US Patent 8973861 Tetra-propeller aircraft

Described herein is a vertical take-off and landing aircraft comprising: an upper enclosure comprising a first upper arm and a second upper arm; a lower enclosure comprising a first lower arm and a second lower arm; wherein the first upper arm and the first lower arm comprise a first upper buckle and a first lower buckle, respectively; wherein the second upper arm and the second lower arm comprise a second upper buckle and a second lower buckle, respectively; wherein the first upper buckle engages the first lower buckle and the second upper buckle engages the second lower buckle, thereby securing the upper enclosure to the lower enclosure.