What is a box spar? I know the spar is a structural element of the wing, it carries majority of the load. Does box refer to the shape? - Quora
![Construction of wing box of a commercial aircraft. 1 – center spar, 2 –... | Download Scientific Diagram Construction of wing box of a commercial aircraft. 1 – center spar, 2 –... | Download Scientific Diagram](https://www.researchgate.net/publication/244989196/figure/fig1/AS:298446381699075@1448166570680/Construction-of-wing-box-of-a-commercial-aircraft-1-center-spar-2-front-spar-3.png)
Construction of wing box of a commercial aircraft. 1 – center spar, 2 –... | Download Scientific Diagram
![Subaru Corporation Completes First Boeing 777X Center Wing Section | NewsRelease | Subaru Corporation Subaru Corporation Completes First Boeing 777X Center Wing Section | NewsRelease | Subaru Corporation](https://www.subaru.co.jp/press/file/uploads/news/2018_0209_5-1.jpg)
Subaru Corporation Completes First Boeing 777X Center Wing Section | NewsRelease | Subaru Corporation
![Parts of wing-to-fuselage assembly for Airbus A350-900. Outer wing box... | Download Scientific Diagram Parts of wing-to-fuselage assembly for Airbus A350-900. Outer wing box... | Download Scientific Diagram](https://www.researchgate.net/publication/339748858/figure/fig2/AS:866144839811083@1583516430679/Parts-of-wing-to-fuselage-assembly-for-Airbus-A350-900-Outer-wing-box-left-and-central.png)