Finding Your Altitude for Dummies

Analog altimeter

It never ceases to amaze our researchers just how... let's be nice and say "clueless"... some of the freelancers out there actually are. Some, we fear, are willfully ignorant; a category that seems to include many who "answer" questions at eHow.com. We think that may be why today's DotD candidate, one Jonra Springs, chose to address "How Do You Measure Altitude?"¹ in a rather clumsy (and not terribly accurate) fashion. Then again, it might simply be because Springs knew even less than the person asking the question.

Now for our money (which isn't much), the person asking that question isn't looking for instructions on using an altimeter; but that's what they got. Sadly, Jonra couldn't even get that right, rolling out such ludicrous claims as

"The typical starting point for altitude measurements is sea level, though some instruments use varying points to determine the level of the sea... Altitude is also shown on a Global Positioning System, but typically from a different sea level reference."

Those are some real head-scratchers: just WTF would "varying points to determine the level of the sea" mean? and where on earth did Springs get the notion that GPS uses a "different sea level reference"? It certainly doesn't say that in either of his references... probably because it's not true... Whatever the case, Springs reproduces, at length, some instructions for using barometric altimeters that he cribbed from a meteorologist's blog. What he doesn't do is actually discuss how you measure altitude. Hell, he doesn't even talk about how to read an altimeter, which is definitely more involved than reading your car's gas gauge!

No, Jonra's a scientific illiterate (degrees in liberal arts and computer "science"), and completely skips all the messy stuff. So he never discusses formulas and the other "hard thingies" that explain "how you measure altitude" using barometric pressure. That's probably because he had no idea what the barometric formula is or how to use it to determine altitude from barometric pressure.

Springs neglected to mention radio altimeters, dodged discussion of the mathematics behind measuring altitude and misinformed readers about sea level and the global positioning system. We think that's more than enough reason to honor his work with a Dumbass of the Day award.

¹ The original has been deleted by Leaf Group, but can still be accessed using the Wayback machine at archive.org. Its URL was   ehow.com/how_8245480_do-measure-altitude.html

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