X hui-hêng-ki (X-plane) sī Bí-kok 1 hē-lia̍t ê hui-hêng-ki, bo̍k-tek sī beh chhì-giām sin ki-su̍t, lāi-té mā pau-hâm chi̍t-koá hoé-chìⁿ. Tī khai-hoat ê sî, lóng pó-chhî kah chin pì-bi̍t.

Bell X-1