Impulse generator

From Memory Alpha, the free Star Trek reference

The impulse generator is an integral part of the impulse drive of a of a number of different ship designs, such as Federation shuttlecraft and some Cardassian freighters.

The impulse generators of the type 15 shuttlepod Campbell went offline when the crew of the shuttlepod tried to land on a storm-ridden moon of Mab-Bu VI in 2368. (TNG: "Power Play")

When a network of artifical satellites attcked the runabout USS Yangtze Kiang while orbiting a penal moon in the Gamma Quadrant the impulse generator failed. (DS9: "Battle Lines")

A malfunction in the impulse generator was among the early theories for the cause of the destruction of the Cardassian freighter Bok'Nor in 2370. It was dismissed once evidence of sabotage was found. (DS9: "The Maquis, Part I")