Date: 201508
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Daylight
Aircraft: EMB ERJ 170/175 ER/LR
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Cruise
Airspace: Class A ZZZ
ATC / advisory: Center ZZZ
Aircraft component: Pressurization System
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Check Pilot
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Confusion; Troubleshooting; Time Pressure
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Detector: Person Flight Crew; Person Flight Attendant
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Landed As Precaution; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Overcame Equipment Problem; General Maintenance Action
Contributing factors: Incorrect / Not Installed / Unavailable Part; MEL; Aircraft
Primary problem: Aircraft

Narrative: It was a full flight with a jumpseater in the cockpit. We were delayed on departure by maintenance. The previous crew said the Flight attendants heard a thumping sound from the right rear service door. Maintenance removed the right rear service door deflector. That deflector was put on CDL and we pushed from the gate 26 minutes late. We departed without incident. As we were getting close to our cruising altitude of 35;000 feet the aft flight attendant called up and said the right rear service door was loud. We promptly checked the status page on the MFD and it showed locked and green. We also checked the EICAS screen and the Cabin Altitude and Differential Pressure were stable and at normal levels. As soon as we reached 35;000 feet we felt our ears pop. We both looked at the EICAS screen to see the cabin altitude increasing rapidly. Within seconds it went from normal to above 17;000 feet. We donned our oxygen masks immediately. The Cabin Alt Hi warning went off and we completed the [checklist]. We made an emergency descent to 10;000 feet. We completed the QRH items and when we reached 10;000 feet we told the passengers we were stabilized and level at 10;000 feet. We also said they can take their oxygen masks off and that we were diverting. We landed in ZZZ without incident.On the ground in ZZZ we called maintenance thru dispatch and logged the rapid decompression and Passengers Oxygen masks auto deployed in the [aircraft logbook]. During the postflight walkaround I noticed the right rear service door gasket had squeezed out thru the top of the door. As contract maintenance showed up at the plane he opened the right rear service door and noted that no bolts were in place to hold the door seal in place. Those are the same bolts that hold the door deflector plate to the outside of the service door. There was however clear packing tape present on the seal to apparently hold the seal in place until the door was closed.


Second narrative: Arriving to pre-flight the aircraft the First Officer found that maintenance was working on the right rear service door due to a write-up from the previous flight. The work was completed and released to the flight crew; resulting in a new CDL item for the removal of the Door deflector and a 26 minute delay. The flight pushed back from the gate and departed. During climb to FL350 the Flight Attendants called the cockpit complaining of extremely loud air noise coming from the right rear service door. The status page on the MFD showed all doors locked/green; the cabin altimeter; differential and rate were showing normal values appropriate for climb at altitude. As the aircraft was leveling at FL350 both the pilot flying; monitoring and cockpit jumpseater felt their ears pop; both pilot flying and monitoring checked the pressurization and noticed that the Cabin Altitude was rapidly rising to over 17;000 feet; O2 masks were donned immediately then the CAB ALT HI warning appeared on the EICAS; and the [checklist] was performed. The descent was initiated and diversion toward ZZZ completed. Throughout; the cockpit jumpseater assisted in co-ordination with the flight attendants; and radio communication with ATC while checklists were being performed. Upon reaching 10;000 feet the QRH items were completed and the captain made an announcement that it was safe to remove O2 masks. No further incidents occurred; a normal landing was executed; and emergency terminated. Once at the gate after shutdown was completed the captain made the appropriate entries in the [aircraft logbook]. Upon performing the post flight walk-around the first officer; captain and contract maintenance tech noted the door pressure seal on the right rear service door was protruding through the top of the door; upon opening the door; it was noted while speed tape was applied to the exterior of the door to cover the bolt holes of the removed door deflector; clear packing tape had been applied to the top corners of the inner door seal which was meant to be secured by the door deflector bolts that had been removed.


Synopsis: The captain of a regional jet reported a complete loss of pressurization at the top of climb necessitating an emergency descent and a diversion to an alternate airfield. The peak cabin pressure was reported as 17;000 feet. There were no injuries. A post flight inspection revealed an improper repair to an external service door.