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[boeing747430]

The aim for the manufacturer is to design the non-normal-checklist as simple as possible while guaranteeing the subsequent safe operation of the aircraft. The NNCs will never be able to cover all possible failures of a discrete system. Sometimes, some steps obviously make no sense (switching on demand pumps, when no hydraulic fluid is left). Still, if you follow all steps, you will have a safe aircraft to fly - not one with optimum switching to get as much performance out of a damaged system.

The 747 and its NNC-design greatly benefits from the aircraft's massive system redundancy. All the NNCs have to fit into the QRH, so they are simplified and shortened as much as possible. For example, there is no NNC for landing the 747 without any flaps anymore. There used to be one.

Having flown 320s for 14 years, I appreciate the simplicity of the 747s NNC design. Some 320 abnormal checklists were very complex and no one was able to remember all ECAM messages. On the 747, one can remember all EICAS messages. At least you will have seen most during your transition training. Not so for A320s.