Lt. Cdr. Zachary Lansdowne (December 1, 1888 – September 3, 1925) was a 1909 graduate of the United States Naval Academy and one of the first U.S. Navy officers trained in lighter-than-air aviation.

Lansdowne trained with the crew of the British airship R-34 and became the first American to cross the Atlantic nonstop by air as the American naval observer aboard R-34″²s 1919 transatlantic flight.

After service as a White House aide, Lansdowne was the Assistant Naval Attache in Germany in 1922-1923, where was involved with the negotiations for the construction of the LZ-126, which became the ZR-3 U.S.S. Los Angeles.

Lansdowne’s energetic personality and fierce devotion to lighter-than-air aviation would drive the operations of U.S.S. Shenandoah and determine its future.  Although Shenandoah was too small to conduct extended operations at sea (since the ship’s relatively small gas capacity limited its ability to carry fuel, and therefore its range),  Lansdowne was determined to demonstrate the potential of the rigid airship as a naval scouting vessel, and to show that large airships could operate alongside the surface fleet.

Lansdowne was killed in the Shenandoah crash on September 3, 1925. He had warned the naval authorities that his ship was not structurally suited for operation in midwest thunderstorms but his appeals for a postponement of the flight were overruled.