Echo 206

Echo 206 was a Pelican dropship attached to the in 2552.

Battle of Installation 04
When that vessel crashed on Installation 04, this dropship was spared from destruction by its pilot, who launched it as the Autumn descended into the atmosphere.

The vessel then met up with other human survivors at Alpha Base where it was assigned to run supply missions from the Autumn to Alpha Base, along with Pelican Echo 136.

This Pelican was most likely piloted by Warrant Officer Polaski and although the designation is not mentioned in Halo: First Strike, there is no mention of it being destroyed in Halo: The Flood so this is the best candidate to be the Pelican in the book.