TRIUMPH GROUP
Balance of Power The latest innovation in force balance design from Triumph’s Aerospace System group is the Six Component High Capacity Force (Hi-Cap) Balance. The Hi-Cap Balance measures forces in the normal and side planes, rolling moment and axial force. Pitch and yaw are resolved from the outputs of the normal and side elements. Dennis Booth gives the background to this development The successful features of its predecessor, internal flexure design and axial element, were incorporated into the Hi-Cap design with only minor user interface changes to the outer geometry. The internal workings of the balance were redesigned to allow for a dramatic increase in load capacity while reducing the deflection and maintaining the diameter. A redesign in gauge layout creates greater accuracy and closer matched output for all components, drastically reducing output tradeoffs in the design phase. Utilizing the Automatic Balance Calibration System, the Hi-Cap Balance excels in both the 3 Force 3 Moment Format and when defined in a 5 Force 1 Moment Format. Although overall load capacity is increased, it has not adversely affected the performance at the low-end range of the operating envelope. Hi-Cap balance The Automatic Balance Calibration System (ABCS) is calibrations include multiple calibrations able to apply any single component or combination across the load envelope with a tailored of loads to fully characterize six component balances smaller-load envelope calibration to riUMph’s Force Measurement systems group (fMs) increase low-end resolution performance for alternative testing embodies a legacy of decades of experience forged into applications. The ability to redefine the allowable loads based on test cutting-edge measurement devices. force-type balance requirements enable a single balance, rather than the usual multiple designs have continued to evolve to meet the complex balances, to fill the requirements of the test. needs of the aerospace industry. The Hi-Cap’s rugged precision was utilized in both continuous-flow Previous force type balances design, dating back and blow-down facilities including government, 50 years, suffered load limitations. These commercial, foreign and domestic. Many have limitations occurred as a result of all applied commented on its “stellar performance” from loads acting on the load sensing elements tests on the next generation of aircraft. and the deflection of the internal workings. Having reached design maturity in a The Hi Cap Balance reduces the few short years, the Hi-Cap The MC-44h-1.750 Balance is a compact version of the hi-Cap series. The short length and high loads are suited for testing launch vehicles magnitude of the stress from loads Balance is a proven and reliable in all directions industry tool. It is the except the primary ideal balance load direction. The for meeting deflections of this the demanding type of balance are wind tunnel test The MC-60h-2.50 hi-Cap Balance has a larger frame for testing models with increased load ranges of low when compared requirements of today and the Normal and Roll. The load range is also adjustable to meet test requirements. with conventional single piece future. Anticipating the needs of and other force type balances the future aerospace industry at the same load capacity and has led the FMS team to diameter. examine new systems, The new-generation Hi sensors, and other leadingThe MC-60h-2.00 hi-Cap Balance is well suited for testing a wide variety of aero models. The load Cap design offered challenges edge approaches to balance range is adjustable to meet changing test requirements to successfully incorporate technology. these changes without sacrificing the state-of-the-art high level of CONTACT performance of the existing design (the Flexured Force Balance), Contact Dennis Booth, Triumph Aerospace Systems while maintaining the ability to fabricate and instrument the balance. E-mail: drbooth@triumphgroup.com
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