Can somebody comment on the actual design of the hydraulic valve part where the fault occurred? I mean, if a pinhead-size O-ring fragment can block this small orifice and thereby prevent both normal LG extension and the emergency extension method? I can understand that putting a filter in each and every hydraulic line is not practical. But if this hydraulic valve part had two small orifices instead of one, maybe the landing gear would still have functioned even if one was blocked?
