A Jetstar A320 aircraft was forced to return to Auckland Airport, after a clipboard was left on the plane's engine cowl by a ground handler.
Flight JQ 202 took off from Auckland, bound for Sydney, on Saturday morning, when a small amount of debris could be seen coming out of the back of an engine.
The pilots returned to Auckland as a precaution and carried out a normal landing.
"An inspection of the engine showed some minor repairs were required," a Jetstar spokesman said.
"The repairs were completed by our engineering team and the aircraft returned to service on Saturday afternoon.
"We have commenced a full investigation and are working with our supplier to understand how this happened."
No one was injured in the incident.