"Obstacle clearance strategy allows the aircraft to maintain cruising altitude the longest, provides the least possible rate of descent and will result in the highest possible engine out cruising altitude for the conditions. In this procedure, maximum continuous thrust is set and (except in aircraft where AP & AT will maintain the required level of thrust and descent profile) the autothrottle disconnected. The speed target is adjusted to the best engine out speed and altitude is maintained while the speed slowly decays from the all engine cruising speed. When the target speed is achieved, a descent at maximum continuous power/thrust and the target airspeed is initiated. During the descent, speed is adjusted to maintain the best speed for the current altitude and the descent is continued until Drift Down altitude is reached."
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