During a discussion during cruise today, my First Officer raised an insightful technical point regarding the Flydubai incident that I think got overlooked: the counterintuitive advantage of manual reversion.
In simulator training, pilots dread dual hydraulic failure. Without hydraulic assistance, the Boeing 737 reverts to mechanical cables and tabs. Control forces become extremely heavy, and aerodynamic response is sluggish—much like driving a heavy vehicle without power steering.
Yet, in this scenario, that sluggishness likely saved the airframe.
With both engines cut and hydraulic pressure lost, pulling back on the yoke required massive physical effort to achieve even marginal control surface deflection. When the untrained plumber hauled back on the controls, the aerodynamic response was dampened enough to arrest the steep dive without generating catastrophic G-forces.
Had hydraulic systems remained fully powered, an abrupt, panicked pull on the yoke could have easily overstressed the airframe, risking structural breakup.
Paradoxically, the engine shutdown that threatened the flight also enforced the mechanical damping needed to survive the recovery.
Food for thought 💭