Passengers onboard a Malaysia Airlines Boeing 737-800 reportedly got a scare when their plane suddenly dropped 7,000 feet on the weekend. The jet, en route from Kuala Lumpur to Tawau on Sunday, was turned around and returned to KL, with the airline later filing a Mandatory Occurrence Report with Malaysian aviation safety authorities.

Sudden drop causes passengers to "float" off their seats

According to a report in The New Straits Times, Malaysia Airlines flight MH2664 was 30 minutes into the flight when the incident occurred. A passenger onboard later said on social media the plane dived 7,000 feet in a matter of seconds, causing several passengers to "float" off the seats.

MH2664 is the 14:30 departure from Kuala Lumpur (KUL) to Tawau (TWU) in Sabah. On Sunday, the operating aircraft was 9M-MLS, an eight-year-old Boeing 737-800. Flight tracking website RadarBox.com shows the plane cruising over the South China Sea at about 30,000 feet when a sudden descent occurred. It shows a descent of about 17,000 feet, taking around 10 minutes. This ties up with the online comments from the passenger, who said the plane was "unstable" for about that 10 minutes. A second, smaller drop followed the first short, sharp drop.

Malaysia Airlines Flight MH2664

Malaysia Airlines attributes the incident to a "technical issue"

RadarBox.com shows the plane between Tioman Island and Pulau Jemaja when it turned around. The jet circled several times south of the capital before landing safely. Malaysia Airlines says the aircraft experienced technical issues during bad weather. The airline added the pilots decided to turn back to Kuala Lumpur as a precautionary measure.

"Flight MH2664 from Kuala Lumpur to Tawau on April 3 performed an air turn back because of technical issues with the aircraft, compounded by bad weather en route," says a statement from Malaysia Airlines. "The aircraft landed safely at KLIA at 5.03 pm. The safety of our crew and passengers remains of utmost importance to Malaysia Airlines."

The pilots won widespread praise online for their handling of a tricky incident and their decision to turn around. While the investigation remains ongoing, the Civil Aviation Authority of Malaysia says they'll be examining the plane's internal Flight Data Monitoring System, but indicate the pilots appear to have responded correctly.

Malaysia Airlines Boeing 737-800
The aircraft involved in Sunday's incident was a Boeing 737-800 (pictured). Photo: Boeing

Pocket of turbulence likely cause

One likely reason for the sudden drop is a pocket of turbulence, colloquially referred to as an 'air pocket'. In a nutshell, an air pocket is a region of low pressure causing an aircraft to lose height suddenly. Air pockets are just an extreme form of turbulence where a downdraft causes the aircraft to drop suddenly. Modern planes are built to withstand extreme turbulence, but an unexpected drop isn't much fun for people onboard, especially if not buckled in. Injuries (and more rarely, fatalities) are caused mainly by people and objects being tossed around the cabin. The passenger quoted in the New Straits Times report says people were screaming, crying, and fearing for their lives.

The operating aircraft, 9M-MLS, has had a relatively trouble-free run flying for Malaysia Airlines. In 2017, pilots operating a flight between Langkawi to Kuala Lumpur using the same plane initiated an emergency descent. The cabin did not pressurize properly, and the passenger oxygen masks had not deployed. Since Sunday's incident, the aircraft has remained on the ground in Kuala Lumpur.

Source: New Straits Times