The captain's yacht of the Sovereign-class Enterprise-E, a sleek auxiliary craft docked beneath the saucer, which Picard and his officers take to the Ba'ku planet in Star Trek: Insurrection.
The Cousteau is the captain's yacht of the USS Enterprise-E, seen in the 1998 film Star Trek: Insurrection. It sits flush in the underside of the saucer section and detaches for independent flight. The craft is named after the French ocean explorer Jacques Cousteau.
In 2375 Picard and his senior officers fly the yacht down to the Ba'ku planet, since the metaphasic radiation of the planet's rings and the surrounding Briar Patch make ordinary operations difficult. It is their means of reaching the surface while Picard uncovers the plan by the Son'a and Admiral Dougherty to remove the Ba'ku in secret.
The idea of a captain's yacht had existed since the design of the Enterprise-D, whose own yacht was never shown in use. The Cousteau was the first to be seen in flight.