Chinese police detained the passenger and released a statement.
Airport employees said she appeared to be about 80, and she had "limited mobility and was accompanied by her husband, daughter and son-in-law", The Straits Times reported.
Qiu was confirmed to have no previous criminal records and no history of mental illness.
Her "good luck" ritual prompted concerned passengers to alert airline staff, who conducted a full examination of the engine and evacuated 150 passengers. "According to Qiu's neighbour, Qiu believes in Buddhism", the police said.
The airline subsequently urged fliers to obey civil aviation rules and avoid behavior that could put the safety of passengers at risk.
A woman has been placed under investigation in Shanghai city for flipping coins into an aircraft engine to "pray for safety".