Originally Posted by
riff_raff
The 53K MRGB ... It is a (12 way) torque split configuration designed for very high power (>16,000hp) and low specific weight (over 500lbs less than planetary config). Torque split designs are notoriously difficult to get right because the multiple load paths present a very complex analysis case. The 53K MRGB relies on torsionally compliant quill shafts and precision assembly to provide the required balance of torque distribution among 12 pinions driving the bull gear. Anyone that has experience working with this type of gearbox would agree that getting the torque balance correct requires a detailed analysis effort plus several cycles of bench test/design modification.
If you compare it to the 53E main gear box, is it an order of magnitude more difficult or within the same order of magnitude in difficulty ... given the weight target?