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Graphene-Based Coating Could Act As a Real-time De-Icer For Aircraft (rice.edu)
hypnosec writes: Researchers have developed a graphene-based coating they have proved effective at melting ice from a helicopter blade, paving the way for a real-time de-icer. The thin coating of graphene nanoribbons in epoxy has been developed by researchers at Rice University. In their tests, researchers show the coating is capable of melting centimeter-thick ice from a static helicopter rotor blade in a -4 degree Fahrenheit environment. A small voltage was applied to the coating that delivered electrothermal heat — called Joule heating — to the surface, which melted the ice.
Why does this pave the way to real-time de-icing? From the research, it appears to simply apply resistive heating techniques on the blade. Couldn't this already be done? Has nobody tried heading surfaces from inside before? What was the technical challenge?
As opposed to "batch", perhaps, if the submitter is old like me?
Do you really not know or are you being incorrectly sarcastic? De-icing is a horribly slow turn-based process now. Your plane gets in a slow line and moves up to the de-icing truck near where the taxiway meets the runway. Eventually, your plane gets the de-icing treatment and then because of the delay waiting for de-icing, the takeoff group is delaying because the next incoming bank has started arriving. By the time you take off, there's just as much snow built back up on the plane as when you left the gate.
This whole thing ought to be done more intelligently in regards to snow types. One time leaving Denver in a snowstorm, super-fine and dry Colorado powder was falling that blows away if the plane moves much at all but we sat through a long delay waiting for de-icing anyway. The captain was probably had some rule to follow that says sit through de-icing if snow is falling no matter what.
No, as in "in-flight" de-icing a helicopter's rotors ... you know, real time, under load, while in the air.
Typically you don't want a helicopter getting ice on the rotor, bad shit happens and it stops being able to fly.
Lost at C:>. Found at C.
The last time Science tried to come up with a new de-icer it didn't work out too well...
Just saying.
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Deicing doesn't deal with snow, or, well, not of the light fluffy kind anyway. It's mean to remove thick layers of solid ice that can form on surfaces and significantly affect aircraft performance. The reason for deicing when you see snow on the aircraft is because you can never be sure that there isn't at least part ice underneath it. That's why they deice, just to be sure. I'm sure you'll rather sit through an unnecessary deice 1000 times over than die once when it was really needed. Ice is no joke and people absolutely have died in aircraft because of it.
That having been said, the way it works is that they have types of deicing fluid, each of which is certified for a particular temperature and protection time. So something like up to 15 minutes of protection at -10C, 10 minutes of protection at -15C and 5 minutes of protection at -20C. The aircraft then has that allowable time window to line up and get airborne. In flight, it'll then either have to fully rely on its own anti-icing equipment, or exit the icing conditions (which usually happens fairly quickly).
The reason why we don't use an aircraft's own anti-icing equipment on the ground is because it isn't very extensive. It usually only protects critical components (typically wing leading edges, engine inlets/props and the main cockpit windshield panels plus some external sensors such as pitot-static tubes and AoA vanes) and may not be even be available for performance-critical phases of flight (such as takeoff), because it robs too much power. Adding more anti-icing equipment would add lots of weight and cost, not to mention power demand. *That's* why we thoroughly de-ice on the ground. Give the whole aircraft a good rinse, takeoff and quickly leave the icing conditions.
De-icing is a two-fold thing. The first part is to loosen any current ice buildup on the wings before takeoff so that the profile of the wing isn't affected. This is mostly accomplished by the pressure and heat of the de-icing fluid being sprayed about.
The second part is to reduce the formation of new ice buildup on the wing. Planes have waited too long in queues for takeoff and crashed because new ice formed since the last de-icing. The fluids have a sticky nature, like a syrup, that forms a layer of anti-freeze on the wing for a period of time. De-icing fluids are rated by the holdover time of the layer, which ranges from 5 minutes to 80 minutes depending on conditions and fluid type.
The airline industry has learned harsh lessons in the past about icing conditions and even if that dry Colorado powder can blow off when the plane moves, some might melt on contact with the surface of the wing and then freeze again on a different, colder, part of the wing. Be thankful for that rule that forces de-icing, otherwise airlines and pilots might take a chance they shouldn't.
Have a look at the accident reports for Scandinavian Airlines Flight 751, China Eastern Airlines Flight 5210, Air Florida Flight 90, Air Ontario Flight 1363 and USAir Flight 405. Decisions made by pilots, especially when under time constraints, within existing rules at the time can be really dumb sometimes and results in new rules.
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For fixed wing aircraft they can't take off hoping airflow will shake the ice off. Most likely they might still use high pressure water hose to shake the ice loose once it has been debonded from the wings. But plain water would freeze again. So it is back to glycol? May be heating the layer of ice right next to the wing will reduce the amount of antifreeze needed to de ice the wings.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact