An aircraft , comprising: a fuselage ; at least one wing extending from the fuselage ; at least one horizontal stabilizer extending from the fuselage ; and a vertical stabilizer extending from the fuselage and including a composite panel , wherein the composite panel includes a core structure and at least one composite skin extending across an external surface of the core structure , wherein the core structure comprises: a first side ; a second side ; and a connecting region that interconnects an upper portion of the first side with an upper portion of the second side ; wherein: (i) the first side , the second side , and the connecting region at least partially define an antenna housing defining a housing volume configured to contain an aircraft antenna of the aircraft ; (ii) the first side , the second side , and the connecting region together define an electromagnetic wave transmission region configured to permit electromagnetic waves to pass therethrough; (iii) the electromagnetic wave transmission region defines a plurality of kite-shaped voids arranged in a repeating pattern; (iv) the plurality of kite-shaped voids is bounded by a corresponding plurality of walls ; and (v) at least 10% of the corresponding plurality of walls extends at least substantially perpendicular to a surface (122/124) that bounds the electromagnetic wave transmission region . a fuselage ; at least one wing extending from the fuselage ; at least one horizontal stabilizer extending from the fuselage ; and a vertical stabilizer extending from the fuselage and including a composite panel , wherein the composite panel includes a core structure and at least one composite skin extending across an external surface of the core structure , wherein the core structure comprises: a first side ; a second side ; and a connecting region that interconnects an upper portion of the first side with an upper portion of the second side ; a first side ; a second side ; and a connecting region that interconnects an upper portion of the first side with an upper portion of the second side ; wherein: (i) the first side , the second side , and the connecting region at least partially define an antenna housing defining a housing volume configured to contain an aircraft antenna of the aircraft ; (ii) the first side , the second side , and the connecting region together define an electromagnetic wave transmission region configured to permit electromagnetic waves to pass therethrough; (iii) the electromagnetic wave transmission region defines a plurality of kite-shaped voids arranged in a repeating pattern; (iv) the plurality of kite-shaped voids is bounded by a corresponding plurality of walls ; and (v) at least 10% of the corresponding plurality of walls extends at least substantially perpendicular to a surface (122/124) that bounds the electromagnetic wave transmission region . (i) the first side , the second side , and the connecting region at least partially define an antenna housing defining a housing volume configured to contain an aircraft antenna of the aircraft ; (ii) the first side , the second side , and the connecting region together define an electromagnetic wave transmission region configured to permit electromagnetic waves to pass therethrough; (iii) the electromagnetic wave transmission region defines a plurality of kite-shaped voids arranged in a repeating pattern; (iv) the plurality of kite-shaped voids is bounded by a corresponding plurality of walls ; and (v) at least 10% of the corresponding plurality of walls extends at least substantially perpendicular to a surface (122/124) that bounds the electromagnetic wave transmission region . <EOS>