Jesus, why does this thing about monocoque keep coming up? I know you're asking mostly about the post-CCA era, but monocoque simply doesn't figure as a possibility.
According to the current tech of the Universal Century,
no Mobile Suits ever had Monocoque frames. It has been quietly swept under the carpet, and it no longer matters. Semi-monocoque does not exist either. GMs, the Gundam, etcetera, all used a skeleton covered by armour. The point of the movable frame in the Gryps era is less armour weight, more thrusters which are built into the skeleton rather than bolted-on it, and the occasional model with binders to help manouverability.
To end this, I'll refer you to
this thread.
And I'll quote two bits from that thread:
Kosh wrote:Early on in the 80s, when Gundam started getting more tech-savvy and the fan culture was growing, it was officially declared that the basic design principles of the Federation and Zeon were different. As you say, the Federation sported internal skeletons upon which armour and thrusters were added. Zeon, according to this, used monocoque designs, much like what you'd find in a car.
Upon closer scrutiny, this idea is completely bunk. A Mobile Suit with a monocoque design would crumble upon its own weight. Imagine a human body with no skeleton and you have a pretty good idea of what would happen.
Basically considering present-day MG and PG models, this idea has been mostly retconned out (...) The Zakus clearly have internal skeletons. The big difference between the Fed and Zeon now is that the Feds always placed emphasis on lighter models, whereas Zeon focused on armour, uh... mour.
The movable frame is simply the idea of making the skeleton the most important part of the design, with armour being used, IN THEORY, to protect only the vitals of the MS. Of course, animation wise this doesn't always happen (the Mk-II shows some internals, but look at other later Zeta MS and they don't look like that was kept in mind in their visual design).
And, of course, from Mark himself:
toysdream wrote:The old monocoque theory seems to have been quietly taken out back to the glue factory.
This means that the "movable frame" concept isn't such a radical departure from the earlier methods, but it does have a couple of distinguishing features. The most important is that, in a movable frame design, the frame incorporates virtually all the mobile suit's vital mechanisms--power systems, motors, hydraulics, avionics, thrusters, and pretty much everything else except weapons, armor, and propellant tanks. In earlier designs, the frame was mainly for structural support, with everything else bolted onto it and the armor wrapping everything up.
-- Mark
(The posts Kosh brought up were pretty helpful at least.)
