Does Ice Really Fall From Aircraft Like This

www.bbc.co.uk...

"I came back at about 11 o'clock to find this huge crater in my garden. "My friend had called me. She works for my husband, from the house. She said she heard an almighty bang and felt the house shake and looked out the window and saw white fragments spread across the garden. "When I came back we realised it was ice."

My parents experienced this once in Scotland. A block of ice fell through a neighbours roof.

How common is this? Does it really fall from aircraft? Does anybody know for sure?

Don't lick it if its blue.

originally posted by: FredT
Don't lick it if its blue.

a reply to: Kester



"Aye" (I was in Scotland a couple weeks ago, beautiful area, beautiful. I even stayed in a castle 2 nights)
Definition of "Blue Ice"

www.mirror.co.uk...


And story #2 is a story about #2 hitting a Long Island couple

www.slate.com...

In the 90's I worked at a small airport. One day we had pretty good icing conditions and a King Air landed. While I was refueling it I noticed some ice on the propeller spinner. When I pulled it off I had a Viking hat about 3/8" (9mm) thick.

A katabatic wind, from the Greek word κατάβασις katabasis meaning "descending", is the technical name for a drainage wind, a wind that carries high density air from a higher elevation down a slope under the force of gravity.

Wikipedia.

That is when mountains are involved. The atmosphere can also stratify between layers.

As a plane ascends or descends through these layers ice can form. Usually, they don't grow to large sizes but it looks like they can!

Full disclosure, I was reading about Antarctica and how winds convert a solid snow flake back to water before it hits the ground (a reason why the back side of mountains can be drier than the other side). The first person to respond was like, "Duh! Any pilot can tell you this as you pass through layers of atmosphere..." which is the only reason I know about this! I looked up the stuff on Wikipedia and had it handy!

Don't keep it even if it looks like a comet.

I wonder if any of these ice chunks have ever hit anyone?

And if so, have any airlines have been sued?

a reply to: WakeUpBeer

They normally come offearly in the descent as they get into warmer air. Most of the time this happens on long haul flights when they stay in extremely cold air for a long time. It happens at other times, but the most common ones are from longer flights.

They've occasionally hit a house or car, and I think there was one that was claimed to have killed someone IIRC. The problem is that there are so many flights that it's almost impossible to narrow down exactly which aircraft it came from.

a reply to: Zaphod58

Pretty interesting. I'd think you'd hear more about them. Seems like they would be relatively common. Of course maybe it's just some mundane thing that I've never paid attention to. I guess there isn't any news (except local maybe) in it unless someone gets nailed.

What an annoying way to go that would be.

a reply to: WakeUpBeer

Ice doesn't normally build up in chunks that will fall off. Sometimes there's a leak in a vent mast and it slowly drips out and freezes, building into a block of ice around the end of the mast.

a reply to: FredT

When I was refueling planes in the Air Force I have seen a few planes with significant ice, and it's not like I got to them 5 minutes after they landed either.

Once there was so much water spilling off a wing I freaked out thinking it was a fuel leak. Nope, just a lot of melting ice.

a reply to: hounddoghowlie

Joe Dirt's meteor! That's exactly where my mind went. lol.

a reply to: face23785

That's how you can tell how much fuel is left and what tanks have fuel.

a reply to: Zaphod58

You mean how where there's fuel it won't get quite as cold and less ice will form? Or do I have that backwards?

a reply to: face23785

The tanks with ice or water have fuel in them. The more fuel in the tank, the thicker the ice gets. The tanks that don't have ice or water are empty.

If you notice on the -135, it's usually always the outboard wing tanks that are dry. They feed them into the inboard wing tanks as they burn fuel, and the inboards into the body.

a reply to: Zaphod58

I didn't know that. I was just taking a guess based on experience with our fuel storage systems. When it got cold out, our piping that was full of fuel usually wasn't quite as cold as other metal around it that wasn't full of fuel. I always figured the fuel was helping moderate the temperature, due to the FSII additive.

a reply to: face23785

The fuel in the pipes is more concentrated than in the fuel tanks. The bladders in the tanks also p play a role in it. In the case of the pipes, you're right, the fuel keeps it from freezing. Oddly though, the wing tanks are the exact opposite, even though it's the same fuel.

a reply to: Zaphod58

The way you explained it makes sense. Learned something new today.

a reply to: face23785

It's one reason I always walked under the wing near the outboard tanks. I got tired of getting dripped on while walking around looking things over.