Boeing said Wednesday that it lost $1.24 billion in the first quarter as it and took large write-downs and lost money in both its civilian-airplane and defense businesses.

The loss was bigger than Wall Street had been expecting and the company's quarterly revenue was also short.

Shares of Boeing Co., based in Chicago, fell almost 4% before the opening bell Wednesday.

Boeing offered some optimism for improvement, however, saying that it has submitted plans to resume deliveries of its 787 airliner and it increased production and deliveries of the 737 Max passenger jet during the quarter.

CEO David Calhoun said the company was on track to generate positive cash flow over the entire year.

Boeing's commercial-airplanes division lost $859 billion, hobbled by the inability to deliver 787 jets while Boeing tries to fix production flaws on the twin-aisle plane.

The defense business, long a bulwark against volatility in aircraft sales to airlines, lost $929 million as revenue fell 24%.

The company said its core loss per share was $2.75 a share on revenue of $13.99 billion. Analysts expected a loss of 25 cents per share on revenue of $16.02 billion, according to a FactSet survey.