FLC TAXIES OUT FOR TKOF WITH THE PROP BRAKE ON.

Narrative

ACFT TYPE; ATR 42 SCHEDULED DEP FROM LIHUE; HI. 1) WE WERE CLRED TO START #2 ENG; AFTER START WE WERE ASKED AND SHUTDOWN #2 ENG TO LOAD MORE BAGS. 2) THEN WE STARTED #2 ENG AGAIN; THEN THE #1 ENG. I WAS READING CHKLISTS AND THE CAPT RESPONDED APPROPRIATELY. 3) AT DEP TIME IT STARTED TO RAIN AND THE CAPT WAS ANXIOUS TO PULL AWAY FROM THE GATE. I RECEIVED THE TAXI CLRNC AND WE PROCEEDED OUT TO RWY 3; WE DID A TAXI CHK AND HELD SHORT OF RWY 3 (IT WAS A SHORT TAXI) AND I SPENT THE WHOLE TIME READING AND DOING CHKLIST. WE WERE WAITING FOR THE EFIS TIME COUNTDOWN TO FINISH. 4) AN ACR 737 WAS IN LINE AFTER US FOR TKOF. THE EFIS CHK FINISHED AND THE CTLR CLRED US FOR TKOF. WE REPEATED THE CLRNC RAN THROUGH THE BEFORE TKOF CHKLIST. THE CAPT NOTICED A ACW FAULT LIGHT ON THE #2 ENG OVERHEAD PANEL. HE APPLIED SOME PWR AND TOLD ME TO TELL TWR WE ARE TAXIING OFF (AT THE FIRST INTXN) WE TAXIED AROUND TO THE RWY 3 HERE AGAIN WHILE THE CAPT CYCLED THE FAULT LIGHTS AND SWITCHED OFF THE PROP BRAKE. 5) I THINK WE TAXIED FOR TKOF THE FIRST TIME WITH THE PROP BRAKE ENGAGED ON THE R ENG; I WASN'T AWARE OF IT AT THE TIME; BUT IT SEEMS TO BE THE CASE; IN OUR CHKLIST IT ONLY STATES THAT THE PROP BRAKE IS CHKED; IT SHOULD OF BEEN OFF BEFORE TAXI; I FIGURED THAT OUT WHEN THE CAPT REACHED FOR THE PROP BRAKE AFTER WE WERE OFF THE RWY. 6) THINGS HAPPENED QUICKLY AND THE CAPT WAS COMPLAINING OF LACK OF SLEEP. AND MISTAKES WERE MADE WITH THE CHKLISTS. THE EVENT WAS RPTED TO THE COMPANY AND THE FAA BY THE ACR 737 PLT. AN ONGOING INVESTIGATION IS IN PROGRESS.