De Icing question
 

Delta 8894 in MSY heard pilot request de icing temperature is 50 degrees just curious.

MSY needs up their game and switch to solar deicing like we use at MCO. 😁

But to help answer the question the wings are susceptible to ice at higher temperatures due to the fuel tanks.

When you say 'solar' de-icing, do you mean waiting for the sun to come up and melt the frost?

I’ve been a flight that did that. Truck was broken, we turned into the sun and sat for a half hour. Pilot came back into the cabin and looked at the wings before deciding to take off.

Yes, that's exactly the kind of de-icing system used across Florida.

In YVR I've seen lots of deicing around 50F. The record I've seen is 52F.
At those high temperature, it was almost always a CX B777-300 or an ACB777-200LR.

When an airplane flies a long flight the fuel in the tanks becomes very cold. When it lands, that cold fuel keeps the wing's metal skin very cold for quite some time. If the air on the ground is (relatively) warm and humid, condensation will form on the wing just as it forms on a cold glass of ice tea on a humid day. If the fuel was cold enough, and the wing's skin is below freezing, that condensation will be in the form of frost and will have to be removed before the next flight. The DC9 series (MD80/MD90/MD95/B717) tended to be particularly susceptible to this form of icing.

According to flightradar24, DL 8894 was an A333 departing MSY at about 3:10 AM. Probably taking Clemson home after the Sugar Bowl.

Solar de-icing tends to be broken at 3:10 AM at MSY.

And the OP is a Buckeye fan making sure they got home safely. LOL

"Susceptible" mostly because the ice can find an engine behind the wing to shed into for the case of cold-soaked fuel forming ice on the top of the wing (on top of a fuel tank under the wing skin) even in the solar warmed air.
That situation, rare as it was, could be aggravated when the operator tankered fuel (more than he needed for a single flight ) to shortened his turnaround time at a en-route airport. However for most aircraft the biggest concern is temperature closer to freezing with visible precip causing ice on the front of a wing or in an inlet of an engine during taxi out.

Yup, most Florida airports' deicing strategy is to just park it in the sun for a little while. :D

PHX has the same de-icing system, which sometimes means an hour (or so) delay on early-morning flights in winter.

Years and years ago, I was flying out of MSY on the day after Christmas. Cold rain fell overnight with the temps around freezing and continued all morning. MSY ran out of deicing fluid completely after the first few flights of the morning. I don't think anything flew out that day, until they could tanker in more deicing fluid from somewhere. I ended up getting rebooked by DL for the next day - instead of MSY-DFW-ONT I ended up flying MSY-DFW-BUR.

Perhaps a stupid question: I understand planes need to be deiced prior to takeoff under various circumstances. But aren't the same conditions around when planes are landing? I know planes can't be deiced inbound but aren't the same freezing conditions effecting the aircraft yet they land without the deicing fluid on them.

Another question I've wondered about: Every time I see a plane get deiced prior to takeoff including the planes I've been on, it seems the plane sits at the deicing station about 10 minutes after the deicing fluid is applied before it heads to the runway for takeoff. Seems like it would make more sense to take off right away rather than wait but is there some kind of "curing time" involved?
Thanks!

For your first question, when the aircraft is in the air, it's never traveling less than ~100mph. If you've ever driven a car, you'll know that when you're driving, even in heavy rain, if you're in a sedan/car your back window really doesn't get rain on it and stays dry, it's only when you stop that the window starts to get wet. The same principle applies to icing on an aircraft wing. As the aircraft flies through precipitation, it tends to freeze on the leading edge of the wing, which on most aircraft is heated or equipped with some kind of de-ice or anti-ice system. In contrast, when the aircraft is stationary on the ground, precipitation or in this case condensation forms and freezes all over the wing's surface, not just the leading edge. These other surfaces are not equipped with systems to prevent icing.

As for your second questions, I'm not totally sure. I think in general that will just be a result of the restart process and getting into a departure queue.