However, defects can occur at any time due to the aircraft's operating environment. They affect the performance of the aircraft and are characteristically unique, requiring individual solutions for each instance. Aircraft wings, engines and fuselage are most susceptible to damage on ground (by service and maintenance equipment and fixtures) and in air (by foreign objects, birds, lightning strikes or similar acts of nature). Consequently, unscheduled maintenance becomes necessary to replace defective components and ensure safety, reliability and airworthiness.

The AMOS project focuses on several key Direct Energy Deposition (DED) Additive Manufacturing (AM) processes. DED systems offer flexible and have great potential to be used as cost-effective and efficient repairing and re-manufacturing scenarios for aerospace components such as turbine blades and landing gears. Damaged components can be repaired (on-demand) and material lost in service can also be re-deposited to restore the component to its original shape. This approach has the potential to reduce lead times, costs, material waste and extend the service life of damaged or worn components.