Narrative:

I noticed a strong metallic smell and at the same time I could hear the bell going off for the interphone. I picked up the interphone and I think it was flight attendant B saying that there were fumes in the cabin and it was hard to breathe. I immediately went into the cockpit and told the captain that they were calling and saying fumes were in the cabin and they were having difficulty breathing. I heard one of the flight crew members say they could smell it. I told the captain I was going to stand on the jetway. The smell was overwhelming at some point and it changed to a rotten egg smell. I could hear passengers coughing. The captain came out of cockpit and said to stop boarding. I went up to the top of jetway to inform agents and they said that boarding was over but there were about 25 people standing in the jetway waiting to board. I told passengers in jetway we had to stop boarding and to please wait and then the a flight attendant came out of the jetway next to the door because the fumes were so strong. The captain finally came up to us and told us and the agent to deplane the passengers. I made an announcement telling passengers they needed to deplane and take their carry on luggage with them due to a mechanical issue. I stood at the door on jetway during deplaning. Passengers were complaining about the smell and then an elderly woman was trying to deplane but was gasping for air. I wasn't sure if she was having a heart attack or what and then the son said she was having [an] asthma attack from the fumes. She was yelling and gasping and he was digging in her roller board for her inhaler. The agent was standing next to her and he was telling her to suck on the inhaler and calm down. She inhaled 3 or 4 times and they put her in a wheelchair. The flight attendant on our jumpseat said that she saw her in the boarding area on oxygen. We continued deplaning and during the deplaning process I started getting a very bad headache. Then all flight attendant's came off the plane. Flight attendant a had a headache and flight attendant B also had a headache and looked awful. We waited in boarding area for over 2 hours and the flight was finally canceled and we went to the hotel. The lead mechanic told us that it was oil leak in the APU that leaked onto the packs.

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Original NASA ASRS Text

Title: An A321 APU developed an oil leak during boarding which contaminated the cabin air affecting the passengers and crew so the passengers were deplaned; the flight canceled and the aircraft removed from service.

Narrative: I noticed a strong metallic smell and at the same time I could hear the bell going off for the interphone. I picked up the interphone and I think it was Flight Attendant B saying that there were fumes in the cabin and it was hard to breathe. I immediately went into the cockpit and told the Captain that they were calling and saying fumes were in the cabin and they were having difficulty breathing. I heard one of the flight crew members say they could smell it. I told the Captain I was going to stand on the Jetway. The smell was overwhelming at some point and it changed to a rotten egg smell. I could hear passengers coughing. The Captain came out of cockpit and said to stop boarding. I went up to the top of Jetway to inform agents and they said that boarding was over but there were about 25 people standing in the Jetway waiting to board. I told passengers in Jetway we had to stop boarding and to please wait and then the A Flight Attendant came out of the Jetway next to the door because the fumes were so strong. The Captain finally came up to us and told us and the agent to deplane the passengers. I made an announcement telling passengers they needed to deplane and take their carry on luggage with them due to a mechanical issue. I stood at the door on Jetway during deplaning. Passengers were complaining about the smell and then an elderly woman was trying to deplane but was gasping for air. I wasn't sure if she was having a heart attack or what and then the son said she was having [an] asthma attack from the fumes. She was yelling and gasping and he was digging in her roller board for her inhaler. The agent was standing next to her and he was telling her to suck on the inhaler and calm down. She inhaled 3 or 4 times and they put her in a wheelchair. The Flight Attendant on our jumpseat said that she saw her in the boarding area on oxygen. We continued deplaning and during the deplaning process I started getting a very bad headache. Then all flight attendant's came off the plane. Flight Attendant A had a headache and Flight Attendant B also had a headache and looked awful. We waited in boarding area for over 2 hours and the flight was finally canceled and we went to the hotel. The Lead Mechanic told us that it was oil leak in the APU that leaked onto the packs.

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.