According to the New York Times on January 5, just as Boeing is trying to fly the Boeing 737 Max back to the blue sky, the new problems found on the aircraft have far exceeded the software problems in the two fatal air crashes. Boeing and regulators carefully examined all aspects of the aircraft and found new potential design defects.
According to a senior engineer of Boeing, at the request of the Federal Aviation Administration, Boeing conducted an internal audit last December. The most urgent problem found was the wire problem at the tail of Boeing 737max, which is a newly discovered problem. Boeing is studying whether the two critical lines at the tail of the aircraft are too close, which may lead to a short circuit.
Boeing found that if the two wires near the tail of the aircraft were short circuited, it could cause the aircraft to crash. These two wires are connected to the motor controlling the stabilizer, that is, the horizontal fin at the tail of the aircraft, and send a signal from the flight control computer to push or lift the nose down.
Boeing senior engineer said that once the wire is short circuited, if the pilot does not realize the problem and take prompt measures, the aircraft may dive and crash, just like the two crashes caused by the 737max aircraft maneuverability enhancement system (MCAS).
It is reported that Boeing informed the Federal Aviation Administration of potential vulnerabilities last month. In addition to the 737max series, it is also necessary to investigate whether the 737 ng has the same problem. At present, about 6800 of these types of aircraft are in service.
People familiar with the matter said that Boeing is still studying the possibility of short circuit of wires and the need to separate the lines on about 800 737max passenger planes that have been manufactured. Boeing does not want to change the aircraft's circuit unnecessarily, fearing additional damage during maintenance. Boeing said that if necessary, the repair of the problem is relatively simple.
Boeing also recently informed the Federal Aviation Administration that they found another quality problem that made the 737max aircraft engine vulnerable to lightning strikes. When assembling the max airliner, Boeing's plant in Renton, Washington, ground the panel on the engine housing to facilitate installation. But this inadvertently removes the coating that protects the panel from lightning. The Federal Aviation Administration is developing a directive requiring Boeing to restore the lightning protection coating on engine panels. Boeing is solving this problem.
New problems emerge one after another, bringing multiple challenges to Boeing's leadership. 737max aircraft is the most important aircraft of Boeing, with a global order of about 5000. But as the grounding intensified, Boeing said it would temporarily close its 737 plant, affecting thousands of suppliers.
It is reported that the Boeing 737max may be approved for certification test flight at the beginning of this month, which will be the final examination of the aircraft by the regulatory authorities and one of the last obstacles for the regulatory authorities to lift the flight ban on the 737max aircraft. American Airlines and Southwest Airlines plan to resume commercial flights of 737max aircraft in April, and United Airlines plans to resume the use of 737max in June this year.