Acoustic emission testing (AE) was employed in this research to monito
r sound indications emanating from a specially designed and built gear
box. Various types of failures were purposely induced, simulating the
possible ''wear and tear'' conditions that a gearbox may undergo duri
ng its useful life. Results obtained at different speeds were plotted
against causes of failure. Subsequent analysis revealed the importance
of correlating AE results with known failures. The technique develope
d for early failure diagnosis has the potential of utilizing AE as a t
ool for predictive maintenance.