Narrative:

We arrived on the ramp and two company aircraft were being pushed out. There was sufficient space for us to safely enter the gate. The marshaller signaled us to proceed. The safety zone was clear and we followed the marshaller's instructions to a stop and set the parking brake. The #1 engine was still running while we waited for ground power to be connected. As the jet bridge contacted the aircraft; the plane began to shake and loud banging noises could be heard. At this point; I believed there had been a malfunction in the jetbridge and it was repeatedly banging against the aircraft. I then saw four ramp personnel run from the area of the jetbridge out in front of the aircraft and gather in front of the nose on the starboard side. Shortly after that; another member of the ground crew moved into view on the captain's side of the nose and made 'kill it' throat slashing gestures. We immediately shut down the #1 engine. The captain had started the APU; but the start cycle was incomplete. The captain made an announcement to the passengers to stay seated. We put the APU generator online when it became available. The captain went outside. When he returned; I learned that the #1 engine had ingested the conditioned air hose. I am unfamiliar with and therefore unqualified to speculate on ramp personnel procedures. After the event; one of the ramp personnel informed me that the chains that secure the conditioned air hose to the jetbridge were not attached and movement of the jetbridge had caused the conditioned air hose to accordion out into the ingestion area. But I must stress that I did not witness this.

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Original NASA ASRS Text

Title: A B737-700's left engine ingested an unsecured jetway conditioned air hose chain after parking at its gate under a Marshaller's guidance.

Narrative: We arrived on the ramp and two Company aircraft were being pushed out. There was sufficient space for us to safely enter the gate. The Marshaller signaled us to proceed. The safety zone was clear and we followed the Marshaller's instructions to a stop and set the parking brake. The #1 engine was still running while we waited for ground power to be connected. As the jet bridge contacted the aircraft; the plane began to shake and loud banging noises could be heard. At this point; I believed there had been a malfunction in the jetbridge and it was repeatedly banging against the aircraft. I then saw four ramp personnel run from the area of the jetbridge out in front of the aircraft and gather in front of the nose on the starboard side. Shortly after that; another member of the ground crew moved into view on the Captain's side of the nose and made 'kill it' throat slashing gestures. We immediately shut down the #1 engine. The Captain had started the APU; but the start cycle was incomplete. The Captain made an announcement to the passengers to stay seated. We put the APU generator online when it became available. The Captain went outside. When he returned; I learned that the #1 engine had ingested the conditioned air hose. I am unfamiliar with and therefore unqualified to speculate on ramp personnel procedures. After the event; one of the ramp personnel informed me that the chains that secure the conditioned air hose to the jetbridge were not attached and movement of the jetbridge had caused the conditioned air hose to accordion out into the ingestion area. But I must stress that I did not witness this.

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.