B737 captain reported that while deplaning the aircraft at the gate; there was an abrupt aircraft mo...

Narrative:

While parked at ord the passengers were disembarking and I was seated in my seat when suddenly the control wheel violently slammed back into me and simultaneous the aircraft started to slide sideways. I immediately placed the electrical hydraulic systems on and within a second the control wheel moved forward; I was able to apply brake pressure to stop the sideways movement of the aircraft. I called ramp control and asked who was behind me. He stated it was a B777. I informed him what happened. I then got up after everything appeared to be stable and went to the main cabin door to make sure everybody was ok. To my surprise; the aircraft moved about 2 feet. There was a 2-foot gap between the jet bridge and the aircraft. We were lucky no passengers fell through as they were getting off. I then went downstairs to make sure there were no injuries on the ground. I talked to the lead ramp person and he said all okay; by then maintenance was there and inspected the aircraft. He stated all was fine.

Original NASA ASRS Text

Title: B737 Captain reported that while deplaning the aircraft at the gate; there was an abrupt aircraft movement. This movement was attributed to a heavy Boeing 777 taxiing behind his aircraft. No injuries were reported.

Narrative: While parked at ORD the passengers were disembarking and I was seated in my seat when suddenly the control wheel violently slammed back into me and simultaneous the aircraft started to slide sideways. I immediately placed the electrical hydraulic systems on and within a second the control wheel moved forward; I was able to apply brake pressure to stop the sideways movement of the aircraft. I called ramp control and asked who was behind me. He stated it was a B777. I informed him what happened. I then got up after everything appeared to be stable and went to the main cabin door to make sure everybody was ok. To my surprise; the aircraft moved about 2 feet. There was a 2-foot gap between the jet bridge and the aircraft. We were lucky no passengers fell through as they were getting off. I then went downstairs to make sure there were no injuries on the ground. I talked to the lead ramp person and he said all okay; by then maintenance was there and inspected the aircraft. He stated all was fine.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1507315
Time
Date	201712
Local Time Of Day	1201-1800
Place
Locale Reference	ORD.Airport
State Reference	IL
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Type 8507
Events
Anomaly	Deviation - Procedural Published Material / Policy Ground Event / Encounter Other / Unknown

B737 captain reported that while deplaning the aircraft at the gate; there was an abrupt aircraft movement. This movement was attributed to a heavy boeing 777 taxiing behind his aircraft. No injuries were reported.