what is the purpose of a flying buttress
Flying buttress The defining, functional characteristic of a flying buttress is that it is not in contact with the wall it supports, like a traditional buttress, and so transmits the lateral forces across the span of intervening space between the wall and the pier. To provide lateral support, flying-buttress systems are composed of two parts: (i) a massive pier, a vertical block of masonry situated away from the building wall, and (ii) an arch that bridges the span between the pier and the wall — either a segmental arch or a quadrant arch — the flyer of the flying buttress.[2]
Helicopter The earliest references for vertical flight came from China. Since around 400 BC,[8] Chinese children have played with bamboo flying toys (or Chinese top).[9][10][11] This bamboo-copter is spun by rolling a stick attached to a rotor. The spinning creates lift, and the toy flies when released.[8] The 4th-century AD Daoist book Baopuzi by Ge Hong (抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft.[12]