Boeing’s 737 Max could be flying again before too long.
The plane has been grounded since last March, after two crashes in five months killed 346 people. The crisis has cost Boeing billions of dollars and led to the ouster of its chief executive, who repeatedly offered overly optimistic assessments of when the Max would be back in the air.
Now there are signs that the Max may return to service relatively soon. On Thursday, Stephen Dickson, the administrator of the Federal Aviation Administration, said a crucial test flight could occur in the coming weeks, setting in motion the complex process of ungrounding the plane.
He also revealed that there was yet another problem with the Max: an indicator light that erroneously activated because of an issue with the flight control computer. Boeing is working to resolve the issue, which the company said it did not believe would cause further delays.
Given the approaching test flight, and barring significant new problems, airlines like Southwest, American and United may be able to stick to their plans to use the Max this summer. Here’s what has to happen first.
Outstanding issues on the Max must be addressed.
The indicator light is just one of several issues that Boeing is still trying to resolve. Another major sticking point is whether Boeing needs to separate wire bundles that could, in rare circumstances, cause a short circuit and possibly lead to a catastrophic failure.
Boeing is evaluating the issue and publicly says it will turn its analysis over to the F.A.A. and allow the regulator to make a decision. Privately, the company is making the case that the bundles do not need to be separated, according to two people familiar with the matter. Some F.A.A. officials and European regulators, however, made it clear to Boeing that it must have a persuasive argument for not separating the wires.
“Regarding wire bundles, we continue to perform the appropriate analysis, including lab testing, fleet data assessment and third-party reviews,” Boeing said in a statement on Thursday. “It would be premature to speculate as to whether this analysis will lead to any design changes.”
Boeing is also still working with Collins Aerospace, one of its major subcontractors, to fix lingering issues with updates to the computers that control MCAS, the software that contributed to both crashes. Changes to the software have introduced new complications, such as the issue with the indicator light. Another irregularity, related to the software that monitors the plane as it powers up, is also being worked through.
When Boeing is convinced that all these issues are resolved, it will hand the updated software over to the F.A.A., which will issue what is known as a type inspection authorization memo. Once that is issued, the F.A.A. can conduct its certification flights.
The F.A.A. will fly the plane.
Pilots from the F.A.A. will take a 737 Max to the sky for a few flights over a couple of days in the Seattle area, where the plane is made. If the current timing holds, that could happen in late February or early March.
The test plane will be outfitted with sensors and other monitoring equipment, and F.A.A. officials will be joined by a top Boeing test pilot.
If all goes well, the F.A.A. will conclude that the Max flew as expected. But if it finds other issues, it could require additional work from Boeing.
After the successful completion of the certification flights, Boeing will compile a final package of certification documents to submit to the F.A.A., which could take another couple of weeks.
Training for pilots must be decided.
After the certification flights, international regulators will convene for several days to determine final training requirements for the Max. Last month, Boeing said it would recommend that pilots train in flight simulators before flying the Max. Regulators are likely to concur, though the specifics have yet to be determined.
The regulators will then offer training to more than a dozen flight crews from airlines around the globe and test their responses to emergencies on the Max in a flight simulator.
After those tests, the F.A.A. will produce a report recommending training, which will be open to public comments for 15 days. After the public comment period, the agency will release its final training requirements.
The grounding would formally end.
Once the certification flights are done, the paperwork is complete and the training is set, the F.A.A. will issue an airworthiness directive instructing airlines how to install new software and fix other issues on the Max so that it can fly again. It will then release a separate document formally ending the grounding.
Boeing will also send a bulletin, containing much of the same information, to the airlines that operate the 737 Max. With those steps complete, pilots could begin training.
The F.A.A. is not the only aviation regulator that needs to clear the Max. Officials in Europe, Canada, Brazil and other countries will have to make their own decisions. And while there is a good chance that some international regulators may give the Max the all-clear at the same time as the F.A.A., some could take longer.
Get the planes ready to fly.
When airlines are finally prepared to fly the Max, they will have to get their planes ready. That process — which involves checking all the plane’s systems, as well as its fluids, engines, tires and more — takes a week to 10 days per plane. Airlines are also likely to give the interiors a deep cleaning, and they will have to install the updated software, which should take only a few hours.
Boeing will go through a similar process for the roughly 400 jets built during the grounding that are now in storage. The backlog of completed jets contributed to Boeing’s decision to temporarily shut the 737 factory last month. It will take well over a year to deliver all the already built planes to customers, and Boeing wanted to stop the backlog from growing.
Moving the first planes out of storage and into the hands of customers will be a major milestone for Boeing, and it will signal that the return of the Max is imminent.
Convince passengers the plane is safe.
Once the Max is approved, airlines face the task of persuading people to get on it. Boeing’s own research shows that as of December, 40 percent of travelers said they were unwilling to board a Max. And while Boeing has briefed airlines on its plans to help convince the flying public that the Max is safe to fly, many airline executives acknowledge that it could be a difficult sell, especially early on.