Narrative:

As I advanced the thrust levers I heard a loud bang. I saw that the flight deck door had come open and the captain was trying to close it. Because of the abnormal situation I thought it was a good idea to abort. I started to pull the thrust levers back but the captain said to continue the takeoff because he was closing the door so I immediately put them back into the detent. We then got an aural 'takeoff spiolers' warning and the captain called for an abort.we exited the runway; advised ATC; addressed the passengers then discussed the cause of the warning. We decided that my reduction of the thrust levers caused the spoilers to extend; then returning them to the detent set off the takeoff warning logic. When the captain told me to continue the takeoff he didn't know that I had already starting reducing them. We also discussed the door opening. The captain had locked and hit the door prior to push. We ran checklists; checked the door and taxied back for another takeoff.the threat for me was the distraction caused by the captain sliding back and turning around and not exactly sure who was in control of the trust levers. The error was me deciding that aborting was the right thing to do; pulling the thrust levers back; then returning them to the detent when the captain said to continue. I have learned: to check the door better; push harder and check it myself. Never continue the takeoff after reducing the thrust levers. Don't assume the captain knows what I'm doing with the airplane without better communication.

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Original NASA ASRS Text

Title: The distraction of the cockpit door opening at the start of the takeoff roll contributed to miscommunication between an EMB-145 flight crew regarding whether or not to continue the takeoff. The pilot flying's momentary reduction of thrust triggered the spoilers and made the decision for them. After securing the door and debriefing the event; a subsequent takeoff was made without incident.

Narrative: As I advanced the thrust levers I heard a loud bang. I saw that the flight deck door had come open and the Captain was trying to close it. Because of the abnormal situation I thought it was a good idea to abort. I started to pull the thrust levers back but the Captain said to continue the takeoff because he was closing the door so I immediately put them back into the detent. We then got an aural 'TAKEOFF SPIOLERS' warning and the Captain called for an abort.We exited the runway; advised ATC; addressed the passengers then discussed the cause of the warning. We decided that my reduction of the thrust levers caused the spoilers to extend; then returning them to the detent set off the takeoff warning logic. When the Captain told me to continue the takeoff he didn't know that I had already starting reducing them. We also discussed the door opening. The Captain had locked and hit the door prior to push. We ran checklists; checked the door and taxied back for another takeoff.The threat for me was the distraction caused by the Captain sliding back and turning around and not exactly sure who was in control of the trust levers. The error was me deciding that aborting was the right thing to do; pulling the thrust levers back; then returning them to the detent when the Captain said to continue. I have learned: To check the door better; push harder and check it myself. NEVER continue the takeoff after reducing the thrust levers. Don't assume the Captain knows what I'm doing with the airplane without better communication.

Data retrieved from NASA's ASRS site as of July 2013 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.