It is the longest global grounding of an airliner in the history of civil aviation. The grounding was first put in place on March 13, 2019. But now it is due to be lifted. As expected the US aviation authority FAA published a so-called airworthiness directive advisory on November 18, detailing the requirements for the return of the Boeing 737 MAX to scheduled passenger service.

American Airlines is already offering flights with the Boeing aircraft starting on December 29 between New York and Miami in its computer reservation systems.

The jet's problems started with two crashes and a total of 346 victims. After that Boeing's bestseller 737 MAX was banned from global skies. It was found that malfunctions and deficiencies in the new automatic MCAS flight trimming system were major factors in both catastrophes, along with a lack of specific pilot training in how to handle it, due to cost concerns.

In addition, the 737 MAX crisis exposed a blatant lack of FAA oversight of Boeing. It came to light that the regulator had been delegating many of its oversight tasks to the company itself. These insights severely damaged both the reputation and business prospects of Boeing, traditionally the world's largest supplier of passenger aircraft.

It also threw into doubt a finely tuned system of certification for new aircraft followed globally for decades, most notably the key role the FAA played in the process. The US aviation regulator's verdicts were adopted by other certification authorities around the world almost automatically without any questions.

Getting back in the air

The European Aviation Safety Agency (EASA) headquartered in Cologne has announced that it will follow suit in due time once the FAA has recertified the 737 MAX for service. The European authority has already indicated it was satisfied with the modifications made to the aircraft since its grounding, including to the software of the MCAS system. This means even European airlines would soon be able to fly their MAX jets.

Still, on top of the modifications already agreed upon, EASA insists on developing an additional synthetic sensor to allow onboard systems to confirm the aircraft's angle of attack in flight. This extra development can take up to two years and is supposed to happen when the 737 MAX is already flying again.

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Getting the 737 MAX back in the air, despite dismal global passenger numbers due to the coronavirus, is also in the best interest of at least one big European customer.

"The MAX is key to our strategy going forward," said Ryanair CEO Eddie Wilson recently during an online conference. "The earlier they come the better. We are ready, when we get the MAX coming we can lower our costs even more." 

The Irish low-cost carrier is the biggest European customer of the 737 MAX with 135 orders, though it is not one of the airlines that already operated any of the 385 aircraft delivered before the grounding. "We assume we will take delivery of our first MAXs in summer maybe," said Wilson.

Orders canceled across the books

There is no urgency, however, among European customers to pick up any of the 470 aircraft currently stored in Seattle and its surroundings. Besides Ryanair, these include Norwegian Air Shuttle with 110 orders, Turkish Airlines (75) and TUI Group (72). 

"Due to the virus, there is no rush for anyone besides Boeing," said Sean Broderick, an aviation safety expert for US industry portal Aviation Week. It is especially important to Boeing since they only get paid at handover; before that the stored aircraft only costs the manufacturer money.

In the meantime, many customers have canceled orders. Out of original almost 4,400 commitments, a total of 1,043 have now been removed from the books after cancellations or switches to other models. In October alone, the MAX order volume shrunk by 448 aircraft. 

Since the grounding Boeing kept producing, though assembly was halted for five months. "Of those 470 stored MAXs, about 60 don't currently have a customer," stated Broderick, "but the airlines want them as they are more efficient than current models." The aircraft is even supposed to serve long-haul routes. Canadian carrier WestJet, for example, wants to deploy it on the North Atlantic.

Certifying the pilots of the future

First, all pilots currently certified for the 737 MAX have to go through additional training as soon as procedures, requirements and content have been confirmed by authorities. In total it will comprise five hours, of which two hours will be spent in a simulator and one in a briefing. At large airlines, this process can take months. American Airlines wants to qualify 1,700 pilots by December and train the remaining 2,500 by March 2021.

Second, specific focus has to be put not only on pilots at big Western airlines but also on those flying for airlines in other countries as the accidents, which happened in Indonesia and Ethiopia, prove. "They have to look more at global pilot standards and how they cope with the MAX philosophy. That is a lesson learnt," said Broderick.

Finally, there is the challenge for airlines to get their own staff and passengers to comfortably settle into the thought of flying safely now in the tarnished 737 MAX. "For some passengers, the problem of having to board a MAX might be more acute than the coronavirus," said Broderick.

American Airlines is already planning demo flights for staff and frequent fliers. MAX visits at airports and Q&A sessions with pilots and mechanics are being planned. European operators such as TUIfly in Germany also have plans to present the 737 MAX to the public as an aircraft that is (now) safe to fly.