I try to use it, but I don't think I understand it. In the newer FMC equip models, the FD is driven by what you program in the FMC/MCP so it guides you to achieve that both laterally and vertically. But this FD is independent and it does work for lateral guidance, but for vertical guidance I have to change the pitch? I guess you're just supposed to set it to standard degree's of angle? In the newer models, if I have to maintain 250 knots, the FD shows me where to be.