Please help me better understand what causes a jet airliner (such as the Boeing 737-500) to roll toward the "weaker" engine when power is reduced on one side.
Such as in the situations featured in 6:36 through 7:54 and 21:50 through 23:20 in this "Mentour Pilot" YouTube video about the January 9, 2021 crash of Sriwijaya flight 182. (Links to set to start at segments: 1, 2.)
My specific questions center around how the yaw damper affects the situation, compared to what we'd see in a twin-engine airplane with no yaw damper.
Is the situation simply that the asymmetrical thrust creates a yaw torque that directly leads to the aircraft flying in a slipping condition, as would be measured by a yaw string at the nose? Which then creates a roll torque via aerodynamic coupling between slip and roll, due to sweep and dihedral? Is this the dominant source of the roll torque toward the weaker engine?
How is the yaw damper responding to the asymmetrical thrust condition? Is it attempting to maintain a zero-sideslip condition, as would be measured by a yaw string? Or as would be measured by a slip-skid ball (inclinometer)? But is unable to do so? Why is it unable to do so?
Or is it likely that the sideforce from the deflected rudder, acting high above the CG of the aircraft, is in fact the dominant source of the roll torque toward the weaker engine? (It seems that this is what we might expect if the yaw damper was in fact able to maintain a zero-sideslip condition, as measured either by a yaw string, or by the slip-skid ball.)
Or alternatively, could the effect of the jetwash on the airflow near the wing be the dominant source of the roll torque toward the weaker engine?