A piston assembly for an aircraft, comprising: a piston housing ; a piston housing fluid port formed in the piston housing for supplying fluid to and removing fluid from the piston housing ; a piston shaft disposed within the piston housing , wherein the piston shaft is configured for translation in either forward or aft directions when fluid is respectively supplied to or removed from the piston housing ; a screw shaft disposed within the piston housing , wherein the screw shaft includes a first gear that is adapted to rotate without translation in either the forward or aft directions while the piston shaft translates in either the forward or aft directions, wherein the screw and piston shafts are configured as a screw-nut pair; and a slider disposed within the piston housing , wherein the slider includes a second gear , and wherein the slider is configured for translation in either the forward or aft directions without rotation due to pressure within the piston housing , wherein: the slider is adapted to move between a first position and a second position, wherein, in the first position, the first gear and the second gear are separated from one another to allow the piston shaft to translate in the forward direction or the aft direction; and characterized by the first gear and the second gear being dog gears that extend radially toward one another, and in the second position, the second gear surrounds and engages the first gear so that the first and second gears are engaged with one another and the piston shaft is prevented from translating in the forward or aft directions. a piston housing ; a piston housing fluid port formed in the piston housing for supplying fluid to and removing fluid from the piston housing ; a piston shaft disposed within the piston housing , wherein the piston shaft is configured for translation in either forward or aft directions when fluid is respectively supplied to or removed from the piston housing ; a screw shaft disposed within the piston housing , wherein the screw shaft includes a first gear that is adapted to rotate without translation in either the forward or aft directions while the piston shaft translates in either the forward or aft directions, wherein the screw and piston shafts are configured as a screw-nut pair; and a slider disposed within the piston housing , wherein the slider includes a second gear , and wherein the slider is configured for translation in either the forward or aft directions without rotation due to pressure within the piston housing , wherein: the slider is adapted to move between a first position and a second position, wherein, in the first position, the first gear and the second gear are separated from one another to allow the piston shaft to translate in the forward direction or the aft direction; and characterized by the first gear and the second gear being dog gears that extend radially toward one another, and in the second position, the second gear surrounds and engages the first gear so that the first and second gears are engaged with one another and the piston shaft is prevented from translating in the forward or aft directions. the slider is adapted to move between a first position and a second position, wherein, in the first position, the first gear and the second gear are separated from one another to allow the piston shaft to translate in the forward direction or the aft direction; and characterized by the first gear and the second gear being dog gears that extend radially toward one another, and in the second position, the second gear surrounds and engages the first gear so that the first and second gears are engaged with one another and the piston shaft is prevented from translating in the forward or aft directions. <EOS>