Avion/AvTask – Our Story

• Avion, Inc incorporated in 1992 as an engineering support contractor for Army aviation. One of the first contracts awarded to Avion was to collect and organize data on the structural condition of CH-47 aircraft as they returned from Desert Storm. We became aware that an extraordinary number of man hours and test flights were required to track and balance the rotor system.
• Our original hypothesis was the operations in the harsh desert environment had caused a migration of the blade’s chord center of gravity. A method for testing this hypothesis was required.

• Avion took on the challenge; creating a static balance fixture based upon three point weight-and-balance theory. The Avion system was tested at both Ft. Campbell and Ft. Carson. Data showed that a shift in center of gravity did occur; however the shift was predominately in the span direction, not chord wise. The Avion prototype system was sold in limited quantities, but led to a vastly improved system which was used for the CH-47 and all of the Army’s Force Mod aircraft. It is used today on over 30 military and commercial aircraft. The improved balance fixture, the USBF, was sold at the field unit level and generated volumes of data regarding blade condition and changes in that condition with use.
• The field data highlighted a problem reported by Army units; CH-47 blades were becoming heavier with time in the field, and, over time, could not be balanced by simple removal of balance weights. We learned through reports of field results and experimentation at Avion/AvTask, that the problem was weight gain attributed to water intrusion.
• AvTask, the engineering and prototyping activity within Avion/AvTask created the “Magic Box” which reversed the environmental conditions that created the water intrusion. A production system was developed based on our prototype to hold 11 Chinook blades which could be dried to a Boeing-developed spec. The system introduced heating, cooling, evaporation, condensation, and changes in barometric pressure. The optimal mix of the weather-related conditions and the cycle time were determined through extensive testing.
• The Magic Box was used as the centerpiece of a process at AvTask. That led to Boeing Approval of the process and the inclusion of AvTask as the commercial supplier listed on the CH-47 Blade Overhaul QPL.