Contrails

On a perfectly clear afternoon during the spring and summer, I usually see several bright, white streaks crisscrossing the sky—more often in the late afternoon. These lines are called contrails, the exhaust from commercial jet airliners flying at 30,000 feet or more. Contrail is a condensation of the term “condensation trail” (pun intended.)

If a plane is nearly overhead, I often see the reflection of the sun off the silver-colored wings and fuselage, even if the plane is more than five miles above me.

Courtesy: fastcodesign.com

Contrails are formed when the super-heated exhaust from a jet engine hits the extremely cold air (minus-35 degrees F) and forms a collection of frozen particles that form a white trail behind the airplane. Under certain conditions, contrails can also be formed by the wings or tail of an aircraft. Depending on the temperature, humidity and wind currents, this line may be several miles long or dissipate very quickly.

I find these trails fascinating to observe, to see how long they last and I wonder what the destination of the flight could be based on the alignment of the flight path revealed by the contrail.

Contrails and Jets

Transcontinental commercial jet air service dates to 1958 when Boeing introduced the 707. This plane could carry over 150 passengers from New York to Los Angeles in a little over five hours. Now commercial jet flights are routine for many Americans. And, while everyone complains about ticket prices, I think it’s a pretty good bargain to be able to fly from Northeast Ohio to the West Coast and back for about $400 or less.

International jet flights are making the world smaller, allowing Americans to get to Western Europe in six or seven hours from the East Coast. My son spent one college semester in Thailand and he flew from Chicago to Bangkok (with a stop in Tokyo) in about 19 hours—11 time zones and nearly 9,000 miles. That’s pretty amazing.

I remember in 1958 when the Brooklyn Dodgers moved to LA and the New York Giants moved to San Francisco. The emergence of non-stop, reasonably fast air transportation made this more palatable to the owners of major league baseball teams, who were concerned about the length of trips for visiting teams and the three-hour time zone difference.

The economic and social impact of relatively cheap world travel has a profound effect on all of us. Along with communication satellites and the Internet, the world really is getting smaller in a figurative sense and I think that is a good thing.

Contrails,"Chemtrails" and the Environment

But, whenever a new technology takes hold, there are usually naysayers. Some environmentalists complain that commercial jets contribute significantly to climate change.  It is true that commercial jet exhaust contains very small amounts of particulate matter, the material is widely dispersed and doesn’t make it to the ground six miles below.  

The exhaust is super hot when it leaves the rear of the engine, but it is cooled rapidly and contrails are formed. For three days immediately after the 911 attacks, the Federal Government grounded all commercial air traffic in the country. Some enterprising scientists took measurements of air temperature during this time and then again after commercial flights resumed.  There was a very slight increase once the flights resumed, but most of these scientists felt it was insignificant.

Also attacking jet air transportation are the conspiracy theorists who have renamed contrails as “chemtrails.” They maintain that the exhaust of commercial airliners contains chemical and/or biological agents being spread over an unsuspecting populace for sinister purposes. These rumors took root in the mid-90s when the U.S. Air Force Air College drafted a strategy paper that discussed how jet aircraft could be used to create some climate change by the year 2025. Most experts agree that releasing any other substances from that altitude would be ineffective because the material would dissipate and not reach the ground.

So, later this spring and summer, when I sit on my deck with a cold drink and gaze at the “blue suburban sky” (Thank you, Paul McCartney!), I’ll notice the contrails. I’ll wonder about the origin and destination of each flight.  Are the flights heading to the northeast taking the polar route to Europe? Are the westerly flights heading for LA or San Francisco? And I’ll still marvel that 15O or more people could be going thousands of miles to visit family, close a business deal or visit a faraway land and experience its culture. And they will get there in a few hours.

Depending where the plane is heading, I’d like to be going with them