K Class Blimp - Airship Designations

Airship Designations

During the life of the K-class airship, the U.S. Navy used three different designation systems. From 1922 through World War II, the Navy used a four character designator. The K-class blimps were designated ZNP-K where the "Z" signified lighter-than-air; "N" denoted non-rigid; "P" denoted a patrol mission; and "K" denoted the type or class of airship.

In April 1947, the General Board of the U.S. Navy modified the designation system for airships. The second character of the designator was dropped as the Board dropped the code for rigid airships so that the "N" for non-rigid was no longer needed. The designation for the K-class blimps then became ZPK.

In April 1954, the designation system for lighter-than-air airships was further modified so that it conformed to the designation system for heavier-than-air aircraft. By this time the ZPK blimps had been retired from service and only the later version K-Class blimps were in service. Under the 1954 system the ZP2K blimp became the ZSG-2, the ZP3K became the ZSG-3, the ZP4K became the ZSG-4, and the ZP5K became the ZS2G-1. In new designation system, the "Z" signified lighter-than-air; the "S" was the type denoting an anti-submarine warfare mission; the numeral (i.e., "2") was the model; and the "G" was for Goodyear, the manufacturer’s letter in the Navy's designation system. The final numeral denoted the series of the vehicle within the type/model.