Apollo 11 Mission, first to land men "on the moon", documentary video showing launch details on the ground. Much revealed I have never before heard of, such as enormous amounts of water poured over launch pad to cool it. The four structural arms seen intersecting the bottom of the craft are "hold-downs" which prevent lift-off until a certain amount of upward thrust is achieved, something like a few million pounds! This keeps the ship from tilting sidewise as it slowly lifts off. IOW, a great amount of thrust is already present when the arms retract, swinging into the vertical position allowing the vehicle to lift slowly upwards. The vehicle was 360 feet tall, and generated 7,600,000 lbs.of thrust at lift-off, while weighing just over 6 million pounds. The power generated equaled that of 85 Hoover Dams!. Note the immense amount of heat imparted to the launch structures after the vehicle has cleared it, fires burning as insulating materials were spread over them and themselves burned instead. This effort was beyond a doubt, in my mind one of the most complex successful Engineering projects ever undertaken. See NASA article for more details: https://www.nasa.gov/centers/johnso...rn V rocket was,weight of about 400 elephants.