This is Luke's outfit as a starfighter pilot. In it he fought in the battle of Yavin, destroyed Imperial walkers on Hoth, and crash landed on Dagobah.
Luke Skywalker has five personas in the game, which are treated as different characters. Pilot Luke was introduced in version 1.0.
This version of Luke does not unlock any scenes. As a Rebel, he is actively chased off of any Imperial level.