LMP737: The 7E7 is not the only aircraft using the VSCF electrical system. Airbus is using it on the A380 as well. Having some experience on the MD-90 hopefully both manufacturers will look at the 90 and learn from it. Main trick will be to make the system not as sensitive and more fault tolerant.
I may be wrong there, but as far as I know, the MD
-90 used an electronic rectifier/inverter combination to convert the original variable frequency power into constant frequency for the onboard systems. This electronic power converter is reported to have had major reliability problems.
At least the A380 and as far as I know the 7E7 as well don´t have a constant frequency bus - all onboard systems are supplied with variable frequency power and have to cope with that, which isn´t a big deal nowadays.
Both approaches are trying to do away with the constant speed drive generators to save weight and maintenance; But the prospects are somewhat more positive this time around.
Tasha: To the question of FBW: How really important is that in an airliner? Think about it. These aircraft are NOT designed to do aerobatics and other violent maneuvers.
That´s not the point. First, it saves on complexity, weight and maintenance.
Only after that there is a potential for the introduction of additional capabilities: A more "intelligent" plane.
One side effect is the possible elimination of high speed ailerons, for instance: The computers can compensate airspeed automatically.
Airbus made the next step beyond that: They introduced an abstraction layer between pilot command and control surface movement. This abstraction layer eliminates some of the workload and enables the creation of a straightforward cross-model behaviour that simply wouldn´t be possible without FBW. Autotrim, for instance, is seamlessly integrated into the behaviour of the plane - no need to even think about it.
Hard protection (also impossible without FBW) primarily allows the pilot to fly extreme maneuvers that would be much too risky otherwise, in case of an impending collision or other problems where it really counts. The plane will give exactly the maximum possible, not more, but more importantly not less
than that. No need to "leave room" in the envelope manually, especially in an already stressful situation.
In these respects, Boeing simply didn´t use the potential with the 777; But it seems they´re beginning to move a little more in the same direction with the 7E7 now...