Name: Sienar Test Facility 73
Type: Testing facility
Location: 73
Affiliation: Sienar Fleet Systems, Galactic Empire

Description: Sienar Test Facility 73 was a Sienar Fleet Systems testing facility on the planet 73. In 4 BBY, Cassian Andor stole a TIE Avenger prototype from the facility.

Description
Sienar Test Facility 73 was a testing facility operated by Sienar Fleet Systems, located on the snowy planet 73; one of the various numerically designated planets owned by the company. The facility consisted of a series of connected structures and contained at least one commissary and at least three hangars.

History
By 4 BBY, the facility was operational, with its own workforce and a dedicated defense battalion consisting of stormtroopers, range troopers and at least two TIE Advanced v1s. In 4 BBY, its workforce included Niya, her coworker, and her supervisor. During that year, Niya assisted Cassian Andor, a rebel operative posing as a Sienar test pilot, in stealing the facility's TIE Avenger prototype from one of its hangars. During the theft, Andor damaged the hangar using the TIE’s weapon systems.