The person in charge of relevant departments of the Civil Aviation Administration released the investigation results of the cabin pressure relief event of Shenzhen Airlines and the mechanical failure return event of China Eastern Airlines on August 9 on August 13. After investigation, this incident was caused by the failure of the rear cargo door sealing strip of the aircraft. Cabin pressure relief events are usually caused by cabin and cargo compartment sealing problems or air conditioning pressurization system failures.

In view of this failure event, the technical director of Dongsheng seal analyzed that the failure of cargo tank seal is mostly related to the sealing strip used. One is the material we choose when using the sealing strip. The material of aircraft cargo tank sealing strip shall meet the wear resistance, high pressure resistance, dielectric performance, etc. if one of them fails to meet the requirements, it will cause the failure. The second is the service life. If the sealing strip is not replaced in time due to long-term use, it will also cause certain wear and tear, resulting in leakage.

Therefore, the rubber sealing strip shall be selected as the base material for the sealing strip for aircraft cargo hold or cabin doors and windows, and the fabric with appropriate elongation at break and friction shall be used as the skeleton sealing material. Since the structure and opening and closing form of aircraft cargo hold door can not be changed, in order to achieve good sealing effect, L-shaped sealing strip and toothed sealing element are good choices. The sealing effect is achieved through the compression deformation of the edge of the L-shaped sealing strip and the multi-channel sealing fit of the toothed seal. When the cargo hold emergency door frame is closed, the L-shaped sealing strip can be installed into the emergency door frame with the cargo hold emergency door body and produce rotational compression deformation. The toothed sealing belt fixed on the frame can produce vertical compression deformation. The combined deformation of the two kinds of sealing strips can block the edge of the frame, which can ensure the sealing of water and gas after the door body is closed.