If I tell someone that a situation will occur “when pigs fly,” then I am trying to say that the situation will never happen. There are events that will never come to pass, however I have seen pigs fly-just not the barnyard variety.
“Pig” is a term used to describe a device introduced into a pipeline and then propelled either by air, water or crude oil through the pipe. Some pigs can even inspect the pipe while passing through while others clean or remove all the contents of the pipeline. I recently used such a pig to clean out the underground pipe we used to water the cattle.
The pipe we used is 1 ½ inches in diameter and approximately 9000 feet long and can carry about 700 gallons at any time. It is buried only 20 inches below ground so I have to remove the water prior to freeze-up. It requires a large, industrial air compressor and my little buddy-a pig. The pig I use is made of foam, shaped liked a bullet and extremely adventurous. I stuff the pig into one end of the pipeline, attach the air compressor and let go with about 40 psi of impetus to move the pig the 1.7 miles to it’s exit.
The pig is shaped like a bullet and leaves the pipe much like it’s brethren leaves the barrel of a gun. The pig costs about $12 so I try to catch it as it explodes out the end of the pipe. I have yet to catch or confine the pig upon exit. I have tried tying a pail to the pipe, staked the pail down with a post and everything short of a Kevlar pig pen to keep this soft rocket earthbound but have always failed. I usually find the pail a few feet away with it’s handle still tied to the pipe.
I imagine the flight of the pig as a slow, tremendous build-up of pressure as it slowly advances through the line. The mass of compressed air shoves it along against the tremendous resistance of the interior wall of the pipe. As the pig exits its confines, followed by a column of propellant, it bursts through whatever defenses I have erected to constrain it and is at tree-top level in the first second or so. Much like the space shuttle, it makes a slow roll as it powers through the lower level atmosphere bound for lower orbit. The first few times I performed this act, fighter planes were scrambled and private aircraft redirected from the airspace directly above our little farm. I have learned now to file a flight plan for the little pig so as to cause less stir. I also sent a meat and cheese tray to NORAD as apology for causing them to scramble jets.
Upon re-entry, the pig must warm up a bit as it passes back into Earth’s atmosphere. I will never know as I’ve yet to meet the pig after it has completed its flight. I’m sure it reflects upon all it has seen during the trip; a dark subterranean crawl, a bright light as it exits the pipeline and then the various stages of atmosphere it samples both during ascension and upon descent from and to earth.
I wrote my column prior to this year’s “pig flight.” I will always remember 2011 as the fall in which the pig jammed against a pipe fixture and did not explode into the air. I was a little sad as I used pipe wrenches to remove my flightless little friend. I had finally captured him without even trying. Twelve dollars seemed cheap to fire my imagination as it allowed me to wonder of the exploits of the foam bullet pig. I think next year I will once again affix wings to whimsy and, fire up the air compressor and allow pigs to fly.