A350-1000 | Loss of lift and specific flight condition

Greetings!

Before starting this topic, I want to make it clear that I'm not an expert and I don't know if my conclusion is correct, so feel free to add your knowledge to this thread.

Here we go... I was flying BAW248 between SAEZ and SBGL with the A35K. My planned cruising altitude was 41,000 ft. From the ground up to cruise level, the wind was around 2 kts. Once I leveled off at FL410, I remembered to adjust the wind speed according to the real flight plan from SimBrief. In this case, the forecast indicated a tailwind of 79 kts. Since Aerofly allows a maximum of about 39 kts, that’s what I set. I went back to the main menu and increased the wind speed to the maximum, as well as adjusted the direction to match the forecast. Then I jumped back into the flight and continued as normal...

A few minutes later, I heard the autopilot disconnect alarm. Along with it, there was an alert on the ECAM saying “ENG THRUST LOCKED,” and on the PFD it showed the aircraft had entered "A. FLOOR" mode (ALPHA FLOOR). This A. FLOOR mode is a stall protection that automatically activates to prevent the aircraft from losing lift.

Since A. FLOOR was keeping the aircraft flying, I decided not to address the loss of lift right away and focused first on the ENG THRUST LOCKED alert. I tried a few things based on my knowledge, but nothing worked. So I quickly searched ChatGPT about the ENG THRUST LOCKED alert, and according to it, this condition occurs when the aircraft loses the signal between the thrust levers and the FADEC. The recommended procedure was to move the thrust levers to idle for about 3 seconds and then move them back to climb or TO/GA. This should resynchronize the FADEC with the lever positions — but it didn’t work.

So I decided to exit A. FLOOR mode by diving to regain speed. After recovering, I climbed back to FL410 at the same planned speed, Mach 0.85. Everything was fine for a few minutes, but I noticed that the speed was gradually decreasing. I didn’t interfere — I just observed the aircraft’s behavior to try to understand what was going on. Eventually, the speed dropped enough for the aircraft to enter A. FLOOR mode again, and the “ENG THRUST LOCKED” alert showed up on the ECAM once more. I tried again to resynchronize the levers by moving them to idle and then to TO/GA, but it still didn’t work. So I dove again to exit A. FLOOR mode and climbed back to FL410. Since I was already close to TOD, the issue didn’t happen again. I began the descent and landed normally.

But I wasn’t able to solve the in-flight emergency or identify its root cause.

In discussion with a friend, we came to the following conclusion: the fact that I abruptly changed the wind speed and direction from 2 to 39 kts caused a “shock” to the aircraft when I returned to the flight, which made the FADEC lose synchronization with the thrust levers. And maybe due to some limitation of the simulator — after all, we’re talking about a mobile simulator — it was unable to resynchronize. Also, it’s worth noting that I was flying close to the aircraft’s maximum operational ceiling, which in itself puts the aircraft in a more sensitive flight envelope. Could we be right?

Another thought I had was regarding the lack of fuel consumption in Aerofly, which leads me to believe that the aircrafts have fixed and unchangeable weight and balance. If that’s the case, then maybe the A35K wasn’t designed with the correct weight and balance to remain stable during flights with strong tailwinds at very high altitudes, close to its operational ceiling. Please clarify if that’s how Aerofly works.

Thanks to everyone who reads and replies!

Quote from Jet-Pack (IPACS)

A disconnection is not simulated. The thrust locked indicates that the stall protection has activated and the current manual input is overwritten by the protection max thrust command.

The correct recovery from the stall is to reduce the angle of attack and to increase airspeed.

FL410 might be above the ceiling for the current weight, which is near Max landing weight. I'd recommend staying below FL390 and keeping the speed high for increased Mach ram air effect, which increases thrust. If you get too slow then you can only recover by diving down, which means loosing 5000ft or more.

I didn't know that the A35K's weight was set to something close to MLW. In fact, this must be preventing us from flying at high flight levels, which is a shame, because it is completely realistic to fly so high on short routes like SAEZ-SBGL and in the final legs of long-haul flights, which already consume a lot of fuel, and the step climbs programmed in SimBrief allow us to reach altitudes like FL390, 400, 410...
I am used to flying the B77W and have never been in situations like this. If it is also configured by the system with a total weight close to MLW (which is actually 30 thousand kilos more than the A35K), then this shows how impressive the power of the GE90 engines is, which deliver about 18% more thrust than the RR Trent XWB.
Does IPACS intend to add fuel consumption and its consequences on weight and balance in the future? What is the main challenge that prevents us from already having this in the simulator?