A team of 12 graduate students from the Georgia Institute of Technology’s Daniel Guggenheim School of Aerospace Engineering used Abaqus while designing their entry in the American Helicopter Society (AHS) International’s 2009 Annual Student Design Competition. The competition, which challenges students to design a rotary wing aircraft that meets specified requirements, provides a practical exercise for engineering students at accredited colleges and universities while promoting student interest in flight technology.

Historically, rotary wing flight has been a trade between hover performance and forward flight speed. The search for an alternative drive that is capable of bridging this gap is one of the next frontiers of current rotorcraft aviation research. The design goal was to fulfill the Request For Proposal (RFP) of this design competition and bridge the gap of high speed forward flight with hover efficiency. Previous attempts to build fast helicopters have resulted in significant degradations in at least one common design parameter whether noise, hover performance, controllability, or operational cost.

Gear stress was implemented using Catia gear assembly and then analyzed in SIMULIA. The test was done at max power plus an additional 20% factor of safety. In this analysis the entire gear was able to be tested including the shaft connection points as opposed to the face and tooth stress analysis done above. These results showed that all gears were within allowable stress tolerances designated by AMGA.

 As the design phase gets to the final iteration, a finite element model is developed in Abaqus for Catia to verify if the structure is going to be able to perform certain maneuvers and satisfy the requirements from 14 CFR – Part 29 (subpart c). The finite element model should be able to withstand any critical condition with the proper factor of safety, which is define as the yield of the material over the maximum stress. A factor of safety of 1.5 is set as a constraint to optimize the structure. Based on the accuracy from first assumptions constructing the CATIA model, the number of iterations would vary from results of the FEM. However, since the CATIA model is parametric, this updates are perform almost instantly. Static loads are applied in different areas as seen in the figure , the main loads are applied from the hub and blades, transmission, engines and rear propfan since they will influence the primary structure. Loads applied were 18,512N for the hub and blades, 7,879N for the transmission, 3,332N for both engines and 3,400N for the rear propfan.