boeing 367-80 (prototype 707, first jet airliner), and De Havilland Canada DHC-1A Chipmunk Pennzoil Special
Image by Chris Devers
Quoting Smithsonian National Air and Space Museum | De Havilland-Canada DHC-1A Chipmunk, Pennzoil Special:
De Havilland originally designed the Chipmunk after World War II as a primary trainer to replace the venerable Tiger Moth. Among the tens of thousands of pilots who trained in or flew the Chipmunk for pleasure was veteran aerobatic and movie pilot Art Scholl. He flew his Pennzoil Special at air shows throughout the 1970s and early ’80s, thrilling audiences with his skill and showmanship and proving that the design was a top-notch aerobatic aircraft.
Art Scholl purchased the DHC-1A in 1968. He modified it to a single-seat airplane with a shorter wingspan and larger vertical fin and rudder, and made other changes to improve its performance. Scholl was a three-time member of the U.S. Aerobatic Team, an air racer, and a movie and television stunt pilot. At air shows, he often flew with his dog Aileron on his shoulder or taxied with him standing on the wing.
Gift of the Estate of Arthur E. Scholl
Manufacturer:
De Havilland Canada Ltd.
Pilot:
Art Scholl
Date:
1946
Country of Origin:
United States of America
Dimensions:
Wingspan: 9.4 m (31 ft)
Length: 7.9 m (26 ft)
Height: 2.1 m (7 ft 1 in)
Weight, empty: 717 kg (1,583 lb)
Weight, gross: 906 kg (2,000 lb)
Top speed: 265 km/h (165 mph)
Engine: Lycoming GO-435, 260 hp
Materials:
Overall: Aluminum Monocoque Physical Description:Single-engine monoplane. Lycoming GO-435, 260 hp engine.
• • • • •
Quoting Smithsonian National Air and Space Museum | Boeing 367-80 Jet Transport:
On July 15, 1954, a graceful, swept-winged aircraft, bedecked in brown and yellow paint and powered by four revolutionary new engines first took to the sky above Seattle. Built by the Boeing Aircraft Company, the 367-80, better known as the Dash 80, would come to revolutionize commercial air transportation when its developed version entered service as the famous Boeing 707, America’s first jet airliner.
In the early 1950s, Boeing had begun to study the possibility of creating a jet-powered military transport and tanker to complement the new generation of Boeing jet bombers entering service with the U.S. Air Force. When the Air Force showed no interest, Boeing invested million of its own capital to build a prototype jet transport in a daring gamble that the airlines and the Air Force would buy it once the aircraft had flown and proven itself. As Boeing had done with the B-17, it risked the company on one roll of the dice and won.
Boeing engineers had initially based the jet transport on studies of improved designs of the Model 367, better known to the public as the C-97 piston-engined transport and aerial tanker. By the time Boeing progressed to the 80th iteration, the design bore no resemblance to the C-97 but, for security reasons, Boeing decided to let the jet project be known as the 367-80.
Work proceeded quickly after the formal start of the project on May 20, 1952. The 367-80 mated a large cabin based on the dimensions of the C-97 with the 35-degree swept-wing design based on the wings of the B-47 and B-52 but considerably stiffer and incorporating a pronounced dihedral. The wings were mounted low on the fuselage and incorporated high-speed and low-speed ailerons as well as a sophisticated flap and spoiler system. Four Pratt & Whitney JT3 turbojet engines, each producing 10,000 pounds of thrust, were mounted on struts beneath the wings.
Upon the Dash 80’s first flight on July 15, 1954, (the 34th anniversary of the founding of the Boeing Company) Boeing clearly had a winner. Flying 100 miles per hour faster than the de Havilland Comet and significantly larger, the new Boeing had a maximum range of more than 3,500 miles. As hoped, the Air Force bought 29 examples of the design as a tanker/transport after they convinced Boeing to widen the design by 12 inches. Satisfied, the Air Force designated it the KC-135A. A total of 732 KC-135s were built.
Quickly Boeing turned its attention to selling the airline industry on this new jet transport. Clearly the industry was impressed with the capabilities of the prototype 707 but never more so than at the Gold Cup hydroplane races held on Lake Washington in Seattle, in August 1955. During the festivities surrounding this event, Boeing had gathered many airline representatives to enjoy the competition and witness a fly past of the new Dash 80. To the audience’s intense delight and Boeing’s profound shock, test pilot Alvin "Tex" Johnston barrel-rolled the Dash 80 over the lake in full view of thousands of astonished spectators. Johnston vividly displayed the superior strength and performance of this new jet, readily convincing the airline industry to buy this new airliner.
In searching for a market, Boeing found a ready customer in Pan American Airway’s president Juan Trippe. Trippe had been spending much of his time searching for a suitable jet airliner to enable his pioneering company to maintain its leadership in international air travel. Working with Boeing, Trippe overcame Boeing’s resistance to widening the Dash-80 design, now known as the 707, to seat six passengers in each seat row rather than five. Trippe did so by placing an order with Boeing for 20 707s but also ordering 25 of Douglas’s competing DC-8, which had yet to fly but could accommodate six-abreast seating. At Pan Am’s insistence, the 707 was made four inches wider than the Dash 80 so that it could carry 160 passengers six-abreast. The wider fuselage developed for the 707 became the standard design for all of Boeing’s subsequent narrow-body airliners.
Although the British de Havilland D.H. 106 Comet and the Soviet Tupolev Tu-104 entered service earlier, the Boeing 707 and Douglas DC-8 were bigger, faster, had greater range, and were more profitable to fly. In October 1958 Pan American ushered the jet age into the United States when it opened international service with the Boeing 707 in October 1958. National Airlines inaugurated domestic jet service two months later using a 707-120 borrowed from Pan Am. American Airlines flew the first domestic 707 jet service with its own aircraft in January 1959. American set a new speed mark when it opened the first regularly-scheduled transcontinental jet service in 1959. Subsequent nonstop flights between New York and San Francisco took only 5 hours – 3 hours less than by the piston-engine DC-7. The one-way fare, including a surcharge for jet service, was 5.50, or 1 round trip. The flight was almost 40 percent faster and almost 25 percent cheaper than flying by piston-engine airliners. The consequent surge of traffic demand was substantial.
The 707 was originally designed for transcontinental or one-stop transatlantic range. But modified with extra fuel tanks and more efficient turbofan engines, the 707-300 Intercontinental series aircraft could fly nonstop across the Atlantic with full payload under any conditions. Boeing built 855 707s, of which 725 were bought by airlines worldwide.
Having launched the Boeing Company into the commercial jet age, the Dash 80 soldiered on as a highly successful experimental aircraft. Until its retirement in 1972, the Dash 80 tested numerous advanced systems, many of which were incorporated into later generations of jet transports. At one point, the Dash 80 carried three different engine types in its four nacelles. Serving as a test bed for the new 727, the Dash 80 was briefly equipped with a fifth engine mounted on the rear fuselage. Engineers also modified the wing in planform and contour to study the effects of different airfoil shapes. Numerous flap configurations were also fitted including a highly sophisticated system of "blown" flaps which redirected engine exhaust over the flaps to increase lift at low speeds. Fin height and horizontal stabilizer width was later increased and at one point, a special multiple wheel low pressure landing gear was fitted to test the feasibility of operating future heavy military transports from unprepared landing fields.
After a long and distinguished career, the Boeing 367-80 was finally retired and donated to the Smithsonian in 1972. At present, the aircraft is installated at the National Air and Space Museum’s new facility at Washington Dulles International Airport.
Gift of the Boeing Company
Manufacturer:
Boeing Aircraft Co.
Date:
1954
Country of Origin:
United States of America
Dimensions:
Height 19′ 2": Length 73′ 10": Wing Span 129′ 8": Weight 33,279 lbs.
Physical Description:
Prototype Boeing 707; yellow and brown.
Mustang P51 (Jumping Jacques) At Southend Air Show May 2011
Image by Feggy Art
The North American Aviation P-51 Mustang was an American long-range single-seat World War II fighter aircraft conceived, designed and built by North American Aviation (NAA) in response to a specification issued directly to NAA by the British Purchasing Commission; the prototype NA-73X airframe was rolled out, although still minus engine, 102 days after the contract was signed. The first production Mustangs were used by the Royal Air Force (RAF) as tactical-reconnaissance aircraft and fighter-bombers. From late 1943, P-51Bs
(supplemented by P-51Ds from mid-1944) were used by the USAAF’s Eighth Air Force as bomber escorts in raids over Germany, while the RAF’s 2 TAF and the USAAF’s Ninth Air Force used the Merlin-powered Mustangs as fighter-bombers, roles in which the Mustang helped ensure Allied air superiority in 1944. The P-51 was also in service with Allied air forces in the North African, Mediterranean and Italian theatres, and saw limited service against the Japanese in the Pacific War. At the start of Korean War the Mustang was the United Nations’ main fighter but the role was quickly shouldered by jet fighters, including the F-86, after which the Mustang became a specialised ground-attack fighter-bomber. In spite of being superseded by jet fighters the Mustang remained in service with some air forces until the early 1980s.
The Mustang was first designed to use a low-altitude rated Allison V-1710 engine and was mainly used in the tactical-reconnaissance and fighter-bomber roles. The definitive version, the P-51D, was powered by the Packard V-1650-7, a licence-built version of the Rolls-Royce Merlin 60 series two-stage two-speed supercharged engine, and was able to be used as a long-range bomber escort. The P-51D was armed with six .50 caliber (12.7 mm) M2 Browning machine guns.
After World War II and the Korean War, many Mustangs were converted for civilian use, especially air racing. The Mustang’s reputation was such that, in the early 1960s, the Ford Motor Company designed a new youth-oriented coupe which was named after the fighter.
The North American Aviation P-51 Mustang was an American long-range single-seat World War II fighter aircraft conceived, designed and built by North American Aviation (NAA) in response to a specification issued directly to NAA by the British Purchasing Commission; the prototype NA-73X airframe was rolled out, although still minus engine, 102 days after the contract was signed. The first production Mustangs were used by the Royal Air Force (RAF) as tactical-reconnaissance aircraft and fighter-bombers. From late 1943, P-51Bs
(supplemented by P-51Ds from mid-1944) were used by the USAAF’s Eighth Air Force as bomber escorts in raids over Germany, while the RAF’s 2 TAF and the USAAF’s Ninth Air Force used the Merlin-powered Mustangs as fighter-bombers, roles in which the Mustang helped ensure Allied air superiority in 1944. The P-51 was also in service with Allied air forces in the North African, Mediterranean and Italian theatres, and saw limited service against the Japanese in the Pacific War. At the start of Korean War the Mustang was the United Nations’ main fighter but the role was quickly shouldered by jet fighters, including the F-86, after which the Mustang became a specialised ground-attack fighter-bomber. In spite of being superseded by jet fighters the Mustang remained in service with some air forces until the early 1980s.
The Mustang was first designed to use a low-altitude rated Allison V-1710 engine and was mainly used in the tactical-reconnaissance and fighter-bomber roles. The definitive version, the P-51D, was powered by the Packard V-1650-7, a licence-built version of the Rolls-Royce Merlin 60 series two-stage two-speed supercharged engine, and was able to be used as a long-range bomber escort. The P-51D was armed with six .50 calibre (12.7 mm) M2 Browning machine guns.
After World War II and the Korean War, many Mustangs were converted for civilian use, especially air racing. The Mustang’s reputation was such that, in the early 1960s, the Ford Motor Company designed a new youth-oriented coupe which was named after the fighter.
Reproduced from Wikipedia under the GNU Creative Commons License.