Armoured fighting vehicle
An armoured fighting vehicle is an armed combat vehicle protected by armour combining operational mobility with offensive and defensive capabilities. AFVs can be tracked. Main battle tanks, armoured cars, armoured self-propelled guns, armoured personnel carriers are all examples of AFVs. Armoured fighting vehicles are classified according to their intended role on the battlefield and characteristics; the classifications are not absolute. For example lightly armed armoured personnel carriers were superseded by infantry fighting vehicles with much heavier armament in a similar role. Successful designs are adapted to a wide variety of applications. For example, the MOWAG Piranha designed as an APC, has been adapted to fill numerous roles such as a mortar carrier, infantry fighting vehicle, assault gun; the concept of a mobile and protected fighting unit has been around for centuries. Armoured fighting vehicles were not possible until internal combustion engines of sufficient power became available at the start of the 20th century.
Modern armoured fighting vehicles represent the realization of an ancient concept - that of providing troops with mobile protection and firepower. Armies have deployed war cavalries with rudimentary armour in battle for millennia. Use of these animals and engineering designs sought to achieve a balance between the conflicting paradoxical needs of mobility and protection. Siege engines, such as battering rams and siege towers, would be armoured in order to protect their crews from enemy action. Polyidus of Thessaly developed a large movable siege tower, the helepolis, as early as 340 BC, Greek forces used such structures in the Siege of Rhodes; the idea of a protected fighting vehicle has been known since antiquity. Cited is Leonardo da Vinci's 15th-century sketch of a mobile, protected gun-platform; the machine was to be mounted on four wheels which would be turned by the crew through a system of hand cranks and cage gears. Leonardo claimed: "I will build armored wagons which will be invulnerable to enemy attacks.
There will be no obstacle which it cannot overcome." Modern replicas have demonstrated that the human crew would have been able to move it over only short distances. Hussite forces in Bohemia developed war wagons - medieval weapon-platforms - around 1420 during the Hussite Wars; these heavy wagons were given protective sides with firing slits. Heavy arquebuses mounted on wagons were called arquebus à croc; these carried a ball of about 3.5 ounces. The first modern AFVs were armed cars, dating back to the invention of the motor car; the British inventor F. R. Simms designed and built the Motor Scout in 1898, it was the first armed, petrol-engine powered vehicle built. It consisted of a De Dion-Bouton quadricycle with a Maxim machine gun mounted on the front bar. An iron shield offered some protection for the driver from the front, but it lacked all-around protective armour; the armoured car was the first modern armoured fighting vehicle. The first of these was the Simms' Motor War Car, designed by Simms and built by Vickers, Sons & Maxim in 1899.
The vehicle had Vickers armour 6 mm thick and was powered by a four-cylinder 3.3-litre 16 hp Cannstatt Daimler engine giving it a maximum speed of around 9 miles per hour. The armament, consisting of two Maxim guns, was carried in two turrets with 360° traverse. Another early armoured car of the period was the French Charron, Girardot et Voigt 1902, presented at the Salon de l'Automobile et du cycle in Brussels, on 8 March 1902; the vehicle was equipped with a Hotchkiss machine gun, with 7 mm armour for the gunner. Armoured cars were first used in large numbers on both sides during World War I as scouting vehicles. In 1903, H. G. Wells published the short story "The Land Ironclads," positing indomitable war machines that would bring a new age of land warfare, the way steam-powered ironclad warships had ended the age of sail. Wells' literary vision was realized in 1916, amidst the pyrrhic standstill of the Great War, the British Landships Committee, deployed revolutionary armoured vehicles to break the stalemate.
The tank was envisioned as an armoured machine that could cross ground under fire from machine guns and reply with its own mounted machine guns and cannons. These first British heavy tanks of World War I moved on caterpillar tracks that had lower ground pressure than wheeled vehicles, enabling them to pass the muddy, pocked terrain and slit trenches of the Battle of the Somme; the tank proved successful and, as technology improved. It became a weapon that could cross large distances at much higher speeds than supporting infantry and artillery; the need to provide the units that would fight alongside the tank led to the development of a wide range of specialised AFVs during the Second World War. The Armoured personnel carrier, designed to transport infantry troops to the frontline, emerged towards the end of World War I. During the first actions with tanks, it had become clear that close contact with infantry was essential in order to secure ground won by the tanks. Troops on foot were vulnerable to enemy fire, but they could not be transported
The Lotus 25 was a racing car designed by Colin Chapman for the 1962 Formula One season. It was a revolutionary design, the first stressed monocoque chassis to appear in Formula One. In the hands of Jim Clark it took 14 World Championship Grand Prix wins and propelled him to his 1963 World Championship title, its last World Championship win was at the 1965 French Grand Prix. An early brainchild of Chapman's fertile mind, the original sketches for the car were made on napkins while Chapman discussed his idea while dining out with Frank Costin; the unveiling of the 25 at Zandvoort in 1962 was a shock for the competition, for teams like Brabham and UDT/Laystall who had purchased 24s from Lotus, with the understanding that they would be "mechanically identical" to the works cars - Chapman reserved the right to alter the bodywork of the cars. The monocoque made the car structurally stronger than typical F1 cars of the period; the 25 was three times stiffer than the interim 24. The car was low and narrow, with a frontal area of 8.0 ft², 0.74m² as compared to the normal 9.5 ft², 0.88 m² It was envisaged to have a column gear lever, to keep the cockpit width to a minimum, although this was only experimental and discarded.
To assist the low profile and low frontal area, the driver reclined behind the wheel, leading to the nickname'The Bathtub', while front coil/damper units were moved inboard. The 25 was powered by the Mk. II 1496cc through to the Mk.5 1499cc versions of the Coventry Climax FWMV V8 in crossplane and flatplane formats. Reg Parnell Racing in 1964 fitted BRM P56s of similar specification to their second-hand 25s; such was the 25's effect on motor racing today's modern F1 cars follow its basic principles. Some privateers, buying Lotus chassis were disgruntled by the fact Chapman refused to provide them 25s; these teams, including Rob Walker Racing, were given Lotus 24s, while the works team had exclusive use of the 25 for Jim Clark and Trevor Taylor. When it first appeared at the Dutch Grand Prix, the futuristic 25 was inspected by John Cooper, who asked Chapman where he had put the frame tubes in the car. Seven cars were built in total, numbered R1 to R7. Four cars - R1, R2, R3 and R5 - were written off in accidents between 1962 and 1966.
The most successful was R4, which Clark drove to all seven of his World Championship wins in 1963. This car was crashed by Richard Attwood rebuilt as a Lotus 33 using a spare monocoque of that type and unofficially known as R13; the car gave Clark his first World Championship Grand Prix victory, at Spa in 1962. He took another win in Britain and again in the USA, which put him in contention for the title, but while leading the final race in South Africa a much publicised engine seizure cost him the title to Graham Hill. Clark gained his revenge the following year, taking his first World Championship in the 25, by winning 7 races, France, Britain, South Africa, Mexico. Lotus won its first constructors' championship. Following the United States GP, a 25 was taken to the Indianapolis Motor Speedway for evaluation, where they trialled Lucas electronic ignition for Ford; the results were encouraging enough for Colin Chapman to mount his successful challenge on the Indianapolis 500. The 25 was again used during the 1964 season.
At the final race in Mexico, just as in 1962, the Climax engine developed an oil leak and with a lap to run Clark coasted to a halt in sight of world championship victory, this time conceding to John Surtees. Despite the introduction of the Lotus 33 in 1964, the 25 was still used until well into the 1965 season, Clark taking the car's final win at the 1965 French Grand Prix. In 1964, Reg Parnell Racing began using the BRM P56 V8 engine, with limited success. Chris Irwin placed Reg Parnell Racing's 25/33 hybrid 7th in its final World Championship race at the 1967 Dutch Grand Prix, scene of the model's debut five years earlier. 1 Points were awarded on a 9-6-4-3-2-1 basis to the first six finishers at each round, but only the best placed car for each make was eligible to score points. In 1962 and 1966 only the best five results from the season were retained, only the best six results for 1963, 1964 and 1965. In 1967 the best five results from the first six rounds and the best four results from the last five rounds were retained.
2 Jack Brabham raced. 3 Plans for Arundell to race the spare car were abandoned. 4 Clark swapped cars with Spence's Lotus 33 during the race following mechanical problems. 5 Revson tried out Hailwood's car in practice while the latter was away qualifying for the TT. 6 Total points scored by all Lotus-Climax cars, including 45 points scored by drivers of Lotus 33 variants. 7 Total points scored by all Lotus-Climax cars, including 8 points scored by drivers of Lotus 33 variants. In June 2008 Lotus launched a special edition of the Elise supercharged model, the Type 25 Jim Clark, in the Lotus racing colours of green with a yellow stripe; this had traction control. A total of 25 of these cars were produced for the RHD market. Media related to Lotus 25 at Wikimedia Commons
The RG-33 is a mine-resistant light armored vehicle designed by BAE Systems Land Systems South Africa a South African subsidiary of BAE Systems. BAE Systems in the US extensively modified it with additional protection, new power train and suspension systems, it was built in a number of locations including Pennsylvania. It was one of several vehicles being fielded by the US Armed Forces in Iraq under the MRAP program, it is based on the RG-31, which itself is based on the Mamba APC, although it is twice the weight of a RG-31. There are two variants, the standard RG-33 has four wheels and weighs 22 tons while the extended RG-33L variant has six wheels, can carry twice as many people in the back, weighs 26 to 37 tons depending on the version, it was selected to be the sole producer of the US Army's $2.88 billion Medium Mine Protected Vehicle program. The initial contract is worth $20 million. BAE representative Doug Coffey says that live-fire testing at Aberdeen, proved the RG-33 to be the overall most survivable MRAP vehicle.
The RG33 is manufactured in several configurations including the category I 4×4, category II 6×6, the heavy armored ground ambulance and the special operations command vehicle. It features a monocoque armored v-hull, for maximized interior space and footrests suspended from the ceiling, run-flat tires, an optional armored glass turret, for maximized visibility and protection; the monocoque hull does not extend under the engine like some other armored vehicles. The engine compartment is a separate moncoque structure; the vehicle is notable for its extensive use of TRAPP armored glass in the crew compartment. Like the Buffalo, it can be equipped with a robotic arm; the U. S. has fielded 259 RG-33 4x4 variants in a Special Operations Command configuration as shown above with remote weapon stations, two extra seats, a rear door assist. The U. S. has fielded 16 RG-33L 6x6 variants in a Heavy Armored Ground Ambulance configuration. The Pentagon has future plans to add the Crows II remote weapon station, Boomerang anti-sniper system, the Frag Kit 6 anti-EFP armor.
On 26 January 2007, four RG-33s were delivered to the United States Marine Corps for testing. On 14 February, an order for 15 MRAP Cat 1 RG-33s and 75 MRAP Cat 2 RG-33Ls was placed under an Indefinite Delivery, Indefinite Quantity contract. On 28 June, BAE received a $235.8M order for 16 RG-33 Cat 1 patrol vehicles, 239 RG-33L Cat 2 vehicles, 170 RG-33 Cat 1 variants for the United States Special Operations Command, out of their total allotment of 333 vehicles, 16 RG-33L Cat 2 Ambulance variants, which are the first vehicles in the competition listed for the ambulance role. The vehicle can be mission configured for a number of roles including Infantry Carrier, Ambulance and Control, Convoy Escort and Explosive Ordnance Disposal. On 18/Oct, an additional order for 600 MRAPS was received, involving 399 RGL-33L Cat 2, 112 RGL-33L Cat 2 Ambulance variants and 89 RG-33 SOCOM for 322 Million dollars. On Dec/18/07 a further order for 600 RG-33L Cat 2 was awarded to BAE Systems, for 645 Million dollars.
To date, this gives a total of 1,735 RG-33 vehicles being ordered by the US Military. On 2 December 2012, BAE received a $37.6 million contract to convert 250 RG-33L 6×6 vehicles up to the Medium Mine Protected Vehicle status. Differences include a rear ramp for deploying unmanned ground vehicles, a new heating and air conditioning system, larger modular interior, high mobility chassis, extensive equipment options, larger bullet-resistant windows, 360-degree situational awareness suite. RG-33 RG-33L Burundi In service with the Burundian military. Croatia Croatian Army Djibouti Djiboutian Army - 10 RG-33 Egypt Egyptian Army - 260 RG-33L + 90 RG-33L HAGA Nigeria Took delivery of 24 RG-33s after being refurbished. United States United States Army United States Marine Corps United States Special Operations Command Buffel Casspir List of AFVs Mamba APC Matador Medium Mine Protected Vehicle - The U. S. Army Equivalent to the MRAP Program MRAP - U. S. Military Mine Resistant Ambush Protected Vehicle Program Nexter Aravis RCV-9 RG-12 RG-19 RG-31 RG-32 RG-34 RG-35 baesystemspresskit.com, Deagel.com: RG-33
A vehicle frame known as its chassis, is the main supporting structure of a motor vehicle, to which all other components are attached, comparable to the skeleton of an organism. Until the 1930s every car had a structural frame, separate from its body; this construction design is known as body-on-frame. Over time, nearly all passenger cars have migrated to unibody construction, meaning their chassis and bodywork have been integrated into one another. Nearly all trucks and most pickups continue to use a separate frame as their chassis; the main functions of a frame in motor vehicles are: To support the vehicle's mechanical components and body To deal with static and dynamic loads, without undue deflection or distortion. These include: Weight of the body and cargo loads. Vertical and torsional twisting transmitted by going over uneven surfaces. Transverse lateral forces caused by road conditions, side wind, steering the vehicle. Torque from the engine and transmission. Longitudinal tensile forces from acceleration, as well as compression from braking.
Sudden impacts from collisions. Types of frame according to the construction: Ladder type frame X-Type frame Off set frame Off set with cross member frame Perimeter Frame Typically the material used to construct vehicle chassis and frames is carbon steel. In the case of a separate chassis, the frame is made up of structural elements called the rails or beams; these are ordinarily made of steel channel sections, made by folding, rolling or pressing steel plate. There are three main designs for these. If the material is folded twice, an open-ended cross-section, either C-shaped or hat-shaped results. "Boxed" frames contain chassis rails that are closed, either by somehow welding them up, or by using premanufactured metal tubing. C-shape By far the most common, the C-channel rail has been used on nearly every type of vehicle at one time or another, it is made by taking a flat piece of steel and rolling both sides over to form a c-shaped beam running the length of the vehicle. Hat Hat frames resemble a "U" and may be either right-side-up or inverted with the open area facing down.
Not used due to weakness and a propensity to rust, however they can be found on 1936–1954 Chevrolet cars and some Studebakers. Abandoned for a while, the hat frame gained popularity again when companies started welding it to the bottom of unibody cars, in effect creating a boxed frame. Boxed Originally, boxed frames were made by welding two matching C-rails together to form a rectangular tube. Modern techniques, use a process similar to making C-rails in that a piece of steel is bent into four sides and welded where both ends meet. In the 1960s, the boxed frames of conventional American cars were spot-welded here and there down the seam. While appearing at first glance as a simple form made of metal, frames encounter great amounts of stress and are built accordingly; the first issue addressed is the height of the vertical side of a frame. The taller the frame, the better it is able to resist vertical flex when force is applied to the top of the frame; this is the reason semi-trucks have taller frame rails than other vehicles instead of just being thicker.
As looks, ride quality, handling became more important to consumers, new shapes were incorporated into frames. The most visible of these are kick-ups. Instead of running straight over both axles, arched frames sit lower—roughly level with their axles—and curve up over the axles and back down on the other side for bumper placement. Kick-ups do the same thing, but don't curve down on the other side, are more common on front ends. Another feature seen are tapered rails that narrow vertically and/or horizontally in front of a vehicle's cabin; this is done on trucks to save weight and increase room for the engine since the front of the vehicle does not bear as much of a load as the back. Design developments include frames. For example, some pickup trucks have a boxed frame in front of the cab, narrower rails underneath the cab, regular C-rails under the bed. On perimeter frames, the areas where the rails connect from front to center and center to rear are weak compared to regular frames, so that section is boxed in, creating what is known as torque boxes.
So named for its resemblance to a ladder, the ladder frame is one of the simplest and oldest of all designs. It consists of two symmetrical beams, rails, or channels running the length of the vehicle, several transverse cross-members connecting them. Seen on all vehicles, the ladder frame was phased out on cars in favor of perimeter frames and unitized body construction, it is now seen on trucks. This design offers good beam resistance because of its continuous rails from front to rear, but poor resistance to torsion or warping if simple, perpendicular cross-members are used; the vehicle's overall height will be greater due to the floor pan sitting above the frame instead of inside it. The term unibody or unit body is short for unitized body, or alternatively unitary construction design, it is A type of body/frame construction in which the body of the vehicle, its floor plan and chassis form a single structure. Such a design is lighter and more rigid than a vehicle having a separate body and frame.
Traditional body-on-frame architecture has shifted to the lighter unitized body structure, now used on most cars. The last UK mass-produced car with a separate chassis was the Triumph Herald
The Zeppelin D. I, or Zeppelin-Lindau D. I or Zeppelin D. I sometimes referred to postwar as the Dornier D. I or Dornier-Zeppelin D. I, for the designer, was a single-seat all-metal stressed skin monocoque cantilever-wing biplane fighter, developed by Claude Dornier while working for Luftschiffbau Zeppelin at their Lindau facility, it was too late to see service with the German Air Force during World War One. The Dornier D. I was one of several designs by Claude Dornier to have an all-metal stressed skin monocoque structure, it was the first fighter to feature such construction and although production was cancelled prior to the completion of any production versions, it was the first aircraft with these features to go into production. To reduce the hazards of inflight fires, it had an external fuel tank, according to some sources may have been jettisonable, thick-section cantilevered wings for improved aerodynamics; the Dornier Do H Falke was developed from it, but had an enlarged upper wing and dispensed with the lower wing.
Seven prototypes were built as part of the development program. It was never used operationally, due to the end of World War I. Luftstreitkräfte pilots again in October. German ace Wilhelm Reinhard was killed on 3 July 1918 after a structural failure, while it was supposed to have been grounded for structural improvements. There were poor climb performance at higher altitudes. After being fitted with a more powerful BMW IIIa inline-six liquid-cooled engine that boosted the climb rate to 5,000 m from 25 minutes to 13 minutes, an order was placed for 50 aircraft either in October or November; the airframes for this order were 50 percent complete when production was halted in early 1919. One of the prototypes went to the US Navy and another to the US Army Air Service, both purchased in 1921 and delivered in 1922, for evaluation of the novel construction methods used. German EmpireLuftstreitkräfte - evaluation only United StatesUnited States Navy - one example for evaluation, serialed A6058 United States Air Service - one example for evaluation, serialed AS.68546, McCook Field Project Number P.241 None of the examples built survive.
Data from Grey, 1970, p.580General characteristics Crew: one pilot Length: 6.37 m Wingspan: 7.8 m Height: 2.6 m Wing area: 18.7 m2 Empty weight: 725 kg Gross weight: 885 kg Powerplant: 1 × BMW IIIa water cooled inline 6 cylinder, 138 kW Performance Maximum speed: 200 km/h Service ceiling: 8100 m Armament 2 × fixed, forward-firing Spandau machine guns Related development Dornier-Zeppelin C. II - two-seater with conventional wings but similar fuselage and developed in parallel. Dornier Do H FalkeAircraft of comparable role and era Fokker D. VII Junkers D. I LFG Roland D. XV Pfalz D. XII Short Silver Streak Related lists List of fighter aircraft Idflieg aircraft designation system List of military aircraft of the Central Powers in World War I Grosz, Peter. Dornier D. I Windsock Mini datafile # 12. Hertfordshire, UK: Albatros Publications. ISBN 9780948414923. Gray, Peter. German Aircraft of the First World War. London: Putnam. P. 580. Hundertmark, Michael. Phoenix aus der Asche - Die Deutsche Luftfahrt Sammlung Berlin.
Berlin: Silberstreif Verlag. ISBN 978-3924091026. Kössler, Karl. Dornier - Die Chronik des ältesten deutschen Flugzeugwerks. Friedrichshafen, Germany: Walter Biering GmbH. p. 78. ISBN 3-925505-01-6. Ogden, Bob. Dornier - Flypast Reference Library. Lincs, England: Key Publishing. ISBN 0 946219 05 2. LCCN 0263-5887. Sheppard, Milton. "Dornier D. I Static Test". Cross & Cockade. Society of WW1 Aero Historians. 9: 391–395. Terry, Gerard. "The Development of Dornier Landplanes 1914-1918". Cross & Cockade Great Britain Journal. Society of WW1 Aero Historians. 12: 97–117. Unknown author. "Some "Dornier" Milestones". Flight. Flight Magazine. Pp. 1269–1273 and pp.1289–1292
NR500 was an innovative racing motorcycle developed by Honda HRC in 1979 to compete in Grand Prix motorcycle racing. The NR stood for New Racing; the motivation behind the NR500 was company founder Soichiro Honda's desire to compete using four-stroke engine technology since the majority of motorcycles manufactured by Honda used four-stroke engines. When the FIM announced new regulations for the 1968 Grand Prix motorcycle racing season that limited the 500 cc engines to four cylinders, this gave an advantage to teams using two-stroke machinery. Honda decided to withdraw from motorcycle racing to concentrate on its automobile division. In November 1977 Honda announced it would be returning to motorcycle Grand Prix racing using four-stroke technology. Though two-stroke engines dominated motorcycle Grand Prix racing in the late 1970s, Honda felt bound by their convictions to race what they sold and thus decided to compete using a high-technology, four-stroke race bike. Since a conventional four-stroke, four-cylinder engine could not produce the same power of its two-stroke rivals, Honda had to increase the valve area in order to be competitive.
The rules at the time allowed up to four combustion chambers so Honda designed a 32-valve V8 with four pairs of linked combustion chambers. This evolved into an innovative engine with four oval-shaped cylinders; the oval cylinders allowed room for 32 valves and eight spark plugs, the same as that of an eight-cylinder engine while staying within the four-cylinder rules limit. Another innovation used on the NR500 was its monocoque body which wrapped around the engine like a cocoon and helped reduce weight. In an effort to reduce drag, lower the center of gravity and to lower gyroscopic forces, the bike used 16-inch Comstar wheels instead of the mainstream 18-inch versions that were commonplace at the time. Honda overcame significant manufacturing problems to develop its oval cylinder technology and by late 1979 the bike made its much-anticipated debut at the British Grand Prix ridden by Mick Grant and Takazumi Katayama. Both bikes retired, Grant crashing out on the first turn after the bike spilled oil onto his rear tire, sliding along with the bike showering sparks, requiring rapid application of powder fire retardant from the race-marshall.
Katayama retired on the seventh lap due to ignition problems. Honda never made the bike competitive; the monocoque frame had to be abandoned because it made it too difficult for mechanics to work on the engine during races. The 16-inch wheels had to be abandoned for 18-inch wheels. American Freddie Spencer was able to reach 5th place at the 1981 British Grand Prix before the bike broke down; the NR500 never won a Grand Prix, a thirteenth place by Katayama at the 1981 Austrian Grand Prix being its best showing. Honda decided to abandon the project and designed the NS500 two-stroke bike to compete in the 1982 season. Spencer would ride the NS500 to Honda's first 500 cc world championship in 1983. What doomed the NR500 project was that Honda had tried to develop too many technologies at one time; the NR500 did experience a few successes. Freddie Spencer rode the NR500 to a heat race victory at Laguna Seca in 1981 and Kengo Kiyama won the Suzuka 200 kilometer race that same year
In mechanical engineering, stressed skin is a type of rigid construction, intermediate between monocoque and a rigid frame with a non-loaded covering. A stressed skin structure has its compression-taking elements localized and its tension-taking elements distributed; the main frame has rectangular structure and is triangulated by the covering. A framework box can be distorted from being square, so it isn't rigid by itself, however adding diagonals that take either tension or compression fixes this, because the box cannot deviate from right angles without altering the diagonals. Sometimes flexible members like wires are used to provide tension, or rigid compression frames are used, as with a Warren or Pratt truss, however both these are full frame structures; when the skin or outer covering is in tension so that it provides a significant portion of the rigidity, the structure is said to have a stressed skin design. This may be referred to as semi-monocoque, overlaps with monocoque, which has less framing, sometimes only including longitudinal or lateral members and overlaps with rigid frame structures where a minor portion of the overall stiffness may be derived from the skin.
This method of construction is lighter than a full frame structure and not as complex to design as a full monocoque. Examples include nearly all modern all-metal airplanes, as well as some railway vehicles and motorhomes; the London Transport AEC Routemaster incorporated internal panels riveted to the frames which took most of the structure's shear load. Automobile unibodies are a form a stressed skin as well, as are some framed buildings which lack diagonal bracing. Dornier-Zeppelin D. I: first all-metal stressed skin fighter and first with stressed skin wings Short Silver Streak: first all-metal British stressed skin aircraft Zeppelin-Lindau Rs. IV: first aircraft with an all-metal stressed skin fuselage to fly Zeppelin-Staaken E-4/20: first all-metal stressed skin four-engine airliner Northrop Alpha: first American all-metal stressed skin aircraft GM New Look bus: stressed skin bus, over 44,000 built since 1959, many still in service. Stressed Skin Wood to Metal: The Structural Origins of the Modern Airplane