Just one priceless gem from that site:
The landing gear is built in the same way as in ordinary aircraft. The extreme conditions where they are used make the task difficult. After the plane has taken off the front landing gear, for instance, is tucked up into the hydrogen tank, temperature below -250 C . The front landing gear will then become cold and the rubber in it becomes as hard as glass and can go to pieces with the slightest bump. When descending the same rubber becomes easily heated and can burn even though it is sheltered by ceramic tiles. At least the materials for the front landing gear have to be chosen from other than the present day materials.