The Liberty Gazette
February 7, 2017
Ely Air LinesBy Mike Ely and Linda Street-Ely
Linda: Randall Munroe’s book, “What If?: Serious Scientific Answers to Absurd Hypothetical Questions”, was spurred by the success of his wildly nerdy-popular web-comic, xkcd, where stick figures compliment text on complex subjects.
Through xkcd Randall entertained questions submitted by fans and answered them with remarkably brainy, humorous explanations as only a NASA physicist could do. That reminds me of a bumper sticker: “NASA: It’s not rocket science. Oh, wait, yes it is.”
Mike: And that reminds me Chris, a brilliant young man. His first job out of college paid well but didn’t hold anywhere near the esteem that NASA would on his curriculum vitae. When the organization offered him a job he quickly accepted and turned in his two-week notice to his then-present employer. His co-workers were impressed and assumed he would be making a pile of money, but Chris set them straight. “No, I won’t be making that much. It’s actually going to be a reduction in salary.” This baffled those he was leaving behind. After all, how could less pay be a step up?
“You don’t understand,” Chris answered earnestly, without hiding his frustration that they didn’t get it. “It’s NASA!”
Linda: Back to Randall Munroe. A young techie fan named Glen submitted this question: “What would happen if you tried to fly a normal Earth airplane above different Solar System bodies?”
Randall formulated his answer around the most popular general aviation airplane, a Cessna 172, “Skyhawk”.
Besides obvious concerns such as Jupiter’s extra-strength gravity, and excessive temperatures in either direction around all planets other than Earth, if we only consider the essential component of lift, the lack thereof grounds the idea. There aren’t enough air molecules out there in that thin air to create the amount of lift needed. Lift is the thing that makes airplanes fly. They have to go fast enough through air molecules to create high pressure under the wing, low pressure over the wing. The airplane in space would have to fly so fast to get through the same number of air molecules needed to “hold it up” that the speed itself would probably kill the pilot, and if not, for sure the landing would.
Mike: There is, however, a planet Munroe says has a better atmosphere for flying than Earth’s: the planet, Titan. According to his answer to Glen, the air is so thick and the gravity so light that if it weren’t for the sub-freezing temperatures even we as humans could strap on wings and fly with just our own strength.
Remember the story of Icarus? In Greek mythology, Icarus’s father, Daedalus constructs wings out of feathers and wax so they can escape from Crete. Daedalus warns his son not to fly too low where that the moisture of the sea could clog the wings, nor too high, where the blistering heat from the sun would melt the wax. Of course, Icarus ignored his dad and flew too close to the sun. The wax melted and he fell into the sea.
Linda: Munroe concluded with his signature wit and brilliance, “I've never seen the Icarus story as a lesson about the limitations of humans. I see it as a lesson about the limitations of wax as an adhesive. The cold of Titan is just an engineering problem. With the right refitting, and the right heat sources, a Cessna 172 could fly on Titan—and so could we.”
I think those first two sentences would look great on a motivational poster, don’t you?