Its second-quarter net loss stood at $1.44 billion, the company said on Wednesday, compared with $149 million a year ago.
Boeing's Defense, Space and Security unit, one of its three main businesses, has lost billions of dollars in 2023 and 2022, which executives attributed to cost overruns on fixed-price contracts.
Such contracts have high margins but leave defense contractors vulnerable to inflationary pressures that have dented U.S. corporate earnings in the last few years.
The planemaker used to bid aggressively for fixed-price contracts before the pandemic, but has now said it would pivot away from such contracts to stem losses at the business, which amounted to $1.76 billion last year.
Ahead of last week's Farnborough Air Show, the unit's head had said it was "significantly challenged" during the quarter.
Boeing CFO Brian West said in May the planemaker will burn rather than generate cash in 2024, hamstrung by lower jet deliveries compared to last year.
The company is mired in crisis after a cabin panel on a 737 MAX 9 jets blew off midair in January, which led to a slowdown in production of its top-selling plane and a management shakeup, even as it came under intense regulatory and legal scrutiny.
The U.S. aviation regulator has capped production of 737 MAX jets at 38 per month, though Reuters has reported that Boeing has been producing jets during some weeks at a much lower level.
That has led to lower deliveries, frustrating customers. During the second quarter, Boeing delivered a total of 92 aircraft, down 32% from last year.
The company is searching for a new CEO to replace Dave Calhoun, who has decided to step down by year's end.
