1 Did you see this, posted by someone on the plane?
https://path.com/p/1lwrZb
It may be that the plane flared too much, and the tail clipped the end of the runway. 

2

Yeah, that one's been around a lot already.

If the pilot blew the approach and dragged the tail on the ground or hit the end of the runway with it, that could cause the tail to come off.

3 From the aerial TV shots, it looks like the tail sheered off behind the passenger compartment.  The backup flight crew should be somewhere else for take-off/landing, I would think.  I pray no deaths, but there might be a few.

The NTSB is going to have a wacky time figuring this one out.  It really does look like the entire Tail just sheared off, which is quite odd.

4 Current word is 2 dead, 61 injured. Which is blessedly light for a jet crash, but still a tragedy. And the numbers are likely to change.

5 Early word is that it landed short/caught it's landing gear on the sea wall, given where the contact points seem to be. 

Would explain why the fatalities and injury numbers should stay low, blessedly, as it was on final approach and actually going quite "slow".  But the real blessing is the fuselage didn't roll, with snapped wings.  So this is more "bad car crash" levels of injury, rather than triple flip car crash injuries. 

The interesting bit is going to be why this happened.  It landed well short of the runway, so something went pretty wrong.

6 How in hell do you have the tail fall off the plane?

Writing from the future, the plane's tail hit the breakwater short of the runway.  The gear came off afterwards, as did the tail from the strike.

As far as the last major air crash in this country goes, it depends on what you consider "major".  If you mean "large plane," it'd be January 15, 2009: US Airways 1549, when an Airbus A320 put down in the Hudson.  If you mean "big plane, loss of airframe with big death toll", then you have to go back to 11/12/2001:  AA587.

7 I would bet on Taiwanese flight crew not being proficient enough to fly a jet as big as 777 without PAPI or ILS, as both were NOTAM-ed off for runway 28L. Doing it in a jet requires a certain mental calculation as you divide height over the field against the distance remaining (roughly the center of the field minus half of runway length). It is rather easy to do if you're in a habit, but suspect some of the heavy drivers may be too used to just keeping needles in the center. The weather was benign: clear, slight wind from 70 left (210@06).

BTW, according to FlightAware, the jet was slowing down hard on short final. Only was going 106 knots when 200 ft up. If that data turns out to be correct, he's gotten on the back of the power curve for some reason and sunk.

8 Much like F1's and Indy cars, Aircraft are designed to come apart in certain areas before others in an effort to absorb energy and make crashes more survivable, although the force required to make such a separation happen is guaranteed to happen only in the event of actually hitting something.  So, for example, the vertical fin and horizontal stabilizers would part company from the aircraft only to prevent taking any more of the structure with them, and the hydraulic connections as well have special breakaway fittings that would keep the rest of the hydraulic system functioning. (It's kind of odd reading those placards while putting in inch and a quarter bolts torqued to inch-TONS that hold the fin on. Trust me, you're gonna have to fly an A380 into that tail to knock it off.).

The next stage would have the tail cone break off leaving the pressure dome at the end of the fuselage intact, which is what appears to have happened here.  Likewise engine nacelles are designed to break off so as to avoid tearing off the wings, which would result in spilled fuel.  The luggage compartment is also a crushable area, which also seems to have happened here. There's also a lot of crushable air conditioning equipment between the belly of the plane and the center wing fuel tank.

It appears that everyone was off before the fire broke out that melted the top of the passenger compartment.

Some people fault those who got off the plane and then snapped pictures of the wreck they just walked away from, but what would they have them do? Interfere with the professional rescue crews?

9 Oh, and Pete, thanks for confirming what I'd heard elsewhere in only one place, that the ILS was off.  That was probably a major contributing factor.

10 So the smart money bets on cockpit error, eh?

11 Yeah, sadly.  Still, a miraculous outcome.

12 In a gruesome detail, an emergency vehicle ran over one of the two Chinese girls, although she was probably already dead from smacking the runway. Miracle for everyone else, however. NTSB already posted pictures of the interior and it's clear that some seats jumped their tracks. At least one mother reportedly carried out her kid who broke a leg, so not everyone was fully mobile. Also, a stewardess was pinned by an emergency slide that deployed inside instead of outside. Fortunately, someone helped her before the interior burned.