Narrative:

On initial climb and less than 200 feet RA as PF I had noticed pressure on my ears that was similar to that of an excessive climb rate. I then observed the cabin climb rate was in excess of 1;000 feet per minute. At that time I also got a chime from the lead flight attendant informing me that the L-1 door had a gap and was not completely closed. The lead stated that the gap was big enough to slide his fingers through the gap. At the time of departure the aircraft weighed approximately 134;000 lbs. We contacted dispatch and notified them of our situation and intentions to burn fuel down to landing weight of 128;000 lbs and return for landing. We ran the weight balance for 128;000 lb landing and determined that we needed less than 5;000 feet of runway. Operations also concurred and supported our decision to reduce our landing weight and return to field. Declared emergency. Notified operations. Circled over the airport at 180 knots with the gear down flaps 15 at 4;000 feet MSL for 40 minutes. Returned to departure airport. Have gate agent verify that the door is completely sealed when door is shut. My understanding is that is common problem mechanically for the L-1 door.

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Original NASA ASRS Text

Title: B737-700 flight crew reports failure of the aircraft to pressurize after takeoff and is informed shortly by the Lead Flight Attendant that the forward entry door is not sealed properly with a gap along the bottom of the door. Crew elects to return to the departure airport after burning down to landing weight.

Narrative: On initial climb and less than 200 feet RA as PF I had noticed pressure on my ears that was similar to that of an excessive climb rate. I then observed the cabin climb rate was in excess of 1;000 feet per minute. At that time I also got a chime from the Lead Flight Attendant informing me that the L-1 door had a gap and was not completely closed. The Lead stated that the gap was big enough to slide his fingers through the gap. At the time of departure the aircraft weighed approximately 134;000 lbs. We contacted Dispatch and notified them of our situation and intentions to burn fuel down to landing weight of 128;000 lbs and return for landing. We ran the Weight Balance for 128;000 lb landing and determined that we needed less than 5;000 feet of runway. Operations also concurred and supported our decision to reduce our landing weight and return to field. Declared emergency. Notified Operations. Circled over the airport at 180 knots with the gear down flaps 15 at 4;000 feet MSL for 40 minutes. Returned to departure airport. Have gate agent verify that the door is completely sealed when door is shut. My understanding is that is common problem mechanically for the L-1 door.

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.