Back in the early 70s, airlines around the world began to show interest in medium-capacity liners (about 200 seats) with good take-off and landing data and capable of operating on long routes. At that time, the European Airbus Industry consortium began work on projects of A-series machines, the best airbus aircraft. Many technical innovations of previous years were embodied in these projects. First of all, the consortium set a goal to significantly reduce fuel consumption and the price of aircraft. A third of the fuel economy was supposed to be the result of increased engine efficiency, another third ≈ aerodynamic improvement, the rest due to a decrease in the mass of the aircraft. The aircraft must be operated by a crew of two people: the commander and the co-pilot. Already then it became clear that it was necessary to create a whole “family” of aircraft, differing in size, but, most importantly, almost identical in basic structural elements, production technology, and operation.
Ten years later, on April 3, 1982, the first flight of the base aircraft A-310-200 took place. Then came the smaller A-319, A-320, A-321. The number of orders for airbuses exceeded the expectations of firms. “Appetite came with eating”: Airbus Industry proposed the creation of the A-330 and A-340, even larger sizes, differing only in the number of engines (four engines in the A-340). The main concept of the A-340 is ultra-long-distance airlines, where its economic efficiency should be manifested. The aircraft is available in two versions A-340-200 and A-340-300. The configuration of the passenger compartment provides for the placement of 262 passengers for the option “200”, including 18 first-class, 74 business, and 170 economic. For the “300” version, respectively – 295 passengers and in classes 18, 81, and 196. Modifications of gliders consisted mainly in strengthening the wing and landing gear and installing additional fuel tanks. Their installation and the fuel transfer system were carried out so that rear alignment was provided (for example, one of the tanks was in the horizontal tail). The result is an increase in flight efficiency, by reducing negative lift on the horizontal tail and, therefore, drag.
The A-340 is a monoplane with a freely bearing sagittal mid-wing wing with a span of 60.3 m. The aerodynamic profile of the wing is unique, as it can be used on both the A-330 twin-engine aircraft and the A-340 four-engine aircraft. The large elongation and the presence of end aerodynamic surfaces (with a side inclination of 42.5 °) provide high quality – 10 and a decrease in inductive resistance. The wing has a large relative thickness, which increases its structural efficiency and internal volumes for fuel. Improved load-bearing properties can reduce the area to 363 m2, the total mass of the structure, and fuel consumption. The wing is made of high strength aluminum alloys and composite materials. Monolithic cladding panels and other parts obtained by machining blanks are widely used. This simplifies assembly, and also reduces production costs and achieves better performance. The use of large integration components provides mass savings compared to prefabricated components and reduces the number of potential breakdown zones sealing (which reduces the need for sealants).
The exclusion of lap joints and the small number of bolt holes reduce the number of places where cracks can arise. On each console there are flaps and, interestingly, seven sections of slats, occupying almost the entire length of the leading edge. Both the flaps and the slats are automatically controlled by flight parameters using EDSU and executive hydraulic boosters. The wing has internal ailerons and interceptors. This increases the efficiency of lateral control and improves cruising aerodynamics of the wing, simplifies its design. Management is duplicated for reliability by three hydraulic systems.
The aircraft fuselage is a sealed semi-monocoque frame structure, round in cross-section. The length for the 200 is 59.39 m, for the 300 it is 63.65 m. The height of the aircraft is 16.8 m. The plumage of the cantilever structure is of a conventional type, with a sweep over all surfaces. Its design is made with the widespread use of composite materials, which gives a significant reduction in weight. The aircraft has a three-post retractable landing gear with an articulated suspension of wheeled trolleys. Nose rack with dual steered wheels. Each main tack with two two-wheeled carts, with a tandem wheel arrangement, retractable in the fuselage. The braking system is automatic. The base of the chassis is 23.2 m for the 200 and 25.4 for the 300.
The power plant consists of four CFM 56-5C2 engines with a thrust of 4×146.3 kM = 585.2 kM. Increased engine efficiency is achieved as a result of continuous improvement of the main engine components. So, SNEKMA increased fan efficiency by changing the configuration of the blades, reduced the gaps between the ends of the rotor blades and the motor housing. The use of an electronic digital engine control system ensures the accuracy of maintaining engine parameters at optimal economic values and enables the pilot to control the engine thrust directly by the ore. Also, this system is significantly reduced in mass and has significantly reduced the cost of maintenance.
The A-340 has a laser gyroscopic system and a satellite-based orientation system. All navigation systems allow the crew to fly automatically. A special device for determining the center of gravity gives the appropriate signal to set the depth rudder trimmer. The main difference from the A-320 and A-321 is the large dimensions of the cab and devices for 4 motors, a slightly modified ceiling panel. Six multifunction displays are installed on the front of the instrument panel: the external screens work like “flight displays” (primary information), and the middle ones like navigation displays. Both middle screens are also used to transmit information about the parameters of systems and engines in an emergency. The backup circuit on the display, when all devices are turned off, provides the pilot with the control and landing of the aircraft. Its parameters: flight speed, altitude, horizon, gyromagnetic course, VOR (a device similar to our ARC). The crew seats of the new generation – with an electric control system along three axes and a tiltable backrest. The position of the pedals is adjustable. The height of the armrests is adjustable. Left and right mounted side handlebar and aileron control knobs. Closer to the board are the front wheel control knobs.
The triumphant success of the A-340 at the Salon was facilitated by its round-the-world flight, during which he set several world records with take-off and landing at Le Bourget. The flight route 38,360 km was covered in 48 hours 20 minutes, including the time for a single stop for refueling in Auckland (New Zealand). To guarantee, an additional fuel tank of 28 tons was installed (the total amount of fuel before takeoff was 140 tons).
- Modification: A340-200
- Wingspan, m: 60.30
- Aircraft Length, m: 59.39
- The height of the aircraft, m: 16.70
- Wing Area, m2: 361.60
- Weight kg: empty curb aircraft 129000; maximum take-off 275,000
- Engine type: 4 turbofan General Electric CFM56-5C4
- Thrust, kg/f: 4 x 15422
- Maximum speed, km / h: 988
- Cruising speed, km / h: 938
- Practical range, km: 14816
- Crew: 2
- The payload is 261 passengers in a three-class configuration or 239 passengers in a two-class configuration or 30800 kg of cargo.