Optimized parachute recovery systems for remote piloted aerial systems

The new RPAS (remotely piloted aerial systems) are mostly video cameras with wings whose ownership isn't enshrined in any constitution. Rulers are rushing to do regulate the lack of safety and accountability for RPAS. In Italy ENAC (aviation authority) legislated against random acts of stupidity and probable failures. For the current year of 2015, there is a forecast to sell $1bn worth of RPAS product. For these reasons the installation of RPS (Recovery Parachute System) on commercial RPAS is particularly interesting. A few RPS manufacturers have manufactured specific RPS systems for "drones" both rotary and fixed wing. However, these systems are designed with the same criteria of manned aerial vehicle. This paper demonstrates that the design criteria of RPAS are sensibly different from other applications. In particular the rate of descent during recovery should be reduced from 6m/s to 2m/s. This fact poses new challenges in parachute design. In fact RPS mass depends on parachute diameter that increases with low descent rates. This paper demonstrates that it is possible to design effectively RPS for RPAS up to 80kg by using nonwoven fabric in parachutes. In this way the RPS mass is a small fraction of the RPAS one. Deployment systems are not a problem for RPAS since masses are extremely small and the power necessity are accordingly limited.