TSGS Cruiser Blog

Friday, May 25, 2012

"What is a Contrail?"

A few days ago, I was outside with an associate who knew I had been in the U.S. Air Force.  A jet was soaring high above us.  I was asked to identify the jet.  Well, all you could see was a white dot with a very long white trail that extended the full length of the sky.  I told my friend that even if I knew something about jets, at this distance, I would not be able to make even a guess.  I further stated that I really did not know much about aircraft.  "What?" he retorted, "you were in the Air Force and do not know anything about jets?"  He was amazed at my seemingly impossible lack of knowledge about things he thought was second nature for anyone in the Air Force.  I explained that I was in Air Weather Service and was trained in high altitude weather data calculations that was used in flight planning and in predicting or forecasting the weather.  I could tell that my friend was impressed that I was connected to weather forecasting.  He immediately asked me what kind of clouds were in the sky.  I told him that I thought they were cumulus clouds, but that they might be stratus clouds... I really was not sure.  Now, I detected that he thought I was not very smart or I was not a very good serviceman.  So, I quickly told him that the long white trail from the jet was called a "contrail" (short for condensation trail) caused by the hot jet engine exhaust hitting the cool atmosphere.  I told him that I was never a weather observer, but, rather, a Rawinsonde Operator who charted data submitted from a transmitter attached to a large helium/hydrogen filled balloon tracked by radar.  He thought that sounded complicated, but important.  It did take special training and was important for flight plans and forecasting weather pattern changes.  Then he said, "so, that long white trail is called a "contrail" created by the warm exhaust hitting the cooler atmosphere!"  I smiled and said "that is correct!"

My friend is like all of us in that we assume certain facts to exist just by association.  I was in the Air Force and he assumed I knew all about jets.  Then, he assumed that my knowledge in Air Weather was that of being a weather observer.  There was no doubt that he was glad I at least knew something interesting about that white trail in the sky and that it is called a "contrail."

This little story might help us when we research, especially genealogical research.  We must be very careful to not just assume certain conclusions based on our perceived absolute truths or experience.  It is easy to assume that Thomas Goldman, Sr. and Thomas Goldman, Jr. of the same geographical area to be father and son... but the true facts are that the use of "senior" and "junior" was a way to tell them apart... one was the older Goldman.  Not only might they not be father and son, they might not even be related!  Or have you heard this one... they are not related to our family because we spell the name "Goldman" not "Gouldmann!"  Of course we all should know that is not always true!!!  Names with variations in spelling are often the result of how others decided how the name should be spelled.

I hope my little "contrail" story will remind you to avoid falling into the trap of assuming things are true when other possibilities may exist.  - JGWest

No comments: