Boeing Co. BA, +1.89% delivered 18 airplanes in August, the company said Tuesday. That compared with the delivery of 64 airplanes in August 2018. Boeing has delivered 276 planes so far this year, compared with 481 jets, or 43% fewer, in the same time span last year. Also Tuesday, the company said it is reviewing an incident related to a loading test for its 777X plane. Testing of the plane was halted after it reportedly lost a cargo door after an on-ground stress test over the weekend. On Tuesday, Boeing characterized the incident as involving a depressurization of the fuselage after the wings of the plane were bent “far beyond anything expected in commercial service,” and said it happened during a final on-ground test. “While our root cause assessment continues, at this time we do not expect that this will have a significant impact on aircraft design or on our overall test program schedule. We remain fully focused on safety as our highest priority, as we subject the 777X to a rigorous test program prior to first flight,” Boeing said. Earlier this week, The Wall Street Journal reported that Boeing’s 737 Max, involved in two fatal accidents in less than five months and grounded since March, could remain grounded through December. Boeing shares have gained 14% so far this year, compared with gains of 18% for the S&P 500 index. SPX, -0.54%