Understanding rapid decompression:
Rapid decompression occurs when a hole or breach in the aircraft’s fuselage leads to a swift loss of cabin pressure.Airplanes are pressurized to ensure a comfortable and safe environment for passengers and crew at high altitudes, where the outside air pressure is much lower than at sea level. If this pressurization is lost suddenly, it can create a dangerous situation.
Immediate effects of decompression:
The immediate effect of rapid decompression is the sudden drop in cabin pressure, leading to a host of potential problems:
- Oxygen deprivation: As cabin pressure drops, the amount of available oxygen decreases, potentially leading to
hypoxia for passengers and crew. - Temperature drop: The cabin temperature can plummet, as the air at cruising altitudes is extremely cold.
- Flying debris: Objects within the aircraft can become airborne due to the sudden change in pressure.
- Structural stress: The aircraft’s structure may be compromised, especially around the breach, which can exacerbate the situation.
Safety protocols and measures:
How to handle such emergencies
Modern aircraft, including the Boeing 737 MAX 9, are equipped with safety measures to handle such emergencies:
- Oxygen masks: Drop-down oxygen masks provide immediate access to oxygen, preventing hypoxia.
- Pilot training: Pilots are trained to respond quickly to decompression events, typically by initiating a rapid descent to lower altitudes where breathable air is available.
- Structural design: Aircraft are designed to withstand some degree of structural damage without catastrophic failure.
The Alaska Airlines incident:
This is what happened on January 5, 2024, when an Alaska Airlines flight with Boeing 737 MAX 9 suffered a blowout shortly after taking off from Portland, Oregon.
The blowout occurred when a panel that covers a spot left for an emergency door tore off from the left side of the jet, leaving a refrigerator-sized hole next to the passenger seats. The panel, or plug, is installed on some MAX 9s with fewer seats instead of an emergency exit door. The panel is supposed to be secured by four bolts that prevent it from sliding up on rollers when the plane is in flight. However, it is unclear whether the bolts were missing or broke off during the incident.
The sudden decompression caused oxygen masks to drop from the ceiling and the cabin temperature to drop. The pilot immediately signaled an emergency and turned back to Portland. The plane landed safely with all 171 passengers and six crew on board. Six people were injured, but none seriously.
Questions about Boeing aircraft
The incident raised questions about the safety and quality of Boeing’s 737 MAX 9 aircraft, which is a variant of the 737 MAX family that was grounded worldwide for 20 months after two fatal crashes in 2018 and 2019. The Federal Aviation Administration (FAA) ordered the grounding of 171 MAX 9s worldwide that have the same panel configuration as the Alaska Airlines plane until they are inspected and fixed.
Boeing CEO Dave Calhoun acknowledged the company’s mistake and vowed transparency in the investigation. He said the company would work with the FAA, the National Transportation Safety Board (NTSB), and the airlines to ensure the safety of the MAX 9 fleet. He also said the company would review its production processes and quality controls to prevent similar incidents in the future.
Calhoun said he had been “shaken to the bone” by the accident, which rekindled pressure on Boeing over its troubled small plane family almost five years after a full-blown MAX safety crisis sparked by deadly crashes in Indonesia and Ethiopia.
“We’re going to approach this, number one, acknowledging our mistake,” Calhoun told employees, according to an excerpt released by Boeing. “We’re going to approach it with 100% and complete transparency every step of the way.”
Alaska Airlines and United Airlines, the two US carriers that operate MAX 9s with the panel configuration, have grounded their entire fleets of 65 and 79 planes, respectively, for inspections and maintenance. This has resulted in hundreds of flight cancellations and disruptions for thousands of passengers. Other airlines that have grounded their MAX 9s include Copa Airlines, Aeromexico, and Turkish Airlines.
The NTSB has launched an investigation into the cause and circumstances of the blowout. It is also searching for the panel that blew off, which is believed to have landed near a highway in Oregon. The investigation is expected to last several months and could lead to recommendations for changes in the design, manufacturing, or maintenance of the MAX 9 aircraft.
The 737 MAX is Boeing’s best-selling plane and a key source of revenue and profit for the company. The company has delivered more than 600 MAX planes to airlines around the world and has more than 3,000 orders pending. The company has said it is confident in the safety and performance of the MAX family and has made significant improvements and enhancements to the planes since the grounding.
(With inputs from agencies)