The A340 is the first long-haul Airbus aircraft with four engines. Its optimized hull diameter allows for quick entry and disembarkation using two passenger aisles. After the introduction of this model the aircraft quickly became criticised by pilots. The unusually weak engines did not blend well with the "supercritical" structure of the A340. Thus, only a slight climb was possible, the cruise speed was lower than that of the already established Boeing jumbos. The approach to the optimal glide slope was indeed cost-effectively flat, but you needed getting used to it in comparison to other aircraft.
Since its first flight in 1991 the A340 has seen a number of successful developments and design variations. After several hull extensions and with ever more powerful engines it became the longest passenger plane ever, the A340-600. With standard seating, it can carry up to 380 passengers.

Technical Data (A340-600)

Length	75,30 m		Max. Take-off Mass	368.000 kg
Height	17,80 m		Max. Take-off Thrust	4x 249 kN
Wing Span	63,45 m		Max. Operational Range	13.900 km
Hull Diameter	5,64 m		Max. Landing Mass	259.000 kg

For more information see the site of the manufacturer Airbus 

Fly the Airbus A340 Full Flight Simulator

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