737 MAX 7 and MAX 10 likely to be further delayed

The latest setback to the Boeing 737 MAX program is a load reduction device on the CFM LEAP engine that engages after engine damage from a bird strike.  In the event of a broken fan blade, a system engages to reduce the load on the engine by disconnecting the fan to reduce vibrations that could further damage the engine.  The system works well, and bird strikes with larger birds that the certification requirements have still resulted in the engines working as planned.

While all of that is well and good, the system also, unfortunately,  impacts the bleed air system feeding the cockpit and cabin air systems, and could result in noxious fumes being fed into the cabin through bleed air contamination.  The cockpit and cabin are fed from different engines, so this depends on which engine may have a bird strike. In two recent Southwest Airlines

incidents, cockpit air has been impacted from the impacted engines.

As this is a safety of flight issue, the FAA has convened a safety review board to assess the impact of the system, which will likely need to be redesigned prior to the certification of the MAX 7 and MAX 10.  In non-beltway speak, that means the problem is serious enough for the agency to take action to fix the system, and have pilots utilize alternative procedures as necessary during climb to avoid problems. This problem will be in addition to the engine anti-ice system issues that have delayed the certification of the two newest MAX variants, and we expect the FAA to take a similar position with this problem.