FAA is investigating how Boeing, Airbus jets may have ended up with counterfeit titanium. Here's a timeline of the company's mounting problems.

Plus, the FAA is also probing a "Dutch roll" incident.

The Federal Aviation Administration has opened two more investigations into Boeing. The first probe was prompted by an incident in which a 737 Max experienced a rare event known as a "Dutch roll," and the second, which also involves Airbus planes, follows a report that counterfeit titanium may have been used in some jet parts.

Boeing has faced heightened scrutiny since the start of 2024, with Congress calling on top executives to testify at a Senate hearing in mid-April over whether the company’s corporate culture prioritized money-saving measures over safety in its production of the 787 Dreamliner and the 777 aircraft.

In May, a Southwest flight from Phoenix to Oakland, Calif., experienced a Dutch roll at 32,000 feet midflight. A Dutch roll is when a plane’s tail slides and the aircraft starts rocking from side to side simultaneously, which impacts the plane’s stability, potentially throwing the aircraft off course or making it too difficult to turn. It is a rare situation, but pilots are trained on how to recover from it.

The May 25 flight did not result in any injuries to the passengers or crew.

An early report by the FAA found that there was damage to a unit that provides the backup power to the rudder, which controls the plane’s rotation and stability.

Separately, the New York Times reported on June 14 that a recent investigation by supplier Spirit AeroSystems found that counterfeit titanium, sold with falsified documents, was used to build parts for Boeing and Airbus jets. It is unclear how many planes may have parts made of counterfeit titanium and how it may affect the structural integrity of those aircraft.

Boeing has responded that most of its plane materials have been tested and remain unaffected. The aircraft that allegedly have components made with the material were built between 2019 and 2023 and include some Boeing 737 Max and 787 Dreamliner planes.

  • The Seattle Times reports a second Boeing whistleblower died after spending two weeks in the hospital from a sudden infection. Joshua Dean accused Boeing supplier Spirit AeroSystems of ignoring manufacturing defects on the Boeing 737 Max model before being fired in 2023.

  • FAA announces investigation into near-miss incident at LaGuardia Airport involving Southwest Airlines 737 on March 23.

  • Southwest Airlines Boeing 737 makes an emergency landing at Preston Smith International Airport after a small fire in the left engine.

  • Boeing pays Alaska Airlines $160 million to make up for losses the airline suffered following the mid-flight door plug blowout.

  • FAA announces investigation into claims made by new Boeing whistleblower, Sam Salehpour, an engineer who had worked on the 787 and 777 aircraft. He alleged that the planes were improperly fastened together and he was worried that after years of use, the planes could break apart mid-flight.

  • United Airlines claims the emergency grounding of the Boeing 737 Max 9 jetliner cost the company $200 million in the first three months of the year.

  • In a Senate hearing, lawmakers called multiple aviation safety specialists and former Boeing employees to testify. Witness Sam Salehpour, a quality engineer at Boeing, alleged that the company had ignored all of the issues he’d flagged with the 787 aircraft and that he was “subjected to threats of violence from my supervisor” after he spoke out.

Read more from the Associated Press: Boeing put under Senate scrutiny during back-to-back hearings on aircraft maker's safety culture

  • The FBI is investigating the Alaska Airlines flight in January in which a door plug blew off the plane midflight — and has told passengers they may be “a possible victim of a crime.”

  • The FAA’s 737 Max production audit finds multiple instances in which Boeing allegedly did not comply with manufacturing quality control requirements.

  • In two separate incidents, a Boeing 777-200 loses a wheel during takeoff from San Francisco and a Boeing 737 skids off the runway after landing in Houston.

  • The next week, a prominent Boeing whistleblower — former employee John Barnett — dies by suicide while in Charleston, S.C., for a deposition for a lawsuit against Boeing.

  • A Boeing 787 Dreamliner nosedives during a flight from Sydney to Auckland, New Zealand, injuring at least 50 people, on the same day a Boeing 777 flight from Sydney is forced to turn around due to a maintenance issue.

  • Another Boeing 777 is forced to make an emergency landing at Los Angeles International Airport after pilots report a flat tire.

  • A Boeing 737 that took off from San Francisco later that week is found to be missing a panel during a postflight inspection.

  • Boeing sues Virgin Galactic, accusing it of stealing trade secrets.

  • Boeing CEO Dave Calhoun announces he will be stepping down by the end of the year. The CEO of Boeing Commercial Airplanes, Stan Deal, is retiring and Boeing’s chairman, Larry Kellner, will not be seeking reelection as a board director.

  • A United Airlines Boeing 777 flight from San Francisco to Paris was diverted to Denver due to an engine issue.

  • A United Airlines Boeing 787 plane headed to Newark, N.J., from Tel Aviv, Israel, was forced to make an emergency landing at New York Stewart International Airport because of extreme turbulence. Seven passengers were taken to the hospital and 15 were treated on-site for injuries.

  • An Alaska Airlines Boeing 737 Max 9 jet from Honolulu to Anchorage, Alaska, was forced to turn back after a malfunctioning bathroom sink flooded the cabin.

Whistleblowers, nosedives and a DOJ investigation: Read more about Boeing’s March mishaps on Yahoo News

  • The NTSB publishes a preliminary report that found the Alaska Airlines flight was missing four key bolts, which is why the door plug blew out.

  • Alaska Airlines Flight 1282 experiences a door plug blowout midflight. The FAA subsequently grounds all Max 9 aircraft to investigate.

Read more from BBC News: Passenger describes being on Alaska Airlines Flight 1282

  • Boeing urges airlines to inspect all 737 Max jets for potential loose hardware in the plane’s rudder control systems.

  • Boeing reports a supplier quality issue with 737 Max planes involving improperly drilled holes.

  • The FAA tells Boeing that some documents submitted for the certification review of the 737 Max 7 are incomplete.

  • China’s aviation regulator claims there are major safety concerns with the Boeing Max jets.

  • The FAA allows Boeing 737 Max planes to fly again.

  • An 18-month-long investigation by a House of Representatives panel concludes that Boeing failed in its design and development of the Max aircraft and was not fully transparent with the FAA.

Read more from Reuters: U.S. lawmakers fault FAA, Boeing for deadly 737 Max crashes

  • Boeing suspends all 737 production.

“We’ve known [about Boeing] for five years,” Mark Pegram, father of one of the Ethiopian Airlines flight victims, told NPR in March. “I think the rest of the world is finally waking up to it, that these weren’t just isolated incidents.”

Boeing has paid billions of dollars in settlements since 2018, and the company and its leaders entered into a deferred prosecution agreement in January 2021 with the Department of Justice that has so far helped them avoid criminal prosecution.

Boeing paid $1.77 billion to compensate airline customers, $243.6 million as a criminal fine and $500 million for a compensation fund for family members of crash victims, CNN reported.

A yearlong FAA-commissioned panel review was critical of the safety culture at Boeing, and found that executives and employees were not aligned with what the safety standards were, according to a report released in February. The investigation also found that many employees were afraid of retaliation for speaking up.