United Airlines Holdings Inc. has experienced three incidents involving its Boeing aircraft in the span of a week, with the latest incident occurring when a plane ran off the taxiway shortly after landing.

United Airlines Holdings Inc. has experienced three incidents involving its Boeing aircraft in the span of a week, with the latest incident occurring when a plane ran off the taxiway shortly after landing.

A United Airlines Holdings Inc. plane veered off the taxiway into a grassy area after landing at Houston, marking the third incident involving the carrier’s Boeing Co. planes this week.

United Flight 2477, carrying 160 passengers and six crew, had just landed at George Bush Intercontinental Airport around 8 a.m. local time when it went off course. There were no injuries, and passengers exited the 737 Max using mobile stairs before being bused to the terminal, according to the airline.

Friday’s incident involved a 737 Max aircraft built four years ago that has been in service for less than a year. It followed a tire coming off a United Boeing 777-200 on Thursday, shortly after takeoff from San Francisco on a flight to Osaka, Japan, and an engine issue on a United flight from Houston to Fort Myers, Florida, earlier in the week.

The flight from Houston to Florida had to make an emergency landing after an engine began emitting flames 10 minutes after takeoff. The engine had ingested plastic bubble wrap left on the airfield before departure, United said.

Boeing shares dropped as much as 1.4% after the United incident on Friday. The stock was down 0.8% as of 12:06 p.m. in New York, continuing to be the worst-performing stock this year among members of the Dow Jones Industrial Average. United slipped 0.5%.

The Boeing 777 heading to Osaka had 249 people on board. It diverted to Los Angeles International Airport and landed safely. The tire that fell off damaged at least one car in an airport parking lot.

The Federal Aviation Administration (FAA) said it would investigate all three incidents, while the National Transportation Safety Board (NTSB) is sending a team to Houston. United stated it would collaborate with the FAA, NTSB, and Boeing to understand the events. Despite occurring in quick succession, this week’s incidents do not seem related to known Boeing 737 Max issues and are unlikely to indicate broader safety trends.

Additionally, at least two other incidents involving United and Boeing occurred this week. On Monday, a United flight from Honolulu to San Francisco experienced an engine failure over the Pacific before landing safely. The FAA is also investigating a United flight from Pensacola, Florida, which safely landed in Chicago after reporting a gear issue with the 737 aircraft.

These incidents come at a challenging time for Boeing as it works to rebuild its reputation following a midair panel blowout on an Alaska Airlines flight earlier this year. The NTSB discovered that Boeing workers had apparently not attached four bolts holding the panel to the plane’s fuselage.

United Chief Executive Officer Scott Kirby has been among Boeing’s most vocal critics. United has removed the forthcoming 737 Max 10 from its planning and is exploring switching to other Max variants. The airline is also in discussions with Boeing competitor Airbus SE about alternative aircraft to replace some of its significant Max 10 order.

In a separate development related to the 737 Max, the FAA announced on Friday that the aircraft had wiring issues causing a flight-control panel to malfunction in flight, leading to jets rolling without pilot input. The agency ordered airlines to inspect wiring for chafing, as Boeing had alerted customers about the issue in July of last year.