It's a bird, it's a plane, its a contrail

  • Charles Kulander

 

When we moved to the Colorado Plateau 20 years ago, I thought I'd be trading an ocean coast for a pristine Western sky.

Instead, I was greeted by a nonstop parade of thundering jets roaring along one of the main air-transportation routes in the country, linking the East Coast to San Francisco. Congratulations, I told myself: We move to the end of a dirt road only to find ourselves living under a freeway overpass.

For me, jet noise ranks right up there with overhead power lines and billboards, so I was all the more astounded when my mother-in-law, craning her head upwards, exclaimed how lucky we were to have those jets over our heads.

"They're so beautiful, she said, clasping her hands in delight. "Streaking through the sky to God knows where. It's like a dream!"

"Yagottabekiddin'me," I said, slapping my forehead, my standard reaction to many mother-in-law comments.

The constant jet traffic had been grating on my nerves for years. I too easily imagined stressed-out flight attendants ramming food carts into the knees of their comatose passengers. Then there were the contrails the planes leave behind, airbrushing the sky like corporate-sponsored graffiti.

On days when contrails tic-tac-toe the sky, I empathize with my paranoid friends who see them as "chemtrails," toxic chemicals the government is releasing in a conspiratorial effort to sterilize the masses ... or vaccinate us ... or bio-engineer the weather ... or some other evil purpose.

The truth is more mundane: Commercial flights follow narrow routes that crisscross the West. About the only areas not within these 8-mile-wide air corridors are marked on the map by blue boxes - the no-fly zones used by the military. If you want contrail-free skies, the best bet is Area 51 in Nevada, or the White Sands Missile Range in New Mexico.

On the other hand, high-altitude jet contrails can be useful. I once knew two Hawaiians who regularly sailed sailboats from California to Waikiki. They'd show up at the marina without a sextant or charts. We all thought they relied on Ancient Polynesian star knowledge, until one night they spilled the beans: "Hey brah, we just follow d' jet trails."

I've found contrails to be helpful in other ways. First, they usually make great weather indicators. Contrails form when heated hydrogen, a by-product of burned jet fuel, mixes with atmospheric oxygen to make water. If the temperature is cold enough, the water immediately freezes into ice crystals. The brighter and longer the contrail, the colder it is up in the jet stream. And if you keep your eye on the contrail's drift, you'll also get an idea of which way the jet stream is blowing.

Not only do contrails illustrate weather conditions, they also are fiscally responsible, unlike the cirrus and cumulus that float by without a care in the world. Jet contrails are Clouds That Pay Taxes. In most states, airlines pay a use tax that goes into a general statewide fund, which often gets distributed to rural counties.

Lately, I've been imitating bird watchers and spying on jets with binoculars, and now, it's easier for me to identify different jets than it is to tell a king bird from a flycatcher. They reveal themselves by the pattern of their contrails -- the pinched stream of a DC-9, the triple wake of a 727, the parallel ski track of the 737, the grand four-furrow sweep of a 747.

So I have slowly and grudgingly adapted to the jets' presence, a constant reminder of the outside world. In the aftermath of 9/11, those few days when air traffic ceased and the world held its breath, I almost found myself wishing to see a few contrails chalk across the silent skies.

These days, whenever I find myself afflicted with "valley vision," the shortsightedness caused by the cloistered valley where I live, I just look up and watch the jets flying through at 28,000 feet. It always adds perspective to my day. And while I still have a hard time agreeing with my mother-in-law about the beauty of the jets passing overhead, I find myself keeping an eye out for them, especially at sunset when the sun glints off their aluminum skin, and the ice-crystal trail they leave behind looks like the wake of a ship at sea.

Charles Kulander is a contributor to Writers on the Range, a service of High Country News (hcn.org). He is a writer in Moab, Utah.

Rusty Austin
Rusty Austin Subscriber
May 27, 2011 06:59 PM
Funny, I live under the downwind leg of LAX. I have become adept at spotting both the type of jet, and the carrier. Also, depending on how the wind is blowing, I can ID a jet from the noise alone (Airbus A300s are the noisiest by the way). So I live in the middle of one of the densest cities in the world, and Charles lives in the middle of nowhere, yet we have a common experience every day. It's a small world isn't it.
Deb Dedon
Deb Dedon Subscriber
May 31, 2011 07:11 PM
I live under the flight path of Davis-Monthan AFB, not that the present flight path was operative when I bought my house. Just after I arrived in Tucson, a DMAFB jet crash landed in the middle of a side street five blocks away, burning to death two sisters trapped in their car. The pilot ejected safely and the fireball stopped short of the U of A campus. For years thereafter, no military jets rattled windows at the U of A or its ring of neighborhoods. When enough time had passed, the powers that be believed we had forgotten those two women reduced to ashes and flights resumed.

I know this essay is about the beauty of contrails dispersing on high altitude winds, but I couldn't help pointing to their source. Some see freedom and beauty in jets and their frozen exhaust, but I still see a funeral pyre.
Peter Smidinger
Peter Smidinger Subscriber
Jun 09, 2011 02:27 PM
Hydrogen is burned first in fuel combustion, before and during the carbon burning. The jet exhaust is already water vapor before it leaves the engine nacelle, and it cools almost instantly below the dew point to make visible droplets (cloud). Instantly because the drop in pressure from the combustion chamber to the ambient air outside at high altitude makes for a bunch of adiabatic cooling.
The solar reflecting contrails probably slightly and temporarily offset the CO2 warming, but a real inconvenient consequence for astronomers is the decrease in acuity of telescope and instrument vision at places like Kitt Peak Observatory.
Robb Cadwell
Robb Cadwell Subscriber
Jun 09, 2011 09:14 PM
One year back in the early 90s I lived up in NW Yunnan not too far from Tibet and Burma. After a few days of seeing not one aircraft of any sort I started to watch for one. Never did see a one except one helicopter that landed down by lake Ehrhai one day. I thought to myself how many places are there in the world that aren't flown over by some sort of commercial jet or at least the odd military aircraft. I wonder.