Boeing tests MAX 7/10 anti‑ice update

Boeing has started formal flight tests of a redesigned engine anti-ice system on the 737 MAX 10, moving the delayed MAX 7 and MAX 10 deeper into certification. (theaircurrent.com) The engine anti-ice system sends heat to the front of the engine to keep ice from building up, like a car defroster for the inlet. The problem on the MAX was that using it in dry air for too long could overheat internal inlet structure. (federalregister.gov) The Federal Aviation Administration responded in August 2023 with an airworthiness directive covering 737 MAX jets with LEAP-1B engines. It said anti-ice use in dry air for more than five minutes in certain conditions could push the engine inlet inner barrel beyond its design limit. (federalregister.gov) That issue became one of the main reasons Boeing’s smallest and largest MAX variants missed earlier certification targets. The new test campaign is being flown on Boeing’s lead MAX 10 test aircraft, according to people familiar with the program. (theaircurrent.com) Boeing said on April 22 that it expects certification of the 737-7 and 737-10 in 2026, with first deliveries in 2027. The company also said the MAX 10 had begun Type Inspection Authorization 2 work in the first quarter. (investors.boeing.com) Federal Aviation Administration Administrator Bryan Bedford said on April 21 that the agency had not seen anything that would block certification before the end of 2026. He also said flight testing was still continuing. (bloomberg.com) At the same time, a separate safety issue is still running on another part of the 737 MAX engine system. A U.S. Department of Transportation inspector general report said the Federal Aviation Administration should do more to address a smoke-and-fumes risk tied to the LEAP-1B engine’s load reduction device after bird strikes. (flightglobal.com) (spokesman.com) The report said two Southwest Airlines 737 MAX flights suffered bird strikes that damaged an engine fan and triggered the device, allowing oil to hit hot engine sections and send smoke into the cabin or cockpit. CFM International is developing a software update intended to close a valve after the event and reduce fumes. (flightglobal.com) The inspector general said the software is expected to win aircraft-level approval in the third quarter of 2026, with full fleet installation not projected until mid-2028. The Federal Aviation Administration said it intends to adopt the report’s recommendations. (flightglobal.com) So Boeing’s path for the last two MAX variants now runs on two tracks at once: proving the anti-ice redesign in the air, and clearing fresh scrutiny over engine-related smoke risks. (theaircurrent.com) (flightglobal.com)