Why were questionable, technically impossible operating parameters of the crashed Germanwings aircraft not examined?

Simultaneously set flight modes, which exclude each other; plus a newly implemented procedure to check the emergency code function of the cockpit door

Relevant data from an aircraft are stored on the cockpit voice recorder (CVR) and the flight data recorder (FDR). The cockpit voice recorder documents pilot voice communications as well as all cockpit sounds. The flight data recorder stores physical data, such as speed, altitude, etc., and  also pilot settings on the autopilot control panel FCU (Flight Control Unit).

The recorders from the crashed Germanwings aircraft were found on separate days and the stored data retrieved. Graphical representations of the parameters taken from the flight data recorder are documented in the French investigation file. Aviation experts and pilots have examined these graphs and analysed them for plausibility. There are striking anomalies regarding different parameters. For example, see the following excerpt from the French investigation file:

Objektiver_Befund_franz_Orginal_Band_03_Blatt 803-1202 (HA 00924)

The graphs show the two automatic flight modes DES (Managed Descent) and OPDES (Open Descent). It can be seen that during the descent the two automatic flight modes DES (upper graph) and OPDES (lower graph) were simultaneously active.

As several Airbus A320 pilots have independently confirmed, having both settings concurrently active is technically impossible. For the Open Decent (OPDES) the altitude adjustment knob must be pulled out. For the Managed Decent setting, the same altitude knob must be pressed in. And when it is pushed in, the other mode is automatically disabled. Thus, it is completely impossible that both setting modes could have been active at the same time.

Another example of an anomaly can be found in the recording of the modes CLB (Managed Climb) and OPCLB (Open Climbs). See the following excerpt from the French investigation file:

Objektiver_Befund_franz_Orginal_Band_03_Blatt 803-1202 (HA 00924)

According to the graph, these two were also simultaneously active in the period from approx. 09:19 to 09:24. This is, again, techinically impossible.

Open Climb means that the engines are running at maximum thrust for the climb and the piot has selected the speed. In the Managed Climb mode the aircraft follows a speed and altitude profile which was previously stored in the Flight Management System. Open Climb is instigated by pulling out the altitude knob and Managed Climb by pressing in the altitude knob.

To repeat, when the altitude knob is pressed in the other mode is automatically disabled. And again, it is technically impossible that both mode settings could have been active at the same time. It should be noted that shortly after takeoff (see graph) at approximately 09:02 only the Managed Climb function was recorded as activated, and not both modes simultaneously.

But there is also an example where Airbus and Lufthansa became active only after the Germanwings crash and its consequences: The verification of the keypad function for accessing the cockpit.

Since the Germanwings crash, the keypad of the cockpit door and the proper function of the cockpit door locking system must be checked by the pilot once daily by entering the emergency code. Shortly after the aircraft accident there were indications from Germanwings insiders that the keypad of the Germanwings crashed aircraft had already malfunctioned previously in an attempt to open the unintentionally closed cockpit door on the ground by entering the emergency code. The door would not open after entering the code and entering the cockpit was only possible with the aid of Lufthansa technicians.

Mr van Beveren already personally reported this incident to the BEA on 28.03.2015, and also  mentioned it in a telephone conversation with BEA spokeswoman Martine Del Bono. At the time he was acting as an independent aviation journalist to the BEA investigation authority. However, there followed no reaction or initiation of an investigation (see link, page 61).

https://andreas-lubitz.com/wp-content/uploads/2018/04/Expert-Report-on-the-Crash-of-Germanwings-Flight-4U9525.pdf

Previously, the proper functioning of the emergency code was checked procedurally by Lufthansa technicians only every 12,000 flight hours.

From the Germanwings cockpit voice and sound recordings it is not apparent that the captain entered the emergency code. This prompts the legitimate question of, why not?

Furthermore, it has not been recorded or documented that the cockpit door was locked since the take-off in Barcelona until the collision in the mountains. See also article:

The deliberate lockout of the captain from the cockpit – The investigation file itself shows that this was not the case

Finally, the question persists as to why the questionable operating conditions of the crashed Germanwings aircraft have not been sufficiently investigated and clarified to definitively rule out that these circumstances could have contributed to the accident.

L.U.

 

further article:

The deliberate lockout of the captain from the cockpit