Narrative:

As we approached the gate I started up the APU, and I called the safety zone clear. The captain then shut down the left engine and we taxied into the gate. I called the APU on line and the captain set the brakes. I did my flow to turn the pack switches to high pressure bleed off, turned on the APU air, since warm air condition was required, and opened the pneumatic xfeed valve. Then I noticed that the packs were oscillating back and forth and did not stabilize. I then turned the left pack off, waited a second to see if it would stabilize and it did. I believe I started the post engine shutdown flow and I believe the captain called for the parking check. After a run through the parking check, as it was the last leg of the trip (but not the aircraft), the captain asked for the in times while he did the logbook and I did the acar's. The captain got up and went in the back to say good-bye to the flight attendants and left. I stayed and said good-bye to most of the remaining people until a wheelchair arrived for a passenger -- I felt in the way so I said good-bye to the lead flight attendant and I left. Upon arriving home 5 hours later there was a message to call the chief pilot. To my surprise he informed me that we had left the remaining engine running at the gate. I could not believe this. Looking back on the day, with over 13 hours of duty (8.3 hours block) and 5 legs in winter IFR, and no time to eat a normal meal, I was tired at the completion of this trip.

Google
 

Original NASA ASRS Text

Title: ACR FLC FAILS TO SHUT DOWN ENG AT GATE PRIOR TO LEAVING ACFT.

Narrative: AS WE APCHED THE GATE I STARTED UP THE APU, AND I CALLED THE SAFETY ZONE CLR. THE CAPT THEN SHUT DOWN THE L ENG AND WE TAXIED INTO THE GATE. I CALLED THE APU ON LINE AND THE CAPT SET THE BRAKES. I DID MY FLOW TO TURN THE PACK SWITCHES TO HIGH PRESSURE BLEED OFF, TURNED ON THE APU AIR, SINCE WARM AIR CONDITION WAS REQUIRED, AND OPENED THE PNEUMATIC XFEED VALVE. THEN I NOTICED THAT THE PACKS WERE OSCILLATING BACK AND FORTH AND DID NOT STABILIZE. I THEN TURNED THE L PACK OFF, WAITED A SECOND TO SEE IF IT WOULD STABILIZE AND IT DID. I BELIEVE I STARTED THE POST ENG SHUTDOWN FLOW AND I BELIEVE THE CAPT CALLED FOR THE PARKING CHK. AFTER A RUN THROUGH THE PARKING CHK, AS IT WAS THE LAST LEG OF THE TRIP (BUT NOT THE ACFT), THE CAPT ASKED FOR THE IN TIMES WHILE HE DID THE LOGBOOK AND I DID THE ACAR'S. THE CAPT GOT UP AND WENT IN THE BACK TO SAY GOOD-BYE TO THE FLT ATTENDANTS AND LEFT. I STAYED AND SAID GOOD-BYE TO MOST OF THE REMAINING PEOPLE UNTIL A WHEELCHAIR ARRIVED FOR A PAX -- I FELT IN THE WAY SO I SAID GOOD-BYE TO THE LEAD FLT ATTENDANT AND I LEFT. UPON ARRIVING HOME 5 HRS LATER THERE WAS A MESSAGE TO CALL THE CHIEF PLT. TO MY SURPRISE HE INFORMED ME THAT WE HAD LEFT THE REMAINING ENG RUNNING AT THE GATE. I COULD NOT BELIEVE THIS. LOOKING BACK ON THE DAY, WITH OVER 13 HRS OF DUTY (8.3 HRS BLOCK) AND 5 LEGS IN WINTER IFR, AND NO TIME TO EAT A NORMAL MEAL, I WAS TIRED AT THE COMPLETION OF THIS TRIP.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.