As you have probably heard, a piece of airplane wing, a flaperon, was found on Reunion Island and suspected to be part of the missing Malaysian flight.
How in the hell does a big honkin’ chunk of metal float, much less float hundreds of miles? I would think it floats like an anchor.
Um, cuz it’s hollow and air-tight?
From here:
You know, they haven’t made most ocean-going ships out of wood, with masts full of canvas sails, for many years now (since about the 1860’s). So somehow boat designers have figured out how to make “a big honkin’ chunk of metal float”.
It’s not purely a hunk of metal. Much of the skin of modern airplanes is made from composite panels with honeycomb core material that traps air and will float.
Not just metal. There are yearly concrete canoe races.
Do they expect to confirm that it’s part of the Malaysian flight plane?
I thought I heard on NPR last night that it was indeed confirmed. I’m too lazy to find or post a link tho.
A friend who’s an airline mechanic once told me that almost every part that goes into a modern airliner has a serial number on it. And they have to keep track of those for each plane, and when they replace a part, they update the records for that airframe.
So I expect that if it’s a sizable part, it will be traceable to tht plane.
The Malaysian Prime Minister says yes.
The French inspectors who are studying the matter say they want more study before they’ll say for sure.
There aren’t many (any) other planes it could have come from.
Boats are, you know, designed to float. Throw a car door in the water and see how long it floats.
I am not familiar with flaperon construction but see no reason why it would be deliberately constructed to be water-tight, although that property could be a side-effect of primary design goals.
I thought Boeing had NO other missing craft with this design.
When you hear hoof beats, think horses, not zebras.
But yes, it will be confirmed via prints on file.
Did you notice in the picture that a few guys were flipping it and lifting it? That should give you an estimate of its weight.
It just comes with the territory. One goal of aircraft design is to make everything as light as it can be while still performing its function. Therefore, most everything is hollow. If you look at photos of the flaperon you’ll see that it mostly consists of solid ribs and skin, which creates a row its full length of pretty big pockets of air. I suspect that water-tight sealing results, quite accidentally, from the piece being glued together in addition to being riveted–at 600 mph air is pummeling it awful hard, so you design in redundancies to keep the airplane together.
Weight alone isn’t relevant to floating. It’s the density (mass per volume) that matters.
I think that was implicit. There’s no way a few guys could lift an equal volume of salt water.
The flaperon is made almost entirely of carbon fiber composite. Basically very fancy fiberglass. And it’s hollow; it’s just a thin skin with some internal stiffeners, also made of the same fancy fiberglass. It’s very roughly 8" thick, 3 feet wide, 8 feet long, and weighs WAG 100 lbs. That’s plenty light enough to float.
It’s watertight because by design you don’t want rain and snow and deicing fluid to get inside there then sit and go through freeze-thaw cycles with every flight. And that particular piece was fortunate enough to not get a big gash punched into it during the crash. Similar parts that did get holed would have eventually filled with sea water & then sank months ago.
A Volkswagen will definitely float.
A Volkswagen will not float indefinitely.
It’s not even just about the overall density of the object as a solid. A large, flattened metal tube with open ends can be big and light overall, but will still sink. A big ball of wire mesh likewise.
Of course the object being discussed here appears to have a large, nearly-sealed cavity inside - it’s quite easy for something like this to end up floating even if it has a hole in it - because even if it partially fills with water, this will tip it into an orientation where the hole is either above or below the water line, so the exchange of air inside and water outside is stopped.
A glass bottle without a lid will usually fill partly with water, then float one way up or the other.
The internal configuration matters, too. Take a big oil tanker with a single internal tank. This isn’t a very stable configuration, because if it starts to tip, the oil flows with gravity, and doesn’t provide any counterstabilization force. The whole thing can roll over and release the oil (and let water in).
One solution is to add internal partitions, so that if it tips, the oil on one side of the ship can’t flow very far, and instead has to be lifted against gravity. The other side is pushed into the ocean and there’s a buoyant force. These two forces serve to restore the ship back to vertical and so you have a stable ship.