Expert said the cause of the crack is still unknown – Something may have hit the window, for example a bird, a large hailstorm, 'not unheard of'
An All Nippon Airways (ANA) domestic flight in Japan has returned to the airport after a crack in the cockpit window was reported.
According to the BBC, flight NH1182 had departed from the city of Sapporo in Hokkaido bound for Toyama on Japan's main island of Honshu when the incident occurred, in which no one was injured.
A spokesman for ANA, Japan's largest carrier, said the crack was spotted as the flight flew over Hakodate. "It was not something that affected the control or pressure of the flight," he said.
The plane headed back to the airport, from where it took off, where it made a safe landing.
The expert, John Strickland, said the cause of the crack was still unknown: "These things happen sometimes, something might have hit the window, for example a bird, a large hailstorm, it's not unheard of."
"Sometimes it can also happen due to pressure, wear and tear," he added, "but this is very rare."
He said the airline would likely have to replace the entire window, not just the broken section, to make sure the plane is completely safe.
The aircraft was carrying 59 passengers and six crew members. Alternative flights were arranged for the passengers.
The Alaska Airlines incident
This is the second incident involving a Boeing 737 aircraft within a few weeks. However, the ANA flight was not one of Boeing's 737 MAX 9 aircraft, but an older version that "wasn't old at all," Strickland said.
All Boeing 737-9s have been grounded by the US civil aviation regulator FAA, following an explosion on an Alaska Airlines jet in which a cabin panel fell from the new plane in mid-air, leaving a huge hole in the side of the fuselage last week.
The plane in question, carrying 177 passengers and crew, was forced to make an emergency landing in the US state of Oregon.
On Friday, the FAA indefinitely extended the grounding of Boeing 737 MAX 9 jets for further safety checks and said it would tighten its own oversight of Boeing.
Source: IN