Expert: Ray Wilkinson - 5/5/2007

Question
Hi MR RAY,
well thank you so much for your answer.anyhow sir i want to ask you about A380 landing gear
can you please explain to me how the pressure exerted by A380 wheels is lower than that of a Boeing 747 or Boeing 777? and how could the load distributed in it's wheels? please sir can you explain to me?
thank you sir


Answer
Hi again Farid

Pressure is Force/Area, and the A380 has 26 wheels compared to the 18 of the 747 and the 14 of the 777. Although the weight is higher than either of the Boeings, the pressure can be lower as it's shared over more wheels. The other thing that makes a difference to the area is the size of the tyres, of course - if the A380 has larger diameter tyres, or they are wider, that will reduce the ground pressure.

The damage (wear) done to the runway increases hugely as contact pressure increases, so operators may be charged more for landing an aircraft with higher contact pressure, even if it's lighter than another aircraft.

I hope this answers your question.

Regards

Ray