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Delta Goes Big, Then Goes Home

flightradar24.com

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Re: Delta Goes Big, Then Goes Home

#61

Post by jandrese »

The only disappointment for me is that they flew a relatively modest 737 down there. If you're going to make a heroic flight like this do it in an A380 or a 747 and load up as many people as you can to get them out of dodge. I guess shuffling a big plane like that at the last minute is probably not feasible since they have their own routes to service.

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.

Re: Delta Goes Big, Then Goes Home

#63

Post by 21 »

jimktrains2 wrote: post #54
stepik777 wrote: post #8

Why can't they use some sane colormaps instead of this garbage?

You mean the meteorological charts? It is a sane color map? What would you like to see changed or had trouble reading?

I think he is talking about the actual false colors being used. I also thought the same thing.

The picture seems to use the "Jet" Matlab colormap, which is pretty bad by many accounts:

https://www.youtube.com/watch?v=xAoljeRJ3lU

https://matplotlib.org/users/colormaps.html

https://bids.github.io/colormap/

Re: Delta Goes Big, Then Goes Home

#64

Post by lisper »

lightbyte wrote: post #39
lisper wrote: post #30

Earlier quoted context omitted.

Hurricanes usually have embedded thunderstorms.

So does non-hurricane air. The hurricane by itself presents very little danger to a plane in the air.

> So does non-hurricane air

That depends on what you mean by "non-hurricane air." An embedded thunderstorm by definition has to be embedded in some other weather system. That other weather system doesn't have to be a hurricane, but so what? That doesn't change the fact that one of the many dangers of flying into a hurricane is the embedded thunderstorms it contains.

http://www.nhc.noaa.gov/prepare/hazards.php

"Hurricanes and tropical storms can also produce tornadoes. These tornadoes most often occur in thunderstorms embedded in rain bands well away from the center of the hurricane; however, they can also occur near the eyewall."

> The hurricane by itself presents very little danger to a plane in the air

That's a vacuous statement. Yes, if you remove all the dangerous parts of a hurricane, whatever remains is, by definition, not dangerous. And yes, it's true that strong winds by themselves are not dangerous. Commercial airliners regularly fly through the jet stream which is comparable to a hurricane in terms of wind speed. But that doesn't change the fact that hurricanes contain embedded thunderstorms, which can be very dangerous.

Re: Delta Goes Big, Then Goes Home

#65

Post by simplyluke »

During the cold war my grandfather flew bombers into the eyes of hurricanes to drop sonar beacons. I'm sure he'd get a kick out of this.

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.

Re: Delta Goes Big, Then Goes Home

#66

Post by bonkabonka »

DigitalJack wrote: post #59
ihsw2 wrote: post #26

Earlier quoted context omitted.

Hurricanes are relatively slow-moving, relatively predictable, and have relatively consistent wind speeds/directions. Obviously it would be quite bad to fly into a hurricane's rain bands (the weather outside of the "corridor" that the DL431 flight moved through). The real feat here is the real-time and reliable coordination between all interested parties -- as mentioned in the article, the meteorologists, dispatchers…

So you are saying thunderstorms contain more intense wind shear than a hurricane...I don't think I believe that.

I am reminded of this story I bumped into on Reddit some time ago. Granted it's a small plane but still:

https://www.reddit.com/r/flying/comments/10fcqm/whats_the_mo...

Re: Delta Goes Big, Then Goes Home

#67

Post by lisper »

Tuxer wrote: post #43
lisper wrote: post #28

Earlier quoted context omitted.

Private pilot with 20 yrs experience here... To say that a 737 would have "no problem" would be overly optimistic. A 737, like all commercial airliners, is pretty tough, but there are plenty of things in a hurricane that could bring one down. There's hail, up-and-downdrafts that far exceed the capability of the aircraft to overcome them, and turbulence severe enough to flip the plane inverted. The least likely event…

A hurricane isn't a thunderstorm, and has very limited vertical movement in its airflows. The hurricane hunter P3s do it.

> A hurricane isn't a thunderstorm,

That's true, but they can (and usually do) contain embedded thunderstorms.

> and has very limited vertical movement in its airflows.

Except for the embedded thunderstorms.

> The hurricane hunter P3s do it.

That's true, but they can do it because their destination is the eye of the storm. That allows you to do all your navigation relative to the storm.

Commercial airliners are trying to reach a destination on the ground, i.e. a target that is moving relative to the hurricane. Trying to navigate with this additional constraint is a whole different ballgame.

Re: Delta Goes Big, Then Goes Home

#68

Post by 21 »

DigitalJack wrote: post #55
throwaway613834 wrote: post #40

Earlier quoted context omitted.

What I'm saying is, you're saying this was a case of the airline trying to get out as many people as they could, without much regard for the risk and costs. But from what I see, they seemed to have optimized for the risk and the cost extremely well, to the point where it made perfect sense to do what they did, both business wise and humanitarian. Meaning those seem contradictory. (In no way am I playing down what the…

I'm sure they did their best to calculate it as precise as they can. Other airlines tried and failed. They had to turn back or were stuck on the island. So the realized risk is fuel and cost of a grounded plane.

They could have lost the plane according to the Wired article:

> Once the plane landed in San Juan, the alternative—leaving the plane on the tarmac or in a hangar—would probably have destroyed the airplane ... If the plane had gotten stuck, Delta probably could have gotten the humans out safely. But it almost certainly would have lost a plane.

Re: Delta Goes Big, Then Goes Home

#69

Post by jokamoto »

DigitalJack wrote: post #59
ihsw2 wrote: post #26

Earlier quoted context omitted.

Hurricanes are relatively slow-moving, relatively predictable, and have relatively consistent wind speeds/directions. Obviously it would be quite bad to fly into a hurricane's rain bands (the weather outside of the "corridor" that the DL431 flight moved through). The real feat here is the real-time and reliable coordination between all interested parties -- as mentioned in the article, the meteorologists, dispatchers…

So you are saying thunderstorms contain more intense wind shear than a hurricane...I don't think I believe that.

No, he's saying that the wind shear they had to contend with in the calmer corridor between rain bands was less intense than that found in a thunderstorm.

Re: Delta Goes Big, Then Goes Home

#70

Post by ceejayoz »

jandrese wrote: post #61

The only disappointment for me is that they flew a relatively modest 737 down there. If you're going to make a heroic flight like this do it in an A380 or a 747 and load up as many people as you can to get them out of dodge. I guess shuffling a big plane like that at the last minute is probably not feasible since they have their own routes to service. An evac flight could even go full on quick load. No checked bags,…

An A380 or 747 is significantly less nimble than a 737, and would take a lot longer to unload and load back up. The flight in question did a turnaround in 51 minutes, including taxing time, which is extremely quick.
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