Watched a top notch jet pilot explain the whole thing. Looks like some blame MIGHT be with air control.
None.
The cause was heavy icing.
Dropped him right down into a severe thunderstorm with heavy rain,
ATC doesn't monitor weather on the screens.
The aircraft was climbing with light to moderate icing conditions when it flew through the storm cell and suddenly encountered very heavy icing conditions.
Ceiling. No, it wasn't. That storm's base cloud was no more then 1000 ft.
...plane iced up and couldn't get lift when he made his turn.
He was not trying to turn. One wing dropped before the other, putting her into an uncontrolled spiral and loss of control.
Listened to the whole pilot/ traffic control tape,....horrible. Those poor souls.
Yes. The pilot knew the plane was doomed. There is no way to recover from such a loss of control due to icing in that kind of plane.
By the time the plane hit the ground it was overspeeding and almost inverted.
In something slower like a piston aircraft, there MIGHT be enough time for the ice to thaw (they tend to be high drag and slower flyers)...but it's dicey.
That model of Learjet does have anti-icing equipment, but it can only handle light icing conditions. The storm core created very heavy icing conditions suddenly, beyond the capabilities of the equipment on board to cope with it.
Some planes install weather radar to look out for such storms so they can be avoided. I don't think this jet was so equipped. It's not common on Learjets.
Some times ATC does everything right, the pilot does everything right, but a storm comes up to smite thee.