DL2639 SEA-MCO redeye diverted to Spokane April 8, 2017
 

Just noticed this. According to flightradar24, about 50 minutes into the flight, while cruising ~50 miles south of Missoula MT, DL2639 makes a U-turn and diverts to GEG (Spokane). Any ideas why? Medical emergency maybe? The plane was only on the ground at GEG for about an hour before continuing to Orlando, so mechanical seems unlikely. Also, why not divert to Missoula, which would have been a lot closer?

A medical emergency. Missoula only has one or two Delta gates, and it may have been occupied, or maybe it can't accommodate a B737-900 because it requires a tail-stand. If Missoula doesn't normally get 739s, then they wouldn't have a tail-stand to support the aircraft at the gate, and it could tip back.

I was unaware of the tipping issue, but that makes sense. Seems another option would have been BZN (Bozeman), where DL does regularly operate 739s to SLC and MSP. BZN is roughly the same distance from the diversion point as GEG, but would have allowed the flight to continue in the same direction instead of backtracking. I wonder if the time of day (or night) and the level of staffing on the ground at that hour had something to do with it?

If there had been a risk of the crew timing out, DL might have wanted to be closer to the SEA hub.

BZN's last arrival was at 9:56 PM (MDT).
MSO's last arrival was at 5:18 PM (MDT) (later flights were canceled).
GEG's last arrival was at 12:45 AM (MDT).

DL2639 arrived in GEG at 1:15 AM (MDT).
BZN and MSO were probably closed for the night when 2639 started to divert.

For a medical, as mentioned in the excellent City in the Sky series, the decision could rest on availability of appropriate experts/facilities.

True, but I wouldn't expect there to be significant differences in the quality of (emergency) medical care between these three airports. It's not like they diverted to Rochester MN.

Sookane has the regions only level 2 trauma center. While not trauma, number of other specialist needed conditions/equipment are most likely treated there also.

Somewhat unrelated to a flight diversion, but I find that dispatchers don't always make the most logical decisions under pressure. Back in my law enforcement days it took us ~45 min to evac someone with a life flight that I probably could have pulled off in 30 min with one of our vehicles.

That was my thought as well, but there is also a Level II center in Missoula. I can't think of any medical emergency that would be better served in Spokane than Missoula. I think the availability of crew and proper equipment is more likely the deciding factor in this case.

That's one of the bigger controversies in the EMS field - states and/or hospitals invest in helicopters. They are useful in some circumstances, but get overused to justify the investment. Dispatchers are likely following an established protocol and make the decisions for ground vs. air based on a combination of distance, type of injury/illness, and need for pre-hospital care, so their personal logic isn't a factor. You probably could transport a patient in the back of a patrol car faster than the helicopter (given the time it takes for the helicopter to arrive), but the flight EMS crew can provide a much higher level of care (i.e. intubation, IVs, continuous monitoring of vitals).

Sure, but I think the ambulance would have also been faster. I would have just helped with traffic :)