A system for controlling the movement of an aircraft engine cowl door comprising: an actuator assembly including: a housing ; a screw shaft arranged at least partially within a hollow interior of the housing , the screw shaft being rotatable about an axis relative to the housing ; a transmission system coupled to the screw shaft to impart rotation to the screw shaft about the axis; a nut engaged with the screw shaft ; a piston rod having a first end and a second end and a hollow interior, the first end being connected to the nut ; a rod end mounted to the second end of the piston rod for connecting the nut to the cowl door of the engine, wherein the nut is translatable relative to the screw shaft to transition the cowl door between a first position and a second position; and a lost motion device coupled to the piston rod and disposed within the hollow interior of the piston rod, the lost motion device comprising a compression coil spring arranged within the hollow interior of the piston rod and between an inwardly extending flange of the piston rod and the rod end , wherein the rod end is slidably mounted in the hollow piston rod, the lost motion device being operable to absorb mechanical vibration of the cowl door and thermal expansion of the engine casing. an actuator assembly including: a housing ; a screw shaft arranged at least partially within a hollow interior of the housing , the screw shaft being rotatable about an axis relative to the housing ; a transmission system coupled to the screw shaft to impart rotation to the screw shaft about the axis; a nut engaged with the screw shaft ; a piston rod having a first end and a second end and a hollow interior, the first end being connected to the nut ; a rod end mounted to the second end of the piston rod for connecting the nut to the cowl door of the engine, wherein the nut is translatable relative to the screw shaft to transition the cowl door between a first position and a second position; and a lost motion device coupled to the piston rod and disposed within the hollow interior of the piston rod, the lost motion device comprising a compression coil spring arranged within the hollow interior of the piston rod and between an inwardly extending flange of the piston rod and the rod end , wherein the rod end is slidably mounted in the hollow piston rod, the lost motion device being operable to absorb mechanical vibration of the cowl door and thermal expansion of the engine casing. a housing ; a screw shaft arranged at least partially within a hollow interior of the housing , the screw shaft being rotatable about an axis relative to the housing ; a transmission system coupled to the screw shaft to impart rotation to the screw shaft about the axis; a nut engaged with the screw shaft ; a piston rod having a first end and a second end and a hollow interior, the first end being connected to the nut ; a rod end mounted to the second end of the piston rod for connecting the nut to the cowl door of the engine, wherein the nut is translatable relative to the screw shaft to transition the cowl door between a first position and a second position; and a lost motion device coupled to the piston rod and disposed within the hollow interior of the piston rod, the lost motion device comprising a compression coil spring arranged within the hollow interior of the piston rod and between an inwardly extending flange of the piston rod and the rod end , wherein the rod end is slidably mounted in the hollow piston rod, the lost motion device being operable to absorb mechanical vibration of the cowl door and thermal expansion of the engine casing. <EOS>