Airbus measured pavement loads using a 540-tonne (595 short tons) ballasted test rig, designed to replicate the landing gear of the A380. The rig was towed over a section of pavement at Airbus' facilities that had been instrumented with embedded load sensors. It was determined that the pavement of most runways will not need to be reinforced despite the higher weight, as it is distributed on more wheels than in other passenger aircraft with a total of 22 wheels (that is, its ground pressure is lower). The A380 undercarriage consists of four main landing gear legs and one noseleg (a layout similar to that of the 747), with the two inboard landing gear legs each supporting six wheels.