Aerodynamic efficiency enhancements for parachutes
The performances of manoeuvrable parachute-like textile wing structures available in the leisure market have been constantly improving. With a drag instead of a simple round canopy, parafoils became more and more interesting for commercial use in emergency aircraft recovery systems and the recovery of space equipment. In addition, such aerial delivery systems are often called to support humanitarian assistance operations. Challenged by the need for greater steerability and highly controlled descent rate, the FASTWing project sought to develop a self navigated gliding system for reliable and precise delivery of heavy loads. Under the coordination of Autoflug GmbH, research was directed at demonstrating that the stabilisation and reefing systems can be designed in a robust manner to permit practical deployment. To this end, model-scale wind tunnel tests were required to predict real size parafoil behaviour. Software tools were adapted and employed for aerodynamic performance evaluation and development in accordance with the preliminary design specifications. One of these is a sophisticated modelling tool that allows analysis of the flight mechanics details related to the canopy deployment. Based on the results from the model-scale technology demonstrator, a series of full-scaled qualification trials of the parachute system was performed by means of a payload dummy. In a next step remote controlled and fully autonomous controlled flights to a preprogrammed point were performed to validate functionality of the reefing system. The reefing system controls the inflation, and ultimately the speed and size of the parafoil. The results obtained with a dummy payload ranging from 1100kgr to 3200kgr showed a glide ratio greater than 4, a stable flight and high steering performance of the parafoil. The opening of the parafoil demonstrated reliability and the acceleration measurements were in good agreement with the simulations. Collaboration is sought with designers and/or manufacturers of parafoils and similar equipement for further verification of the new technology's compatibility in different fields.
