Adding to Boeing's pain, demand for its bigger and more profitable jet - the 787 Dreamliner - has waned in the face of the US-China trade war, prompting the company to cut production, hurting cash flow at a time when its debt is mounting.
The company posted its first annual lost in more than two decades, halted production of the top-selling MAX as the grounding of aircraft has dragged on, and on Wednesday announced it would again cut production of its 787 Dreamliner.
Boeing said last week it did not expect the MAX to return to service until mid-2020 and, given Ryanair does not take deliveries during its summer peak of June-August, it will not have the first 10 MAX planes until the autumn.
Rising costs from the grounding of its once-bestselling 737 MAX jets have left United States aerospace giant Boeing with its first annual loss in net revenue since 1997.
It was the first annual loss since 1997, when Boeing was roiled by parts shortages, production delays, and expenses from merging with McDonnell Douglas.
In October, Boeing lowered 787 production to 12 from 14 a month, citing lower orders from China.
Mr Calhoun said the crashes and resulting scrutiny from regulators mean the Max will be "the safest aircraft ever flown". Boeing expects to incur further costs in 2020 that will factor into the $18.4 billion, primarily due to production snags. Analysts had anticipated a much larger accounting charge after Boeing endorsed more rigorous training for Max pilots earlier this month and pushed its timeline for the plane's return back by about six months.
General Electric Co plans to slash 737 MAX engine deliveries to Boeing roughly in half this year. "I'm not going to market my way out of this", Calhoun told CNBC.
Boeing stock rebounded slightly on the quarterly report after suffering its deepest decline since the MAX grounding last March earlier this month. Even though 737 MAX production is being temporarily suspended, Boeing is keeping its workforce intact.
Calhoun called the messages "horrible" and criticized company leaders who didn't disclose the messages right away.
Revenue tumbled to $17.9bn, far below Wall Streets forecast of $21.7bn, according to a FactSet survey of analysts.
Boeing set aside another $9.2bn to cover the costs of airlines that have cancelled thousands of Max flights and towards higher costs related to compensation - doubling its estimate of the total financial hit from the crisis to $18.6bn.
During a conference call with analysts, Calhoun said he was "optimistic about the future". Shares rose 2.3% to $323.74 in afternoon trading.