Boeing’s monthly 737 MAX deliveries dropped to their lowest level in more than two years in September, as it addresses a manufacturing problem, according to company figures released Tuesday. The aviation giant sent just 15 of the top-selling jets to customers last month, the fewest since August 2021, according to figures on Boeing’s website. Boeing’s third-quarter MAX deliveries fell 26 percent to 70 compared with the year-ago period. The drop was offset by a more than doubling of 787 Dreamliner deliveries over the same timeframe. Airplane deliveries are closely watched by investors because they are tied to company revenues. In recent years, Boeing has been repeatedly forced to slow or suspend deliveries on the MAX and the Dreamliner — its two top-selling planes — as it struggled with production and quality control problems. Boeing has described the latest MAX issue as the result of misshapen holes drilled in a part of the fuselage that helps maintain plane pressure. The company maintains that there is no immediate safety of flight concern. Boeing supplier Spirit AeroSystems said in August it had implemented manufacturing changes and was working with Boeing on “needed rework” to address the issue. In a September appearance at a Wall Street conference, Boeing Chief Financial Officer Brian West said fixes were “more involved” than in some cases, involving extensive inspection. “We’ve got literally armies of people from Boeing and the supplier working on this issue and to drive stability in their factory,” said West. At the September event, West signaled that the repair would slow near-term deliveries. But he added that this would not prevent the company from reaching its medium-term target of monthly deliveries of 50 MAX planes in the 2025-26 timeframe.