International audienceThe paper looks back on the 1974 Specialists' Meeting on Rotorcraft Dynamics and the paper on Loads Comparison, and reflects broadly on the ensuing 40 years of aeromechanics R&D and the changes that have taken place. How the 1974 Specialists' Meeting came about and the process of how the Loads Comparison effort was initiated and organized is described, involving as it did, a cooperative effort of disparate industry analysts and government researchers. How these events influenced emerging Army rotorcraft R&D in the Ames environment, and the birth of the AHS San Francisco Bay Area chapter are recalled. To bridge the 40-year span of loads prediction, then and now, new results from today's evolved codes are compared with the original 1974 results. Modern results from RCAS, UMARC, along with CFD/CSD results from the HELIOS/RCAS and GT-Hybrid/DYMORE are presented. Suggestions are offered to address rotorcraft aeromechanics R&D in the future. * Preface The theme of the Fifth Decennial AHS Aeromechanics Specialists' Conference is " Current Challenges and Future Directions in Rotorcraft Aeromechanics. " As we aim toward these challenges and plan future research it is appropriate to look back on the origins of this unique series of five meetings and conferences. Although the technical environment was quite different and the rotorcraft world was of another era, today's challenges trace back to that time. Thus we may draw insight from past approaches and results therefrom and planners of today's research may perhaps benefit from understanding past approaches and lessons learned in the intervening four decades
