Delta Goes Big, Then Goes Home

Let me explain, the metar and tafors (the airport meteorological reports we use) during the flight in San Juan show that the flight was doable. No crazy winds during landing, and worsening during take of but well within the limits you may find in a local thunderstorm. The predictions allowed them to see the window to fly in and out. If arriving the weather was too bad or you see the hurricane getting too close to the airport,they could have got away without landing. For take off either you have the right conditions (under the legal limits) or you don't.

What they risked IMHO is having some kind of technical problem or delay once in San Juan and having to stay there to weather the hurricane. That could mean heavy damage to the airplane while on the airport, even a total loss.

That said for me the most amazing of it all, is not the short stay at the ground. While very fast is not uncommon to see them with an experieced team, the slower part is the disembarking and embarking of the passengers, and they surely were all motivated to hurry.

The most impressive is how they followed the quite thin alley between the hurricane arms till they were clear of the bad weather. In a situation like that you only see red and magenta in your radar and a narrow black or green zone where you can fly safely. That's surely was the most scary part for them beyond the adrenalin of a fast and potentially dangerous operation.

Looks like the typical movie scene of a spaceship passing between closing doors!! Certainly brass balls.

Edit: some typos and a "don't" that I left behind and was changing the meaning of a sentence. Sorry written from the cellphone.

The older bombers they flew were all manual controls (as opposed to fly by wire), which meant physical exhaustion from wrestling the plane into the storm was a major factor - so they'd bring extra fuel to be able to circle the eye of the storm for some amount of time to build up the strength to fly back out.

- On August 24 Typhoon Hato hit HongKong hard. All airlines canceled their service in and out of HKIA, except a lone KLM flight from Amsterdam. Similar to the delta flight into San Juan, this flight created a large media storm into the risk involved. http://liveandletsfly.boardingarea.com/2017/08/24/klm-747-ty...

While I am not a pilot, I know that such flights involve sophisticated planning (route, fuel, approach), weather prediction as well as diversionary plans if things do not work out. No airline would undertake such a high-risk move without the confidence that they are not putting lives at risk.

I can't image what it must be like to fly into a storm system like that. Nerves of steel.

1) Hurricanes are actually harmless to planes. The only part of the flight that includes any danger is landing, due to wind and low visibility. But flying at cruising altitude or even through the storm is fairly harmless, as most winds are horizontal and nothing out of the ordinary for a plane. Keep in mind that the NOAA regularly flies commercial jets (such as a Gulfstream V) into hurricanes. Also keep in mind that never in the history of aviation has a plane been brought down by a cyclone. Thunderstorms, on the other hand, are much more dangerous. The main difference is that in a cyclone, air moves horizontally, while in a thunderstorm it moves vertically in bursts, which is much more difficult to navigate.

2) From what I've heard, this was not a commercial flight but a flight mainly aimed at evacuating non-rev airline employees. The main issue with doing this flight for regular passengers would be fear and discomfort due to turbulence. Airline employees on the other hand are used to flying, know that turbulence is harmless, and would rather just get home.

What are the odds something could go wrong compared to the relative good of squeezing in one last flight's revenue for a while? Is flying in a hurricane actually not that bad and the airport turnaround/takeoff the most dangerous part?

I wonder, is this a good (and incredibly positive) example of what quality real-time/near-real-time data can do for decision-making?

Bravo.

There are probably at least some NTSB human factors specialists cringing at this.

Anyone with knowledge of this?

Bona fides: FAA Licenced Aircraft Dispatcher; 11 years industry experience. (Left the industry in 2000) Staff title: Chief Dispatcher

Preface: I'll not attempt to address the many meteorological or airframe engineering aspects of this mission other than to note that Delta staffs its own meteorology department (or did last I was privy to their operations). The capabilities that lend to the carrier are net positive, as should be obvious.

On to some specific questions raised ...

(0) >>>[qume] The captain makes the same call on every flight. The plane and passengers are her responsibility regardless of the situation. Edit - also the call is made continuously. They can back out any time.

Response: Only half true: the pilot-in-command (PIC) along with the aircraft dispatcher share responsibility for the "initiation, operation and termination of the flight." (Yes, I think the regs use 'termination'; that always made me wince.)

So, it's a quorum of two: if either one chooses to terminate (or 'not initiate') a given flight, it cannot be operated. That doesn't mean that a dispatcher who disagrees won't spend some effort presenting evidence for his position (e.g., ten-minute phone calls), but at the end of the day of those two don't agree, the flight cannot operate.

(1) >>> [phkahler] They may or may not have volunteered for the flight, but they do get the final decision to go in or turn back once the airline OKs it.

Response: This statement begs the question: who is "the airline?" The relevant US regulations (CFR 14 Part 121) refer throughout to this entity as the 'certificate holder' -- because an air carrier holds an operator's license -- a business license, of sorts -- granted by 'the administrator,' the regulatory term for the FAA. I'd gamble that since the FAA descended from the CAA that the policy authors thought it wise to anonymise the parties wherever possible in the event of future language changes. Smart move.

So for any given flight, "the airline" would be the dispatcher, who by proxy, exercises the right of 'the certificate holder' to "operate a particular flight over a specific route under specific conditions" (going from memory, mind you).

This authorization is formally granted by way of a legal document prepared by 'the certificate holder' (read: dispatcher) known as the 'dispatch release,' which includes a minimum set of specific information (flight plan, equipment type and number, flight crew, fuel min/max/burn, alternate airports, and so forth) but typically have an abundance of supplementary information to better brief the flight crew of the expected conditions and details of alternatives that are likely to be available if the proposed plan cannot be followed.

Bonus fact: If you ever were waiting after boarding and the crew came over the PA to say they are "waiting on paperwork," most of the time it is a bag/weight count, but some times it's the dispatch release. If you know your flight is going across, or into, some crappy weather, the chances of the latter are greater than average.

(2) >>>[passivepinetree] Does anybody who works in the industry have any idea of what the risk management is like for these types of events?

Response: The airline operations hundreds of flights a day; all have some risk, and all decisions must be made in real-time. In cases of long-running events such as a hurricane, there is likely to be some general tone taken by the carrier at the highest operational levels (chief pilots, chief dispatchers, VP of Operations, etc.). For my carrier, these strategic positions would be discussed in the morning meeting, which was a recurring conference call between all those parties and department supervisors -- kind of like a stand-up, except we were all sitting around a conference table.

Aside from that, as the day wears on the specific handling of a given route, weather event, etc., is handled in real-time by the assigned dispatcher and support team (meteorologists, mechanics, etc.)

Of note: some larger carriers maintain a 'Trouble Desk' staffed by dispatchers who are assigned a lighter workload than the regular line folks. This is a great system (one that my carrier didn't have) because, let me tell you, just one fubar flight can monopolize all your capability and time for quite a while. If/when one of those flights pops off the queue it can wreck your throughput for the remainder of the shift. For my money, the trouble desk is an excellent mitigation tactic capable of keeping the workload in the dispatch office sharded appropriately.

(3) >>>[joemi] Does anyone know more about this type of pre-hurricane flight? Is that a common thing airlines do, to try to squeeze one last flight in? Are there rushes before other types of bad weather?

Response: I only had a handful of duty experiences with hurricane landings that were in our region of operation, but I do have a wealth of experience with other severe weather systems here in the US -- aka, tornado season.

There were many occasions when a strong cold front would be bearing down on cities we served, with solid lines of thunderstorms sweeping through the region. The kinds of weather that serve up severe or extreme turbulence, large hail, and tornadic activity. And there aren't any "holes" to "slip through," either.

Frequently, it would come down to trying to get one more flight in and out of a city. (The pressures of 'completion factor' at an airline are a whole discussion in itself.) In these cases, I'd be measuring the relative velocity of the line versus the distance to the airfield, estimating the time of impact, so to speak, and cross-referencing that against my computed time en route and considering the turn-time at the station, etc., etc.

Assuming you judge that it can be operated safely, and you can provide a suitable alternate plan (and "turn back to base" is certainly a common choice) you have to get on the phone (or radio) and brief the PIC on some or all of the details (all of the details are in the dispatch, but people like to hear a human voice when facing stressful situations; think 911 operators), and if they concur (or accede, in some cases) then, from (1), by the necessary joint agreement, the flight is initiated.

And as you might expect, sometimes the flight got in and out, and sometimes it diverted or came back to base. In either case, occasionally the crew might call or radio back in with reports on the conditions (or vociferous complaints about the ride quality -- hey, it happens).

So then my unqualified answer to this question from joemi is "Yes."

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Finally I'd like to call out the commenters who made mention of the ground (and other station) crew and their exposure to risk in these "irregular operations"; I'd say they exhibited a measure of aplomb no less than the flight crew, and those employees are too often overlooked as essential parts of the carrier's operations; both day-to-day and in extreme cases such as a hurricane landfall.

HTH, /Acey

I guess a mix of heroes and craziness.

Congratulation to everyone involved and thankfully everything went alright.

An evac flight could even go full on quick load. No checked bags, one carry-on max, forget assigned seats and just fill the plane from back to front as fast as possible to get out of dodge.