In the ole ATPL(H) material Hydraulic Lock is described as different to Jack Stall- which if I remember correctly is a hydraulic force overload. Hydraulic Lock as I understood it from the ATPL(H) studies is a failure (design or mechanical) in which the hydraulic pressure gets around the back of the relevant actuator(s) and the controls become hydraulically 'locked'.
Definition of mourn - feel or show sorrow for the death of (someone), typically by following conventions such as the wearing of black clothes Definition of mourn - feel or show sorrow for the death of (someone), typically by following conventions such as the wearing of black clothes dictionary thesaurus
Rue comes from the Old English word hreowan, meaning to make sorry, and rue can still sum up a lot of sorrow in one small syllable. Rue is a modern verb that often looks back on the past. Shakespeare made famous the phrase rue the day, meaning you bitterly regret a moment.