The spares calculator: a visual aid to provisioning

Logisticians at the Westinghouse Electronic Systems Group prepared a visual aid for their customers in the form of a spares calculator. The calculator portrays required spares quantities based upon the customer's required level of protection. The calculator is appropriate for users of a variety of commercial and defense products. Selected as most appropriate to the needs of the provisioner was a moving-scale device with numerical values appearing in an open window. For compactness, a circular slide rule 8 in. in diameter was selected. The Gothic font bolt black-on-white makes the device easily readable.<>