Lieutenant Commander Zachary Lansdowne, USN (December 1, 1888 – September 3, 1925) was a United States Navy officer and early Naval aviator who contributed to the development of the Navy's first lighter-than-air craft. He earned the Navy Cross for his participation in the first transoceanic airship flight while assigned to the British R34 in 1919. He later commanded the USS Shenandoah (ZR-1), which was the first rigid airship to complete a flight across North America. He was killed in the crash of the Shenandoah.