Kriminell unzureichendes Handbuch für B737 MAX

Immer mehr Fluggesellschaften legen ihre neuen B 737 MAX-Flotten still. In ganz Europa, in Asien, Australien und Afrika besteht Flugverbot für die B 737 Max 8. Es besteht der Verdacht, dass eine Software zur Steuerung der Flugzeuge fehlerhaft arbeitet und zwei schreckliche Abstürze (Lion Air und Ethiopian Airways) verursacht hat. Die US-Luftfahrtbehörde FAA sieht noch keinen Anlass für ein Grounding der neuen Maschinen in den Vereinigten Staaten. Boeing indes ist sehr verunsichert. Nachstehend das Statement des Herstellers.

Bemerkenswert: Auch in den USA kritisierten Piloten die neue Steuerungssoftware MCAS (Maneuvering Characteristics Augmentation System) im Aviation Safety Reporting System. Drei Kapitäne und zwei Copiloten meldeten, dass die B 737 Max 8 während des Steigflugs ihre Nase plötzlich nach unten senkte und in den Sturzflug übergehen wollte. Sie konnten Schlimmeres verhüten, indem sie den Autopilot-Modus ausgeschaltet worden sei. Ein Eintrag besagt, die 737 Max 8 sei nicht ohne spezielles Trains zu fliegen. Und das Handbuch zur Bedienung des neuen Kurz-/Mittelstreckenjets sei „mangelhaft und fast kriminell unzureichend“. Bei Boeing versichern sie nach wie vor, das die 737 Max-Jets absolut sicher sind; sie wollen die Maschinen aber noch sicherer machen, was immer das heißen mag. Die US-Luftfahrtbehörde zögert noch mit einem Flugverbot, will erst die Ergebnisse des neuerlichen Absturzes abwarten. Aufzeichnungen des Ethiopian-Flugs zeigen, dass der Jet aus 3.000 m Höhe Flugzeugnase voran senkrecht mit über 700 km/h zu Boden stürzte. 

"The Boeing Company is deeply saddened by the loss of Lion Air Flight 610, which has weighed heavily on the entire Boeing team, and we extend our heartfelt condolences and sympathies to the families and loved ones of those onboard. 

Safety is a core value for everyone at Boeing and the safety of our airplanes, our customers’ passengers and their crews is always our top priority. The 737 MAX is a safe airplane that was designed, built and supported by our skilled employees who approach their work with the utmost integrity. 

For the past several months and in the aftermath of Lion Air Flight 610, Boeing has been developing a flight control software enhancement for the 737 MAX, designed to make an already safe aircraft even safer. This includes updates to the Maneuvering Characteristics Augmentation System (MCAS) flight control law, pilot displays, operation manuals and crew training. The enhanced flight control law incorporates angle of attack (AOA) inputs, limits stabilizer trim commands in response to an erroneous angle of attack reading, and provides a limit to the stabilizer command in order to retain elevator authority. 

Boeing has been working closely with the Federal Aviation Administration (FAA) on development, planning and certification of the software enhancement, and it will be deployed across the 737 MAX fleet in the coming weeks. The update also incorporates feedback received from our customers. 

The FAA says it anticipates mandating this software enhancement with an Airworthiness Directive (AD) no later than April. We have worked with the FAA in development of this software enhancement. 

It is important to note that the FAA is not mandating any further action at this time, and the required actions in AD2018-23.5 continue to be appropriate. 

A pitch augmentation control law (MCAS) was implemented on the 737 MAX to improve aircraft handling characteristics and decrease pitch-up tendency at elevated angles of attack. It was put through flight testing as part of the certification process prior to the airplane entering service. MCAS does not control the airplane in normal flight; it improves the behavior of the airplane in a non-normal part of the operating envelope. 

Boeing’s 737 MAX Flight Crew Operations Manual (FCOM) already outlines an existing procedure to safely handle the unlikely event of erroneous data coming from an angle of attack (AOA) sensor. The pilot will always be able to override the flight control law using electric trim or manual trim. In addition, it can be controlled through the use of the existing runaway stabilizer procedure as reinforced in the Operations Manual Bulletin (OMB) issued on Nov. 6, 2018. 

Additionally, we would like to express our deepest condolences to those who lost loved ones on Ethiopian Airlines Flight 302. A Boeing technical team is at the crash site to provide technical assistance under the direction of the Ethiopia Accident Investigation Bureau and U.S. National Transportation Safety Board. It is still early in the investigation, as we seek to understand the cause of the accident." Quelle: Boeing / DMM