Undercarriage Leg and Wheel Assembly for Airbus A340 Aircraft

This Undercarriage Leg and Wheel Assembly for Airbus A340 Aircraft was built in 1995 by Messier-Dowty Limited in Gloucester.

This four-wheeled assembly is 5.2 meters tall when fully extended, and weights approximately 5400 kg. The key components include articulating bogie unit, which is a horizontal mechanism connecting the four wheels, which is connected to the ultra-high tensile steel main fitting and piston via a piston, front facing torque links and a rear facing articulating mechanism which can lower the rear two wheels lower than front two wheels.

One of the worlds largest landing gears ever designed for commercial service, this massive assembly is over five meters tall when fully extended, and its development helped pave the way for 21st century commercial air travel.

Developed in 1995 by Messier-Dowty Limited, a joint French-British venture aimed at innovating on established aircraft landing and braking systems.

In 1991, Airbus has begun the development of its A340-300 series of commercial airliners, notable for its then exceptional size, weight capacity and potentially 440 passengers and crew. No landing gear system previously developed was capable of meeting the ambitious requirements of this new supersized plane, leading to the development of this game-changing system.

The key innovation of this design is its four-wheel articulating rigid bogie which allows the rear two wheels to be extended further towards the ground to make contact with the surface first, with the front two wheels of the gear connecting after. This feature, alongside its novel method of shortening as it retracts into the lower fuselage after takeoff, meant this landing gear system contributed minimally to the plane’s weight, making landings softer and more controlled.

It was estimated by Messier-Dowty Ltd that this model of landing gear would, over the course of its life, travel between 250,000 and 500,000 miles on ground with an average tire life of around 300 landings.

This innovative design received a Queen’s Award for Technological Achievement in 1995 for the successful and technologically novel approach this ultra large landing gear’s design. At the height of its use, this specific design of landing gear was fitted on over 14,000 airplanes which made 20,000 takeoffs and landings each day. Its design has inspired most landing gear development since and opened the door for larger and larger commercial aircraft in the 21st century.

Messier-Dowty Limited, originally owned by the TI Group, was quicky purchased by SNECMA group in 1998, which eventually merged with French SAGEM company to form Safran Landing systems in 2011. Messier-Dowty’s original Gloucester site remains active as one of the worlds largest design and testing sites for landing gears as well as a prominent manufacturing facility.