B757-200 pilot reported a 'left aft entry door' EICAS message on climb out through 9;000 feet. An em...

Narrative:

Normal takeoff; good plane no EICAS messages prior to departure. On climb out passing 9;000 feet; we got a 'left aft ent door' EICAS message along with the 'entry doors' annunciator illuminated. Flight attendants by the left aft entry door reported hearing a pop from the door; [observing] the door handle moving up a few inches; and seeing light along the bottom edge of the door. Cabin pressure was abnormal; showing a low differential and higher than average cabin pressure for around 10;000 feet. We felt the pressure surge and higher cabin climb rate in our ears as well. We leveled off the climb below 14;000 feet; declared an emergency; descended and returned uneventful landing. Aircraft was 1;500 lbs over max landing weight; overweight landing was soft. We stopped on high speed [taxiway] off runway; easy on brakes; and passengers remained seated. Arff met us; brakes were ok; and we taxied to gate. At gate; left aft door was left alone; as it would require the flight attendant to push down on handle to unarm the door; and maintenance met us immediately to inspect the door.we don't know why the door popped open during flight; but if there were item dropped along door edges; possibly causing the problem; maybe ground personnel servicing the doors need to be careful that things are not fouling the door.

Original NASA ASRS Text

Title: B757-200 pilot reported a 'L AFT ENTRY DOOR' EICAS message on climb out through 9;000 feet. An emergency was declared and the flight returned to departure airport.

Narrative: Normal takeoff; good plane no EICAS messages prior to departure. On climb out passing 9;000 feet; we got a 'L AFT ENT DOOR' EICAS message along with the 'ENTRY DOORS' annunciator illuminated. Flight attendants by the left aft entry door reported hearing a pop from the door; [observing] the door handle moving up a few inches; and seeing light along the bottom edge of the door. Cabin pressure was abnormal; showing a low differential and higher than average cabin pressure for around 10;000 feet. We felt the pressure surge and higher cabin climb rate in our ears as well. We leveled off the climb below 14;000 feet; declared an emergency; descended and returned uneventful landing. Aircraft was 1;500 lbs over max landing weight; overweight landing was soft. We stopped on high speed [taxiway] off runway; easy on brakes; and passengers remained seated. ARFF met us; brakes were ok; and we taxied to gate. At gate; left aft door was left alone; as it would require the Flight Attendant to push down on handle to unarm the door; and Maintenance met us immediately to inspect the door.We don't know why the door popped open during flight; but if there were item dropped along door edges; possibly causing the problem; maybe ground personnel servicing the doors need to be careful that things are not fouling the door.

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	1159997
Time
Date	201403
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.ARTCC
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Climb
Flight Plan	IFR
Component
Aircraft Component	Exterior Pax/Crew Door
Person 1
Function	Pilot Flying
Experience	Flight Crew Total 19000
Events
Anomaly	Aircraft Equipment Problem Less Severe

B757-200 pilot reported a 'left aft entry door' EICAS message on climb out through 9;000 feet. An emergency was declared and the flight returned to departure airport.