After the Alaska Air 737 MAX-9 blowout, more certification delays could hit the MAX-10, forcing United Airlines to consider alternatives.

“I think the MAX 9 grounding is probably the straw that broke the camel’s back for us…”

The above statement came from United Airlines CEO Scott Kirby, during a CNBC interview on Tuesday. His airline still has orders for around 390 737 MAX single-aisle aircraft. Of these, 277 orders are for the larger 737 MAX-10, and United also has 200 options for the same type.

United Airlines was a launch customer for the 737 MAX-10, converting some MAX-9 orders to the type, back in 2017. More orders came in 2021 and 2022. Initially, Boeing and many analysts saw the MAX-10 as a stretched, high-density 737, that would attract interest mainly from low-cost carriers.

But the jet attracted orders from other airlines, users of the 737-900ER and MAX-9. The MAX-9 hasn’t actually been a very strong seller for Boeing. Initially, the smallest MAX-7 seemed to be the MAX variant that would attract the fewest orders.

Repeat MAX-7 orders from Southwest and some more recent orders by Allegiant, changed that. But the bigger MAX-9 has made reasonable sales in the United States. U.S. carriers fitted it with enough premium seats that its capacity is comparable to that of most European MAX-8s. Hence the need for fewer active exits, and therefore that door plug.

United Airlines: A Long Wait For the 737 MAX-10

Existing certification delays for the 737 MAX-10 meant that United and other airlines continued picking up the smaller MAX-9, rather than convert orders to the larger variant. When it enters service, the MAX-10 will have a mid-cabin exit door design similar to the MAX-9.

However, these will be active doors, NOT door plugs. Even so, the certification of this variant faces the same question marks as the smaller MAX-7. Specifically, Boeing needs a waiver, to deal with a potential overheating issue, in certain conditions, involving the engine nacelles and the engine anti-ice system.

Boeing needs to design and retrofit a modified nacelle and engine anti-ice system to all 737 MAX aircraft by 2026. The American manufacturer wants a waiver allowing it to certify the MAX-7 and MAX-10 with the current nacelles. However, recent events make this increasingly unlikely.

Without a waiver, Southwest and United won’t start taking delivery of their MAX-7 and MAX-10 jets respectively, until the modification is ready – in 2026. For United, the MAX-10 is already 5 years late. Until this month’s events, United expected to take the first deliveries of the jet in 2025.

Now, Scott Kirby says that United will have to start planning for the possibility that its future fleet won’t have the 737 MAX-10 in it. Deliveries of MAX-9s have been slow thus far, and the blow-out won’t make them any faster.

Frustrated, Disappointed, Angry

Kirby added that he has confidence “in the people of Boeing”, including mechanics and engineers, making no mention of management. He said he is “frustrated and disappointed.” In a separate interview, Alaska Airlines CEO Ben Minicucci expressed similar sentiments, saying:

“I’m more than frustrated and disappointed. I am angry. This happened to Alaska Airlines. It happened to our guests and happened to our people. And – my demand on Boeing is what are they going to do to improve their quality programs in-house.”

Boeing doesn’t really have a workable alternative to the MAX-10, but realistically, neither does United or other airlines. Orders for the A321neo would certainly do nicely, in theory. But in practice, the delivery dates for new A321neo orders could go beyond 2030. Without the MAX-10, Kirby acknowledges that United will have to grow its fleet slower.

Later this week, Boeing CEO Calhoun will meet several U.S. Senators, to answer questions over the Alaska MAX-9 accident and subsequent discoveries of loose fittings in other aircraft. The Senators are expected to ask Calhoun how he can restore the public’s confidence in Boeing.

Since the latest accident, Boeing has actually secured an order for 150 737 MAX aircraft to Akasa Air in India. But closer to home, Boeing still has a lot of convincing to do. The orders that United alone has for the MAX-10 represent about a quarter of the backlog for this 737 variant. A cancelation like this could trigger multiple events.

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