The Ruth Mary Petry Papers contain information about Petry's experience as a member of the WASP during World War II and her postwar involvement in the Order of Fifinella, the official WASP organization. The collection spans from 1940 to 1991, and most of the materials are from 1944 and focus specifically on World War Two WASP activities. Document formats in this collection include: personal letters from 1943 to 1949, certificates and official papers from 1940 to 1945, newsletters, newspapers from the 1940's, photographs, WASP rosters, manuals, a copy of a transcript of a 1989 oral history interview conducted by Texas Woman's University, and artifacts.

Petry's letters discuss the daily duties and life of a WASP. Frequently she describes, in detail, training exercises, weather, planes, ferrying orders and cross country flights, life in the bunk, uniforms, flight classes, and cockpit procedures. Petry also discusses the deactivation of the WASP, which took place on 20 December 1944 in her personal correspondence with both family and fellow WASP. In a letter received by Petry from a fellow WASP stationed in Sioux Falls, South Dakota the dynamic between WASP and the service men who were stationed on base is described.

Petry remained active in WASP affairs postwar by joining the Order of Fifinella; the other half of the collection focuses on the corporation of the WASP/Order of Fifinella organization, the history of the Order of Fifinella, the campaign for gaining veteran status, and reunion information and WASP updates.