Slashdot Mirror
Zapping Contrails With Microwave Emitters
An anonymous reader writes "Dissipation of contrails with a powerful microwave beam aligned behind aircraft engines is being touted as a possible solution to help address air transport's effects on the climate. 'The remote heating of condensation nuclei could be achieved by applying electromagnetic radiation, such as microwaves,' says Cranfield University's Frank Noppel. 'Depending on assumptions made, calculation shows that the power required for such a device could be as little as 0.1% of the engine power.'"
a possible solution to help address air transport's effects on the climate........ so the "a possible solution" to those little white trails behind jets that usually dissipate quite quickly is to shoot a powerful microwave beam in the sky. What could possibly go wrong?
I'm an American. I love this country and the freedoms that we used to have.
calculation shows that the power required for such a device could be as little as 0.1% of the engine power.
A 747 uses four RB211 engines (or the Pratt & Witney equivalent) each of which puts out 30 megawatts of power. So this microwave contrail zapper is going to be using 120 kilowatts of power? That's 60-80 kitchen microwaves running simultaneously. That's more power than many radio stations use to transmit. I can't help thinking this will cause more problems than it solves. How is it going to affect radar, TV, cell phones, etc? How is it going to affect other planes on the same flight path? How is it going to affect the moisture already in the air? What's going to happen when one of these aircraft come in for a landing and forgets to turn off their contrail zapper?
It's probably money a lot better spent trying to build cleaner burning engines in the first place.
When our name is on the back of your car, we're behind you all the way!
Jet contrails apparently serve to cool the Earth during the day, as they reflect solar radiation, while at night they serve to warm the Earth, by trapping heat. So for maximum effect, you'd want to only dissipate the contrails created during nighttime flights. This would include not just "red-eye" flights, but air cargo operations like FexEx. Measurements taken during the grounding of all commercial flights following 9/11 indicate that there was a two degree increase in the range of day/night temperatures, so elimination of just the nighttime contrails could lower temperatures by a degree or so.
http://archives.cnn.com/2002/TECH/science/08/07/contrails.climate/index.html
Nothing for 6-digit uids?
My first expectation was something for bomber jets to make them less visible. I'd be surprised if it doesnt get ported over.
Correllation != Causation
however: Correlation != Causation unlikely/impossible
True confidence comes not from realising you are as good as your peers, but that your peers are as bad as you are.
I seem to recall reading that one 747 during takeoff creates more pollution than a Toyota Prius will in its entire serviceable lifetime.
Let's not compare apples to oranges.
A 747 can carry up to 660 passengers in a single-class configuration. That's 132 priuses full of people.
To drive from NYC to LA is 2,791 miles. Repeating that drive 132 times will put 368,412 miles on your odometer. Although I'm sure the Prius is a very reliable car, it's unreasonable to expect any vehicle to last that long without a major overhaul.