Testing of Guided Parafoil Cargo Delivery Systems

Abstract

*This paper concentrates on presenting techniques and procedures used during airdrop testing and verification of guided parafoil cargo delivery systems. Included in this paper are results of guided parafoil airdrops and ground tests conducted at U.S. Army Yuma Proving Ground (YPG). Additionally, techniques used in the data collection are presented in conjunction with a discussion of reduction techniques for comparing on-board system navigation data to instrumentation data for both the airdrop and static ground tests. Two main topics guide this paper. They both relate to parafoil airdrop systems with navigation capabilities. The first topic focuses on testing results from airdrop and ground tests conducted at YPG. The second topic covers techniques for data collection, system position verification, and instrumentation setup and utilization. After conducting multiple airdrops and several ground tests with different guided parafoil systems, the test data has been gathered and is presented to show the procedures and techniques used when addressing the individual system’s capabilities. Collection of data logged both by the guided parafoil system and from a truth-source was critical when looking at a system’s performance and capabilities. The deviation between the system’s logged flight data and the truth-source data allows the tester to evaluate the system’s flight performance including its glide ratio, turning rates, and landing accuracy. When developing techniques for placing instrumentation on guided systems, the differences in navigation systems on each guided parafoil system must be taken into account. Typical navigation systems integrated in a guided system include Global Positioning System (GPS) and/or Inertial Navigation System (INS). The system specific navigation system, allows the system to operate autonomously, but it is important that instrumentation used during testing of these systems be independent of the system specific navigation system, to evaluate true system performance. A steerable gliding parachute capable of autonomous navigation by means of GPS and/or INS is a desirable capability with many airdrop applications. Current applications in the airdrop community include a means to deliver critical payloads to the ground from significant horizontal and vertical offsets. The goal of the tester in evaluating these systems is to provide insight into the capabilities each guided system possesses. By using good data acquisition techniques and evaluating the system’s flight performance, the performance, reliability, and accuracy of the system is improved.