Structural integrity field

The structural integrity field (abbreviated SIF) was a force field system on a starship that strengthened the hull and structure to better withstand the stresses of warp travel.

A starship's hull would actually sag in a planetary gravity well without the SIF. (' reference: ')

In an alternate version of 2374, USS Voyager'' (NCC-74656) was forced to go to warp with the SIF inoperative due to battle damage, in order to escape the Krenim temporal weapon ship. The exterior hull began to disintegrate under the stress.''

In 2409, USS Bajor became trapped in the Nightmare Anomaly, and the stress began to wear down the SIF and cause damage to the hull before the ship was able to escape.

In 2410, USS Bajor entered the gravity well of the black hole NGC-21997 to rescue the crew of RBS, using her SIF to withstand the gravitational stress. Verda was subsequently destroyed by the black hole when her SIF failed.