This Aerospace Recommended Practice (ARP) specifies the requirements of balancing machines that make them suitable for the subject class of work. It was developed for soft-bearing balancing machines but may also be used for hard-bearing machines until ARP4048 is issued for that type of machine. Particular not should be taken that this ARP examines only the capability of a balancing machine to indicate the correct amount of dynamic or static/couple unbalance in specified proving rotors. Such rotors are commonly used for testing balancing machines to provide precisely controlled and comparable test results. Further tests of a particular machine may be necessary to assess the capability to balance rotors of different weights and configurations, rotors with outboard c.g. and/or correction planes, and those with disturbance causing features, such as rotors subject blade scatter, windage, etc.
