TAIPEI (Taiwan News) – An Indigenous Defense Fighter (IDF) jet returned to base after failing to drop its bombs, reports said Tuesday (Sept. 10).

One of the aircraft based in Tainan went out for a bombing exercise with two Mark 82 bombs on Monday (Sept. 9). However, military fans noticed it returned to base with the two bombs intact, the Liberty Times reported.

As soon as the jet landed, it was surrounded by a bomb disposal unit, the report said. According to the military, an investigation will focus on a possible failure by the bomb-dropping mechanism.

The plane was supposed to drop the bombs and hit a prepared target in Penghu. Because the plan did not work out, the pilot returned to base, but a firefighting unit and the bomb disposal team were on standby, the report said.

Taiwan’s 129 IDF jets, based in Taichung and Tainan, have been in service since 1992. The planes were included in two upgrade programs, adding digital elements and electronic counter-countermeasure (ECCM) radar capabilities.