Shift shields were a kind of shield protecting starships in space. During the Galactic Civil War, Dark Lord of the Sith Darth Vader captured and destroyed the CR90 corvette Tantive IV. He blamed the destruction of the corvette on the failure of its shift shields in order to hide his actions from the Imperial Senate.
Shift shields were a type of starship shield that protected against physical objects such as meteoroids. If the shields were overridden, the incoming objects could break the hull, causing atmospheric loss.
Darth Vader instucted Daine Jir to send a distress signal aboard the Tantive IV.
In 0 BBY, during the battle of Tatooine in the Galactic Civil War, the Star Destroyer Devastator pursued, captured, and destroyed the CR90 corvette Tantive IV, an Alderaanian diplomatic vessel. Dark Lord of the Sith Darth Vader instructed Imperial Commander Daine Jir to send a distress signal to indicate the failure of the Tantive IVs shift shields in a meteoroid shower in order to explain the destruction of the vessel to the Imperial Senate.
The first and only mention of shift shields was in the December 1976 novelization of Star Wars: Episode IV A New Hope, ghostwritten by Alan Dean Foster. The function of these shields was similar to particle shields or concussion shields, which were mentioned in later sources.
- Gundark's Fantastic Technology: Personal Gear