Amid great scrutiny and pressure from politicians and the media, Boeing withdrew its request for an exemption made to the FAA (Federal Aviation Administration) for the 737 MAX 7 to be certified without reviewing the engine inlet de-icing system.
The change is expected to further delay the type certification of the smallest of the 737 MAX family jets.
Now, Boeing will need to develop, test and approve a device that prevents the carbon fiber inlets from heating up to the point of breaking the nacelle and scattering debris across the fuselage.
The problem was discovered by Boeing after the 737 MAX 8 and 9 entered service and is considered extremely unlikely.
The new generation of commercial jets have composite intakes instead of aluminum and the de-icing system can overheat as the plane is flying in a dry, hot environment.
The solution accepted by the FAA was that the deicing system cannot be left on for more than 5 minutes and always turn it off as soon as the aircraft leaves the icy air.
Southwest Airlines postpones aircraft entry into service again
Boeing intended for the 737 MAX 7 to follow the same recommendation until 2026 while it does not develop a definitive solution, but manufacturing problems found in the 737 MAX 9 have put the company under pressure.
The new delay has already caused Southwest Airlines, the 737-7’s largest customer, to postpone plans to have the aircraft until 2024. Until then, the carrier had hoped to put it into service in the last quarter.
The variant’s launch customer, Southwest has 302 firm orders for the 737 MAX 7.