His 1893 Flying Machine had 50 lifting surfaces and used his patented "double-surface airfoils" in such a way as to produce an aspect ratio of 1:152, providing great lift at the sacrifice of stability. As a test vehicle, it was not designed to be manned, but was used to test lifting capability. Its maximum load was found to be 400 lb (180 kg).[3] His 1904 Multiplane was a development of the 1893 test vehicle in a configuration that could be flown by a person.