Looks like initially they could have gotten a much tighter circuit to land but asked for delay vectors, then came back when the 2nd engine started to overheat. ATC cleared a company plane out of the way at first (and almost got an airprox between the company 809 and the emergency aircraft as she at first did not realize the emergency.
Do we know if they had a dual engine failure or if they just got a serious overheat/fire that led them to shutdown?
“Volcanic ash“
That would have been a global first. No aircraft has ever been brought down by volcanic ash. The only one that came close was 39 years ago and everybody still refers to that particular incident when talking about how dangerous VA is.
huv wrote:
“Volcanic ash“That would have been a global first. No aircraft has ever been brought down by volcanic ash. The only one that came close was 39 years ago and everybody still refers to that particular incident when talking about how dangerous VA is.
Im pretty sure that as a DIRECT result of that steep learning curve, Volcanic ash cloud is such a no-go area that there has been at least one CAT shut-down as a result… Id say that lack of fatal incidents is a good thing… 
Was that the British Airways one where they lost all engines and the crew had to look for an airport to which they could glide before engines were restarted having lost IIRC 20,000ft?
I would consider that in the nearly brought down category if not" brought down" in the literal sense.
It lost 3 engines, but could not hold altitude on just one, IIRC. Then 2 others came back… The info is all out there. It did get close 
In my Q above I wondered if the 737 has a single point of failure, other than volcanic ask / birds / fuel or other icing / bad fuel. The fuel systems are separate (one wing per engine) so if the fuel is good that cannot shut down both. BA038 got iced up on both but this could not be icing.
Could be a defective service action involving both engines, but I am informed by a current service guy that this is never supposed to be done.
Peter wrote:
It lost 3 engines, but could not hold altitude on just one, IIRC. Then 2 others came back…
It did lose all four engines. After descending to about FL130, the crew succeeded in restarting first one, then successively all the remaining engines. One of the engines had to be shut down later.
The info is all out there.
Yup.
Overheating and loss of thrust on the JT8 has already been reported after a thermal fatigue failure of the HP turbine distributor. When the distributor fails it takes out (part of) the HP turbine blades which causes an instant loss of rpm and therefore thrust. Loss of proper exhaust flow through the HP turbine causes the EGT overheat annunciation (and can melt whatever is left of the LP turbine).
Loss of the other engine can be totally unrelated.
huv wrote:
That would have been a global first. No aircraft has ever been brought down by volcanic ash.
Well, there were two near cases. Both recovered because they managed to get out of the volcanic ash. Had the ash concentration persisted to the ground, they would have crashed.
One was BA009, the lesser known one was a KLM 747 over Alaska.
While this is not totally impossible near Hawaii, I doubt it. Why? Because there was ample traffic in that area and nobody else has problems.
And while we have no information whatsoever, as a baseless speculation I am reminded of a 737 which crashed after one engine malfunctioned but the other one was shut down.
Volcanic Ash
“Ladies and gentlemen, this is your captain speaking. We have a small problem. All four engines have stopped. We are doing our damnedest to get them going again. I trust you are not in too much distress.”
- Captain Eric Moody
And now imagine some beancounter taking away his salad from the crew catering to save some pennies. Well, he probably skipped the green stuff and went for the steak right away anyhow. Those were the days.
