Narrative:

The airplane did not have an APU. We were on ground power and had external air hooked up. After boarding and loading all the bags; we were ready to close up. We had an air start that was running. I gave the signal (one hand flat; the other in an up-and-down motion; making a T) to the ground personnel to disconnect the air conditioning. He acknowledged with a nod. I gave him the signal for air disconnect again; waiting to see the signal as a response; rather than the nod. Second time he acknowledged me with a repeat of the hand motion. The first officer witnessed the exchange. We waited and then gave the signal for engine #2 start; to see if we were ready to switch to airplane power. He repeated it. I asked the flight attendant to close the main cabin door; in order to run the before start checklist. As the door closed; our ears started popping. We realized that the air was not disconnected. The door pages display showed that the 'srv' door was yellow. I could not see if it was open or improperly stowed. I sent the flight attendant to make sure it was closed. After that; the 'srv' door popped open. I quickly ran over to the open door. I saw the air conditioning hose was still inflated. I gave the ramper the signal to disconnect the air again. He walked up to the gpu and turned it off. We went dark with a plane full of people. I tried closing the 'srv' door and could not do it. We contacted the maintenance to find out the door had been damaged.

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Original NASA ASRS Text

Title: WITH THE APU INOPERATIVE AND DEFERRED; POOR HAND SIGNAL COMMUNICATION BETWEEN FLT AND GND CREWS RESULTS IN FIRST PRESSURIZING ACFT AT THE GATE AND THEN THE LOSS OF ALL ELECTRICAL POWER WHEN THE GPU IS COMPLETELY SHUT DOWN RATHER THAN SIMPLY SHUTTING OFF PNEUMATICS TO THE ACFT.

Narrative: THE AIRPLANE DID NOT HAVE AN APU. WE WERE ON GND PWR AND HAD EXTERNAL AIR HOOKED UP. AFTER BOARDING AND LOADING ALL THE BAGS; WE WERE READY TO CLOSE UP. WE HAD AN AIR START THAT WAS RUNNING. I GAVE THE SIGNAL (ONE HAND FLAT; THE OTHER IN AN UP-AND-DOWN MOTION; MAKING A T) TO THE GND PERSONNEL TO DISCONNECT THE AIR CONDITIONING. HE ACKNOWLEDGED WITH A NOD. I GAVE HIM THE SIGNAL FOR AIR DISCONNECT AGAIN; WAITING TO SEE THE SIGNAL AS A RESPONSE; RATHER THAN THE NOD. SECOND TIME HE ACKNOWLEDGED ME WITH A REPEAT OF THE HAND MOTION. THE FO WITNESSED THE EXCHANGE. WE WAITED AND THEN GAVE THE SIGNAL FOR ENG #2 START; TO SEE IF WE WERE READY TO SWITCH TO AIRPLANE PWR. HE REPEATED IT. I ASKED THE FLT ATTENDANT TO CLOSE THE MAIN CABIN DOOR; IN ORDER TO RUN THE BEFORE START CHKLIST. AS THE DOOR CLOSED; OUR EARS STARTED POPPING. WE REALIZED THAT THE AIR WAS NOT DISCONNECTED. THE DOOR PAGES DISPLAY SHOWED THAT THE 'SRV' DOOR WAS YELLOW. I COULD NOT SEE IF IT WAS OPEN OR IMPROPERLY STOWED. I SENT THE FLT ATTENDANT TO MAKE SURE IT WAS CLOSED. AFTER THAT; THE 'SRV' DOOR POPPED OPEN. I QUICKLY RAN OVER TO THE OPEN DOOR. I SAW THE AIR CONDITIONING HOSE WAS STILL INFLATED. I GAVE THE RAMPER THE SIGNAL TO DISCONNECT THE AIR AGAIN. HE WALKED UP TO THE GPU AND TURNED IT OFF. WE WENT DARK WITH A PLANE FULL OF PEOPLE. I TRIED CLOSING THE 'SRV' DOOR AND COULD NOT DO IT. WE CONTACTED THE MAINT TO FIND OUT THE DOOR HAD BEEN DAMAGED.

Data retrieved from NASA's ASRS site as of May 2009 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.