U.S. airliners late Wednesday joined the growing list of airline companies around the world grounding their fleets of Boeing 737 Max 8 jet aircraft following Sunday’s crash of an Ethiopian Airlines jet that killed all 157 people aboard. The move on the part of U.S. carriers came after Canadian aviation authorities grounded planes earlier in the day. The FAA went on record Tuesday saying:

“The FAA continues to review extensively all available data and aggregate safety performance from operators and pilots of the Boeing 737 MAX. Thus far, our review shows no systemic performance issues and provides no basis to order grounding the aircraft. Nor have other civil aviation authorities provided data to us that would warrant action. In the course of our urgent review of data on the Ethiopian Airlines Flight 302 crash, if any issues affecting the continued airworthiness of the aircraft are identified, the FAA will take immediate and appropriate action.”

By Wednesday afternoon that statement changed to:

“The FAA is ordering the temporary grounding of Boeing 737 MAX aircraft operated by U.S. airlines or in U.S. territory. The agency made this decision as a result of the data gathering process and new evidence collected at the site and analyzed today. This evidence, together with newly refined satellite data available to FAA this morning, led to this decision. The grounding will remain in effect pending further investigation, including examination of information from the aircraft’s flight data recorders and cockpit voice recorders. An FAA team is in Ethiopia assisting the NTSB as parties to the investigation of the Flight 302 accident. The agency will continue to investigate."

Southwest Airlines removed all 34 of its 737 Max 8 aircraft from service Wednesday after the announcement. However, flight schedules are not expected to be disrupted as the grounded aircraft account for less than 5 percent of Southwest’s daily operating fleet.

The airline is allowing customers booked on canceled flights to rebook on an alternate flight at no added fee or fare increase if the new flight upholds the same route is scheduled to depart within 14 days of the canceled trip.

United Airlines announced its intention to ground all of its 737 Max 9 aircraft, which account for 40 flights per day.

American Airlines complied with the order, grounding its fleet of 24 717 Max 8 aircraft.

So far, some 45 airline companies have decided to ground their fleets of operating Boeing 737 Max 8 or 9 aircraft, other carriers are still working on their response to this growing concern or had already grounded those models prior to the Sunday’s airline disaster.