Canadian air-safety regulator Transport Canada announced Thursday its approval of the Boeing 737 MAX design changes that were developed after two crashes killed 346 people in Indonesia and Ethiopia.
In a message Wednesday to the families of the Canadian victims of the Ethiopian crash, Nicholas Robinson, director general of Transport Canada, wrote that his agency “has now completed our independent review of the design changes and we have notified the FAA today that we have validated these changes with some unique Canadian differences.”
It’s one of the final steps in the process of clearing the plane to fly again in Canada, though that won’t be complete until Transport Canada issues a formal airworthiness directive and pilot-training requirements.
Robinson said that final clearance is expected in January.
Robinson’s message assured the families that “our process and review to validate these changes has been comprehensive; that our decisions have been independent and driven by the analysis of our globally recognized certification experts; and that we are confident in our validation outcome.”
Canadian MPs question the agency
The imminent Canadian clearance of the MAX comes despite recent criticism of Transport Canada’s oversight in the Canadian parliament.
Legislators highlighted a Transport Canada document, a copy of which was obtained by The Seattle Times, that revealed the agency’s test pilots had asked for clarification of the aircraft’s stall-handling system after a MAX certification flight back in 2016.
However, as revealed in a May 2017 memo, the agency deemed the issue not critical and agreed to a Boeing request to go ahead with certifying the MAX in June 2017 — though still without a response to its question — so that Boeing could meet its delivery schedule to Air Canada.
After the Lion Air crash in October 2018, Boeing told airlines for the first time of the existence of a new flight control system that went awry and caused the crashes — the Maneuvering Characteristics Augmentation System (MCAS).
A Transport Canada memo written a month later shows the agency felt it had been misled during the original certification in that how MCAS functioned was relevant to the question raised by the 2016 flight tests.
In a parliamentary committee hearing last month, David Turnbull, director of National Aircraft Certification at Transport Canada, told Canadian MPs that the agency was provided insufficient information about MCAS during certification in 2016 and 2017.
“Certain aspects of how the MCAS system functioned were not particularly made available by Boeing,” he said.
“In retrospect, we can look back at that and we can acknowledge that it was an aspect of the original certification that was not done properly,” he said. “We got the information that we got and we based our decision on the information that was available at the time.”
“We have learned an awful lot since then; there’s no question,” Turnbull added.
Turnbull has made the decision to revalidate the MAX.
“Obviously we have learned some lessons here — so has the FAA,” he said. “We’re going to be applying those lessons … for the future that may result in our taking a greater depth of review.”
Extra Canadian requirements
The “unique differences” Robinson mentioned refers to the fact that Canada will demand further MAX design enhancements of Boeing beyond those required by the U.S. Federal Aviation Administration (FAA).
One such difference mentioned by Turnbull in the parliamentary hearing is that Transport Canada will require that a MAX pilot be able to silence a “stick shaker” warning — a heavy and loud vibration of the control column that warns of a possible stall. The stick shaker was activated erroneously throughout both MAX flights that crashed, adding to confusion in the cockpits.
To avoid such severe distraction, Transport Canada wants Boeing — before the MAX’s return to service — to include flight manual instructions and training in how to pull circuit breakers to stop the stick shaker.
This will require Boeing to add collars or paint to the specific circuit breakers, which are in an overhead panel behind the pilots in the 737 cockpit, so the pilots can find them quickly in an emergency.
According to two people with knowledge of the matter, the FAA doesn’t favor pilots having to reach up and back to pull circuit breakers in an emergency.
In June, Annie Joannette, a spokesperson for Transport Canada, said Boeing is working on an alternative, long-term fix that could be implemented after the jet is back in service and that would allow deactivation “by means other than pulling the circuit breaker.”
Though Transport Canada has not specified what other extra requirements it will stipulate, Turnbull said it will have Boeing make “a number of future modifications.”
Agency spokesperson Cybelle Morin said via email that “these differences will include additional procedures on the flight deck and preflight, as well as differences in training.”