Flight Crew reported the forward avionics compartment access door seal failed on take off; resulting in an air turn back and precautionary landing at departure airport.
Synopsis
Flight Crew reported the forward avionics compartment access door seal failed on take off; resulting in an air turn back and precautionary landing at departure airport.
Narrative
During departure climb through FL230 we experienced a loud bang/pop originating in the nose section of the aircraft immediately followed by a significant increase in volume of air rushing through the cockpit. Notified ATC; stopped the climb at FL280; checked that the aircraft was maintaining cabin altitude/pressurization; it was. Prior to push back we had to have the sensor on the avionics access door deferred per MEL. This coupled with the extremely loud sound of moving air in the cockpit; which was originating in the avionics bay (I opened the floor access door in the cockpit and verified there was no significant movement of air) we determined that the avionics door was still at least partially latched and that a possible door seal failure had occurred. Which was the case. A second pop was experienced with a momentary cabin rate of climb increase to 700 FPM. Contacted Dispatcher; decided to air turn back to ZZZ. Notified Maintenance. Vectored back to ILS [Runway] XX. No emergency declared or crash fire and rescue alerted. Uneventful descent and landing into ZZZ.Cause - Door seal failure; Avionics Access Door.
Second reporter narrative
[Report narrative contained no additional information]
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.