Absent terror activity, it looks like stall-spin to me.
Absent terror activity, it looks like stall-spin to me. A few reasons why it probably isn't:
- They haven't mentioned a stall warning or stickshaker activation yet. Both of these would be audible on the CVR and the shaker evident on the FDR.
- While it is possible to stall a plane at 250+ kts (you can stall a plane at any speed), it requires some pretty dramatic control inputs to do it.
- In stall-spin accidents, the aerodynamic forces on the plane are not severe. I have seen a lot of them, most of them small planes of course, but they are always intact with all components on the scene. Browse the reports at NTSB and you will notice a couple of stock phrases in these common accidents, including that "continuity of the control systems was established." Clearly wasn't the case here, because as the plane slammed into Rockaway one of the control surfaces was fluttering down to Jamaica Bay like a sycamore seed.
This is clearly a highly unusual accident... as is common with airline accidents, unlike small plane accidents where it is usually just the same old thing with new people involved (grimace). I almost included the rarity of airline stall/spin accidents in the list above, but this one is such an oddball that we can't use rarity or unlikelihood alone to rule things out -- we just have to be aware of what's rare and what's common, to keep our judgment tuned up.
Usually, on a Thursday after a Monday morning prang in a civilised place, you are starting to have a pretty clear picture of what happened. I haven't seen today's news yet but it seems as if we don't yet.
d.o.l.
Criminal Number 18F