3 ms·

This seems to be attributed to a technical problem and not turbulence so far. Probably should be a bit skeptical about any explanation this early, but I'm wonde

This seems to be attributed to a technical problem and not turbulence so far. Probably should be a bit skeptical about any explanation this early, but I'm wondering which systems would be powerful enough to cause something like this. For example, would a pilot be able to manually fly the airplane and cause this kind of incident? Or would the control surfaces of the plane be able to cause this assuming that any safety limits that restrict movement were not working?

H8crilA 3y ago
It's very easy to get to slightly below 0g by just pushing on the stick or yoke, and that would be enough to cause what the passengers describe here. You could even get well below 0g. Almost all turbulence of the sort that you can experience in flight are not even 10% of the durability limits of the airframe. EDIT: I was also thinking about "well why should the airplane allow the pilot for such movements then?". And I think a good analogy is the brakes in your car - they do allow for maximum breaking, yet when was the last time you actually pushed it to the max? (And note that this is 100% speculation, I just wanted to highlight that the pilot can cause such negative acceleration on their own)
- xattt 3y ago
  What about flight laws/flight control modes that prevent this thing from happening? Unless the aircraft was flying in a degraded state, these limits are supposed to prevent the aircraft from suffering damage during flight.
  - Vecr 3y ago
    It's a Boeing, that's not really how it works. What airplane refuses to let you do negative gs anyway?
    - p_l 3y ago
      Both 777 and 787 are full fly by wire, with the latter being unstable without computer help due to trimming of control surface sizes for greater fuel efficiency.
      - Vecr 3y ago
        For some reason I didn't think it switched laws, it was just on or off. Maybe that was for the 777 instead?
  - icegreentea2 3y ago
    Briefly going slight negative G will not damage the airplane.
stby 3y ago
If the captain of this LATAM flight didn't report that all systems went down for a short while, I'd bet some money on a malfunctioning ADIRU [0]. The Wikipedia page even includes a nice list of incidents caused by it, mostly with similar results. [0] https://en.wikipedia.org/wiki/Air_data_inertial_reference_unit https://en.wikipedia.org/wiki/Air_data_inertial_reference_un...
j-a-a-p 3y ago
> would a pilot be able to manually fly the airplane and cause this kind of incident? As a parent and car pilot I used my brake once to teach my children the necessity of wearing seatbelts. You actually do not need to break hard to let them fly around I noticed.

H8crilA 3y ago

It's very easy to get to slightly below 0g by just pushing on the stick or yoke, and that would be enough to cause what the passengers describe here. You could even get well below 0g. Almost all turbulence of the sort that you can experience in flight are not even 10% of the durability limits of the airframe. EDIT: I was also thinking about "well why should the airplane allow the pilot for such movements then?". And I think a good analogy is the brakes in your car - they do allow for maximum breaking, yet when was the last time you actually pushed it to the max? (And note that this is 100% speculation, I just wanted to highlight that the pilot can cause such negative acceleration on their own)

xattt 3y ago
What about flight laws/flight control modes that prevent this thing from happening? Unless the aircraft was flying in a degraded state, these limits are supposed to prevent the aircraft from suffering damage during flight.
- Vecr 3y ago
  It's a Boeing, that's not really how it works. What airplane refuses to let you do negative gs anyway?
  - p_l 3y ago
    Both 777 and 787 are full fly by wire, with the latter being unstable without computer help due to trimming of control surface sizes for greater fuel efficiency.
    - Vecr 3y ago
      For some reason I didn't think it switched laws, it was just on or off. Maybe that was for the 777 instead?
- icegreentea2 3y ago
  Briefly going slight negative G will not damage the airplane.

stby 3y ago

If the captain of this LATAM flight didn't report that all systems went down for a short while, I'd bet some money on a malfunctioning ADIRU [0]. The Wikipedia page even includes a nice list of incidents caused by it, mostly with similar results. [0] https://en.wikipedia.org/wiki/Air_data_inertial_reference_unit https://en.wikipedia.org/wiki/Air_data_inertial_reference_un...

j-a-a-p 3y ago

> would a pilot be able to manually fly the airplane and cause this kind of incident? As a parent and car pilot I used my brake once to teach my children the necessity of wearing seatbelts. You actually do not need to break hard to let them fly around I noticed.