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Airplane Coatings Help Recoup Fuel Efficiency Lost To Bug Splatter
MTorrice writes: When bugs hit the wings of oncoming airplanes, they create a problem. Their blood, called hemolymph, sticks to an airplane's wings, disrupting the smooth airflow over them and reducing the aircraft's fuel efficiency. To fight the problem, NASA is working on developing a coating that could help aircraft repel bug remains during flight. After experimenting with almost 200 different formulations, researchers recently flight-tested a few promising candidates. Results showed that they could reduce the amount of stuck bug guts on the wings by up to 40%. With further optimization, NASA says such coatings could allow planes to use 5% less fuel.
First of all - where do I pick up one of these guns:
"To test these materials in the lab, researchers developed a pneumatic launcher to fire living bugs at a sample coating. They first used crickets as ammunition, but a physicist colleague urged them to switch to fruit flies, which would be more representative of what planes hit during takeoff and landing."
Second - I hope they develop a clear coating as I would like it on my motorcycle visor.
It's not weight, it's maintaining laminar flow. It only takes very small objects to turbulate the boundary layer, increasing drag considerably.
http://www.dianasailplanes.com...
Surely, you're utterly wrong. One takeoff can easily put enough bugs on the leading edge to destroy laminar flow. Heavy bug loads on the leading edge can easily increase drag by 30% over a clean wing. Glider pilots use mechanical wipers to remove the bugs in flight. Waviness of more than .005 inch is needed to maintain laminar flow. Once the flow becomes turbulent, drag rises considerably. Just washing the wings on the ground won't help.
Bug guts are sticky. They do not simply hose off. You need to actually scrub them off, and if you're doing that, you need skilled labor because there are lots of sensitive things that stick out of aircraft.
More than one aircraft has been lost because someone missed removing some tape covering some hole or other that was applied in order to wash the aircraft.
And there's a lot of surface to scrub, too.
Even little bug smashers like Cessnas take a good while to clean off (and flying through a bog meant you often flew through a crowd of mosquitos, so the leading edge was covered in lots of little red spots).
American corporations will instead do the following.
Get a government grant for the coatings, claim the actual full purchase price at full retail as the cost and pass that cost to ticket buyers.
Use the 5% fuel savings as a ,"we are saving the planet.... see? SEE?" advertising campaign.
Also add the costs of the advertising to the ticket prices.
Profits go up an additional 75%, claim they need more government subsidies.
Do not look at laser with remaining good eye.
Under every summary, there's a small puzzle of colored blocks. Looks like it says "bird fucking", but I don't get it.
Rain-X! Lots and lots of Rain-X!!!
Life is not for the lazy.
The most sensitive part of a modern aircraft wing is just aft of the leading edge where the flow makes the transition from subsonic to transonic. Having even 'frosting' in this area can destroy all lift from a wing so they are liberally sprayed with gelatinous treatments that are specially formulated to melt any ice that forms from rain or snow while the aircraft is static, yet become sufficiently diluted during the take off to be washed of the wing for flight.
Once airborne, the problem becomes one of thermal balance and heat is supplied to the wing leading edges using engine bleed air.
The bugs don't affect icing and so far, no coating has been found that cna get rid of ice under all conditions mandated by the FAA.
"Our opponent is an alien starship packed with atomic bombs," I said. "we have a protractor"
Have gnu, will travel.
Rain-X! Lots and lots of Rain-X!!!
My dad used to use Rain-X on his propeller to keep the bugs from sticking. It actually worked pretty well but had to be reapplied fairly often. I think they're going for something a little more permanent here.
-- Remember, we're not happy until you're not happy. -- Local FAA Inspector --
I'm from Buenos Aires, and I say kill 'em all!
There is some loss of laminar flow, but 5% seems wildly optimistic for eliminating bugs under any normal sort of operation. I only fly piston planes so maybe someone flying jets can comment, but 5% is enough to affect your fuel reserve calculations and I've never heard of a "bug" correction.