Remember when a volcano in Iceland erupted back in 2010, sending giant plumes of ash into the sky? It drifted southeast toward Europe, prompting authorities to close most of Europe's airspace for nearly a week. Millions of travelers in Europe and beyond were stuck on the ground.
I was among the many stranded in London because of the ash cloud, and I can tell you that the mass closures did not go down well with travellers.
"It demonstrated our reliance on flying and on what, in extreme circumstances, can go wrong," said Tom Hall, the London editor for Lonely Planet. "It felt for some time that there wasn't really a plan, and it exposed the Achilles heel somewhat of the idea of just getting on a plane and flying from one place to another."
The airlines lost an estimated 200 million dollars a day, and there were knock-on effects. Kenya's economy suffered because it couldn't send its fresh flowers to markets in Europe.
European officials came under fire for rushing to shut down so much airspace, based on the fear that the ash might bring down a plane.
Fred Prata could only watch as "better safe than sorry" became the European catch-phrase.
"The authorities didn't have enough information, and they weren't able to manage the situation," said Prata. "So they did what any regulator would do. They did these blanket groundings, which weren't really justified in retrospect."
Prata's a senior scientist at the Norwegian Institute for Air Research, and he's a world authority on volcanic ash clouds.
Prata himself was stuck in Los Angeles at a conference because of the ash-related shutdowns in April 2010.
Ian Davies, an engineer for the low-cost British carrier EasyJet, remembers calling Prata up around that time, asking him to come talk about what they could do in the future.
"He came, and we decided there was enough there we could collaborate on, to develop a detector such that if we had another disruption, we could minimize the disruption caused to our passengers," Davies said.
Prata was the right guy to call. He's been working for the past 20 years on something that he now calls the Airborne Volcanic Object Infrared Detector, or AVOID.
The idea involves mounting two infrared cameras somewhere on a plane. The cameras snap pictures – about 25 images per second – as the plane goes along.
Because ash looks different under infrared than water droplets or ice, it's not hard to distinguish it.
Computer systems can take the data and quickly determine the "ash dosage" a plane is likely to get.
The trick, according to Prata, is making the data useful to pilots when they're in the air.
"I'm a scientist and I can interpret them, but if you show that to a pilot who is busy with many other things, it's just simply not sensible," Prata said. "So, we're looking at ways of, I won't say 'dumbing it down,' but making it more useful. If we can present it something like he's used to seeing already, like a radar image, then the learning curve is much lower and the acceptance is much higher."
Prata said the AVOID system is not designed to replace satellite imaging for ash clouds. It would just provide another stream of data for forecasters and controllers.
He added that there's no need for every plane to be outfitted with the infrared cameras. Those already equipped could feed the information back to the ground.
And the data could help authorities make better decisions about when and where other planes should fly in the event of an eruption.
Last month, Prata tested the system on a small plane above Italy's Mount Etna. He worked with Konradin Weber, a physics professor at the University of Duesseldorf in Germany.
Weber said the advantage of the AVOID system is that it can detect dangerous ash levels miles before a plane flies through them.
"You get the warning at an early point, so you're able to fly around the plumes," Weber said.
Next up, the scientists said, is to work with Airbus and EasyJet on testing the system on passenger aircraft.
Fred Prata estimates that each system would cost around 30,000 dollars to install.
That's a small price compared to the billions lost during the Iceland ash cloud incident nearly two years ago.