HMCS Corner Brook, a long range hunter-killer Canadian submarine, is in dry dock undergoing a complete overhaul in Esquimalt.

The Victoria-class submarine is halfway through its retrofit, barely recognizable, shrouded in scaffolding and protective wrap.

Once completed, the sub will be outfitted with state-of-the-art technology and will better able to patrol Canadian coastlines.

CTV News was able to get a look at the project Monday, which is halfway to completion.

"Corner Brook will essentially be a brand new submarine," said Cmdr. Mike Mangin. "So this really puts the Victoria-class submarines at the cutting edge of submarine technology."

The upgrades include a new mast system and military satellite communications antenna.

Following the refit, the sub is estimated to be back in service for another 15 years. The work should be complete by early 2020.