Wall Street Journal: the pilots didn’t speak to air traffic control much during the descent – if it was an emergency descent for depressurization, they were probably talking to each other, making sure they were managing the descent. Good video there too.
@AviationSafety tweets the vertical profile. It’s consistent with a controlled, albeit steep descent averaging more than 3,000 fpm (38,000 ft to approximately 6500 ft in 9m47s). In other words, an emergency descent profile.
Marin Medic, over at Russia Times, complains that the A320 is a “nanny plane” that is easy to fly, interfering with pilot inputs to keep the plane from, say, stalling. For example, like this plane … That objection is meaningless – he also speculates that this was an emergency descent due to a depressurization. In terms of its flight envelope, this aircraft was always in the heart of it.
If the initial speculation of a controlled descent is proven accurate (it’s too soon to tell while the black boxes remain unexamined), then Controlled Flight Into Terrain (CFIT) is a player. They began the descent over low terrain (or water), and never deviated from a course that took them over the Alps. Maybe they were caught up with the descent and didn’t think about their proximity to dirt until the “pullup, terrain” call from the Ground Proximity Warning System. If so, then the tape is going to be a chilling listen.