Real Tonga Airlines' Jetstream plane has run in to problems on a flight from Vava'u to the main island, Tongatapu.
The infrastructure minister, 'Etuate Lavulavu, told Radio Tonga the aircraft has been detained and grounded until a complete incident report is submitted to the ministry.
Mr Lavulavu says one of the computerised engines overheated mid-flight and had to be turned off. The plane landed safely with one engine.
Real Tonga has been embroiled in diplomatic controversy after New Zealand issued a travel advisory against flying an MA-60 plane gifted to the airline from China.