The Starlancer Project or Operation Starlancer was a secret project created by the New Republic military to trick the Yuuzhan Vong.
The project consisted of four pipefighters (actually modified BTL Y-wing starfighters), three of which would form a triangle, with the fourth in the middle of the triangle. The three triangle fighters would then channel energy into the fourth, which would fire a supposed hyperspace laser focused by a Yuuzhan Vong lambent crystal.
It was meant to be used against the worldship over Coruscant. Moments after striking, the beam was swallowed by a dovin basal. Two attempts were made by the Yuuzhan Vong to destroy the weapon's lambent crystal which was used to focus the weapon's laser. Both attempts failed. The weapon met its end at the Second Battle of Borleias, when squadrons of coralskippers attacked the pipefighters.
The entire project, however, was a ruse designed to keep the Yuuzhan Vong off balance. The New Republic was thus able to convince the Yuuzhan Vong to divert resources towards destroying the ersatz superweapon rather than concentrating on other military objectives.
- The Complete Star Wars Encyclopedia