The Boeing 737 MAX 10 is facing an uncertain future with moves by US congressman Peter DeFazio to block an extension to the December 31, 2022, deadline for the aircraft's certification.

DeFazio, who appears in the Netflix documentary 'Downfall: The case against Boeing', leads the US House of Representatives Transportation and Infrastructure Committee.

He said on April 6 that he would oppose Congress extending the waiver it had granted to the MAX 10 program, adding,

"The aircraft certification bill gave the FAA a two-year grace period to certify aircraft without the advanced flight crew alerting system, but that grace period should not be extended."

Some big customers will want answers

Boeing's Orders and Deliveries report of 28 February, lists unfilled orders for the 737 MAX standing at 4,137 aircraft. Boeing does not break this total down by variant, although Bloomberg reported in March that Cirum data shows 568 MAX 10 on order.

United 737 MAX Lie Flat
United Airlines received its first Boeing 737 MAX in 2018 and has around 365 more on order. Photo: Getty Images

Boeing's report shows large 737 MAX orders from Southwest Airlines (382), United Airlines (365), Lion Air (237), flydubai (159) and Ryanair (156). A further 724 are listed for unidentified buyers.

Somewhere amongst those aircraft are orders slated for the MAX 10, so Boeing has some serious work ahead of it to get this issue sorted out and keep its large and loyal customers happy.

The FAA had previously warned Boeing in March that time was running out to get the MAX 10 certified before the deadline. In a widely reported letter, the FAA asks Boeing for a "mature certification schedule" and updates on the progress of the 737 MAX 10 and the 777-9 program.

What happens if the deadline is missed?

If the deadline is missed, Boeing faces costly disruptions and delays if it has to redesign the MAX 10 flight-control system to add a new emergency alerting system.

The reason for the pressure is that the 2020 Aircraft Certification, Safety and Accountability Act, passed by Congress in response to the Lion Air and Ethiopian Airlines MAX crashes, reformed how the FAA is to certify new aircraft types.

The law set the end of 2022 as the deadline for imposing new safety standards for cockpit alerts. Boeing was granted a two-year waiver to get the MAX 10 certified as it is designed to operate identically to the earlier MAX variants, which are now back in service.

As the lawmaker, it is up to the US Congress to amend the law to give Boeing more time for the MAX 10, although given DeFazio's stance that will not be plain sailing.

Ryanair, European Aviation, Recovery
Ryanair has around 156 Boeing 737 MAX on order and will be waiting to hear about the MAX 10 certification issues. Photo: Getty Images

DeFazio has fiercely criticized the planemaker, saying in his 2020 report that the MAX crashes...

"...were the horrific culmination of a series of faulty technical assumptions by Boeing's engineers, a lack of transparency on the part of Boeing's management, and grossly inefficient oversight by the FAA."

If Boeing is unable to get either the MAX 10 certified or secure an extension to its waiver it potentially faces millions of dollars in cost and years of delay. It would have to redesign the aircraft to comply with the statute passed by Congress that takes effect from the start of 2023.

The MAX 10 would basically be a new aircraft, containing different cockpit systems requiring more pilot training, adding cost and complexity to the airlines.

Conversely, the Airbus A321neo and the LR/XLR types have the MAX 10 covered, but with more than 3,000 in backlog getting hold of some in a hurry might be challenging.