Tuesday, September 16, 2014

Apple #684: Remembering 9/11 -- Shanksville, PA

Last week I had an appointment way on the other side of town before work. I got there early.  Exhausted due to a cold I've been battling, I parked in the lot, locked my car doors, put my seat all the way back, and intended to take a nap.  This particular location turned out to be much closer to the airport than I'd realized, I discovered by the number of airplanes flying over.  They were taking off, each one very loud at first but then slowly fading off into the distance.  After maybe a minute of quiet, here came another one roaring up into the sky.  This incessant noise of airplanes taking off one after another reminded me: it was Thursday, September 11.



(Photo by addicted eyes at Flickr, sourced from TripCart)


So I started thinking about the events of that day as I remembered them.  I was nowhere near New York City or the Pentagon or Shanksville, PA on that day.  Everything I know came to me over the radio or by TV news or in the newspaper.  But because so much of it was broadcast, non-stop, live, and for so long, and mostly because it was so shocking and unbelievable, it is of course stamped on my mind as I'm sure it is for anyone who was alive and sentient on that day.

As I was recalling some of the events of that day, I realized there was a lot I didn't know about the plane that went down in Pennsylvania.  When I got home, I looked it up.  Because the whole "Let's roll" phrase got co-opted by politicians, I didn't pay much attention to the facts of what actually happened at the time.  So the other day I wound up learning quite a lot about what took place on that plane.

I went on to read about all sorts of things -- the hijackers, the contents of the toxic cloud of debris, specific engine houses of the FDNY and how they were affected, and on and on.  Once I'd started, I couldn't get it out of my mind.  I'd turn something over in my mind, imagining it, wondering at it, and discover I had another question.  Back to the internet to find out the answer.

Then I watched a program on the History channel, 102 Minutes That Changed America.  (The interactive thing they have on their website is worth checking out.  It gives you a piecemeal idea of what the documentary as a whole is like.)



Initially released September 11, 2008
(Image of DVD cover from Wikipedia)


It's all videos that were taken by various people on that day at various places around New York City.  The videos have been edited together to be are presented in roughly chronological order.  There is no voiceover, no commentary, only the ambient sound in the videos.  If someone speaks to the cameraperson, you hear that.  If someone shrieks in the background, you hear that.  When the program comes back from commercial, you see a black screen with a running time stamp, and you hear audio from one of the recordings.  Then the visual fades in.

I found myself trying to remember, at what time exactly did the first tower collapse?  Wasn't it 10:02?  So I kept watching.  Even as I remembered that strange, detached, disbelieving feeling -- am I really seeing what I think I'm seeing?  Is that actually happening? --  I wanted to tell the people on the screen who were standing about, staring up at the towers and the black smoke billowing out of them to get moving, go, get out of there.  Because this time around, I knew what was going to happen.  I knew how real it was.  I wanted to take the shoulders of the firefighters as they walked past in a line, in full gear that would be all too insufficient, heading toward the towers to try to get more people out of them.



(Photo from Undicisettembre)


The program goes until some time after both towers have collapsed.  There is hardly anyone in the streets, everything is coated in that terrible thick beige dust that one firefighter said was filled with tiny shards of glass, and everything seems coated in silence.  One cameraperson is walking down some street that is otherworldly and apocalyptic in this way, and out of the haze of debris emerges a large lump the same beige color as the debris.  It's moving, it's a man, covered in the terrible dust.  His hair, his face, his eyeglasses, his shirt, his arms, his legs -- everything about his person is covered in the thick stuff.  He says to the cameraperson, "I heard something give and I ran.  I'm 69 years old, but I can still run."  He continues walking past the camera, his shoulders stooped, probably from a lifetime of work at some desk that is now vaporized, his footsteps making hardly any noise in the dust-thickened street.

After I watched that documentary, it seemed as if it had all just happened.  The sights, the sounds, the emotions were so immediate, all over again.  The next day, I checked the news, expecting to see some sort of follow-up, someone talking about it.  But of course there wasn't much.  This did after all happen 13 years ago, not the day before.  But watching those videos of the planes plowing into the towers, the black smoke billowing out of them, the towers collapsing in on themselves with a horrible feeling of doom that you can feel collapsing in your stomach, and the apocalyptic streets afterward--it all seems to me now to have just happened.

So I've kept thinking about it, remembering things I saw, looking up more facts, learning new details.

I thought about discussing some other topic entirely in this blog post, especially since the spirit of this blog is supposed to be geared toward positive things.  But this has been so on my mind, it seemed flippant to talk about something mundane and silly.  So if I was going to do a post on 9/11, maybe I should give you a list of things that are somehow positive that have come out of the attacks.  But that is so one-sided, it seems almost like telling a lie.  Because what did happen first was awful.  To ignore that, to pretend like the carnage inflicted is somehow not worth mentioning, or is too unpleasant to mention, or should be passed over only slightly, is somehow to betray all those people who lost their lives, all those firefighters who did rescue people from those buildings, all those people who did manage to get out, all those people who still suffer the effects of that horrible toxic cloud of debris and the aftershocks of what happened on that day.



(Uncredited photo posted at Keenly Kristin)


So, what can I tell you?  I think I'll pass along some of the things I've learned in all that I've read and watched over the past few days.  Some of the things you may already know; in fact, many of the things may not be new to you at all.  But these details filled in little gaps in my knowledge, or reminded me of aspects I'd forgotten.  Some of them might be demonstrations of the goodness of people during horrific events.  Some of them might be unpleasant or uncomfortable.  And, fair warning, some of them will be gruesome.  Because those are facts, too, things I've wondered about.  All of it falls under the question: What, exactly, happened?

I'll leave it to you to decide whether you want to continue reading or move along to something elsewhere that is more cheerful, more 2014.

United Airlines Flight 93, crashed in Shanksville, Pennsylvania



Composite of the crew and passengers on board Flight 93.

  • Once the passengers were sent to the back of the plane, they called spouses or loved ones or even 911 on their cell phones or on the in-flight telephones. Because the plane was flying so low, it was possible to establish cell connections.
  • The two planes had already crashed into the World Trade Center, and people on the ground told the passengers about this.  So they realized that the plane they were on had been hijacked for a similar purpose. They took a vote of some kind and decided to try to resist the hijacking.
  • One of several passengers who made calls was a man named Tom Burnett.  He called his wife four times during the flight. She told him about the other hijackings.  He passed the information on to fellow passengers and they decided to resist.  
  • Burnett's wife had once worked as a flight attendant, and she told him to "sit down, be still, be quiet, and don't draw attention to yourself." This is what flight attendants are trained to tell passengers in the event of a hijacking.  But he told her he was "putting a plan together," and that he and other people on the plane were "going to do something." 


Deena Burnett holding a photo of her husband, Tom, one of the passengers involved in resisting the hijackers. For more than a year before the hijacking, Tom had been attending daily Mass, and he believed that God had something important in mind for him to do. This may have been why he was able to keep calm and form a plan during the hijacking.
(Photo from Diablo Magazine)

  • The hijackers had already knifed a passenger and someone else in the cockpit, most likely the pilot. It is likely that they also killed one of the flight attendants when she struggled against them.  The hijackers closed the door to the cockpit as they redirected the plane toward Washington, DC. Meanwhile, after gathering information and coming up with a plan, the passengers apparently attempted to storm the cockpit, rolling the food cart into the door to bash it open.
  • Lisa Beamer was on the phone with her husband, Todd Beamer, who was on the plane and among those who were resisting the passengers.  She said that his final words, which he said while he was on the phone with her, were "Let's roll!"  
  • The hijacker flying the plane, Ziad Jarrah, pitched the nose up and down to shake the passengers and stop their attack. The cockpit voice recorder captured "loud thumps, crashes, shouts, and breaking glasses and plates," and Jarrah apparently assumed he'd thwarted their attack.  But some seconds later, someone shouted, "Roll it!" and the sounds of fighting continued.  
    • By the way, the official report does not include the phrase, "Let's roll," but rather "Roll it." For whatever that's worth.
  • In response to continuing struggles from the passengers, Jarrah said, "Is that it? Shall we finish it off?" and another hijacker answered, "Yes, pull it down, pull it down!" Jarrah pulled the yoke hard to the right, rolling the plane onto its back and it plunged toward the ground, even as sounds of the passengers resisting continued.


Ziad Jarrah, the hijacker who flew United Flight 93 into the ground. This photo really gets to me.  It was taken during his flight training in Florida in 2000. He looks like a pretty normal person, doesn't he?  I've stared at this photo, wondering how does a person go from smiling in a fairly normal way to hijacking a plane and killing scores of people.  Jarrah was born in Beirut, Lebanon, to an upper middle class family.  He, like the other hijackers, seemed normal, courteous, and friendly to Americans who met him in the years before the hijacking. One researcher who has studied the hijackers hypothesizes that it was becoming obsessed with religion, specifically with a doctrine that emphasized revenge and attacking others, that changed them.
(Photo from Wikipedia)

  • The plane plowed into the ground at 580 miles per hour, in an empty field in Shanksville, Pennsylvania, about 20 minutes' flying time from Washington, DC.
  • The impact was so great, followed by four explosions, the fire chief in the Shanksville Fire Department felt the ground shake.  In the fourth grade classroom of a nearby school, the ceiling tiles bounced and settled again.
  • Nearly all of the plane and everyone on it were blown to fragments. The coroner said, when he examined the crash site, the only recognizable body part he saw was "a piece of spinal cord with five vertebrae attached."  However, he never saw a single drop of blood. "The only thing I can deduce," he said, about why there was no blood visible anywhere, "is that the crash was over in half a second. There was a fireball 15-20 meters high, so all of that material just got vaporized." 


Flight 93's impact site. It looks like a bunch of burned dirt because when the plane hit the ground, large sections broke off, and the explosions burst those to fragments. The rear of the plane was driven into the ground, and the loose soil collapsed in around it, effectively burying it. (See On Hallowed Ground)
(FBI - investigation photo sourced from NPS site)

  • The passengers on Flight 93 never would have known about the other planes, and probably would not have resisted, had their flight taken off according to schedule. Flight 93's take-off was delayed 42 minutes because of too much air traffic at the airport in Newark.  Had the flight not been delayed, the passengers never would have known anything about the other flights and Flight 93 might have gone on to the hijackers' destination.
  • It was thought that this flight was intended to hit the White House, and that plan was actually discussed.  Interviews and testimony after the crashes revealed that it was probably intended to hit the US Capitol instead, which is more easily visible from the air.
  • 8 days after the crash, all the passengers and crew of Flight 93 were nominated for the Congressional Gold Medal.  It took until this year, 2014, before the medals were actually awarded. 
  • The Congressional Gold Medal is Congress' "highest expression of national appreciation for distinguished achievements and contributions." 


The Congressional Gold Medal awarded to the crew and passengers of Flight 93 that crashed in Shanksville, Pennsylvania, rather than into the US Capitol, thanks to their resistance.
(Photo from Coin Update)



Congressional Gold Medal awarded to the crew and passengers on the flight that crashed into the Pentagon, and to the people on the ground who were killed.
(Photo from Coin Update)



The Congressional Gold Medal awarded in honor of those killed at the World Trade Center towers. The numbers 11, 175, 77, and 93 on the front of the coin are the flight numbers of the planes that were deliberately crashed, and they are positioned as if on the face of a clock, at about the times when the planes crashed.
(Photo from Coin Update)






The site of the crash of Flight 93 is now a memorial site.  There is a large plaza with a walkway that leads to a wall bearing the name of each crew member and passenger. The entire memorial is surrounded by a field of wildflowers.


(Photos from the National Park Service Flight 93 National Memorial)



Their names are also engraved in bronze at the 9/11 memorial site in New York City.
(Photo by Amy Dreher, from the 9/11 Memorial)




That's all I can do for today.  I guess I'll have to break this into multiple posts.  Which means the flight that hit the Pentagon will be next.


Sources
National Commission on Terrorist Attacks upon the United States, "We Have Some Planes"
Tom Burnett Family Foundation, Transcript of Tom's Last Calls to Deena
The Age, "Let's roll": A catchphrase that became a battlecry, September 9, 2002
The Age, On Hallowed Ground,  September 9, 2002
Diablo Magazine, "This is Not my Life. My Life is Quiet, Suburban, and Ordinary." August 26, 2011
The Washington Post, The 9/11 Hijackers: Perfect Soldiers, May 1, 2005
Philly.com, Flight 93 families honored, and thanked, at U.S. Capitol (article)Flight 93 families honored, and thanked, at U.S. Capitol (photos), September 11, 2014
US House of Representatives, Congressional Gold Medal Recipients

Sunday, September 7, 2014

Apple #683: Days of the Week

I was thinking about doing a Daily Apple on Tuesday.  Wednesday is hump day, Thursday is now apparently throw-back Thursday, Friday is the end of the work week, but what about Tuesday?  No one pays any attention to Tuesday.  Except sometimes there are two-for-Tuesday things.

I wondered what Tuesday is named for.  I don't know if I was taught this way, or if this is something my brain came up with on its own, but I thought that the days of the week were named for Roman gods.  Saturday is named for Saturn, obviously.  The other ones I was less sure about. Thursday must be named for Thor -- not Roman, but still a mythological god.  Friday was maybe named for Friya.  But again, what about Tuesday?  Could there be some relationship to the word "two?"



Days of the week -- in bottlecaps
(Photo from BeansThings on Flickr)



Wrong. Some of my assumptions were actually correct, but for wrongity wrong reasons.  Saturday is in fact named for Saturn, but, oh, let me show you what I found out.

  • The days of the week are named for the planets in our solar system, including the sun & the moon. (The planets are named for gods, so there's some overlap here.)
  • This is more obvious in the Romance languages than it is in English. 
  • Let me show you with a table.  Blogger is terrible at handling tables, so I hope this turns out OK.

 
Day Celestial Body French Spanish Italian
Sunday Sun Dimanche Domingo Domenica
Monday Moon (Luna) Lundi Lunes Lunedì
Tuesday Mars Mardi Martes Martedì
Wednesday Mercury Mercredi Miércoles Mercoledì
Thursday Jupiter (Jove) Jeudi Jueves Giovedì
Friday Venus Vendredi Viernes Venerdì
Saturday Saturn Samedi Sábado Sabato

  • It's really easy to see where French, Spanish, and Italian used the names of the planets for their days of the week.  The only one that doesn't quite fit is Sunday.  In these languages, their word for Sunday means "Day of the Lord."
  • I suppose if the Earth's rotation had allowed for more days of the week, we'd also have days named after Uranus and Neptune and maybe even Pluto.
  • But hang on a minute.  The order of the planets in this list does not correspond with the order in which we usually think of them, in terms of their distance from the sun.

 
Nine planets (minus Pluto) and their position relative to the sun. This is not how our days of the week are ordered.
(Image from Nine Planets)

  • Here is what some people have proposed as the reason for this order.  Put the celestial bodies in our list in a circle, assuming Earth is at the center.  Order them according to their time of revolution around the earth, and you get this:

(Diagram from The Calendar FAQ)

  • OK, now start with the moon (Monday), and count one position clockwise around the circle for each hour of the day: Saturn 1, Jupiter 2, Mars 3, Sun 4, Venus 5, etc.  Stop when you hit 24 and your finger will be on Mars.  The next day of the week.  Do the same thing again, beginning with Mars, and the 24th position will be Mercury. And so on until you have the planets listed in the order we've seen above.
  • Pretty clever, eh?
  • So why don't our words for days of the week look like those French & Spanish words?   Why isn't our Tuesday more like Mars Day?
  • Answer: because of that whole Old English thing.

Celestial Body Old English Current English
Sun Sunne Sunday
Moon (luna) Mona Monday
Mars Tiu Tuesday
Mercury Wōden Wednesday
Jupiter (Jove) Þunor Thursday
Venus Frigg Friday
Saturn Saturnus Saturday

  • You can definitely see the similarities between Old English and our present-day English.
  • But it sure seems like a big leap from "Mars" to "Tiu," and from "Mercury" to "Wōden." And what's that weird letter Þ?
  • Tiu -- sometimes spelled Tiw, this was the name of the Old English/Germanic god of war.  Mars was the Roman god of war.  Tiu's name is a descendant of the old Norse name for their god of war, Tyr.  Just as people say the Roman god of war, Mars, and the Greek god Ares were the same thing (though they kind of weren't), so you could also say that Tiu and Mars were pretty much the same gods. Tiu is also known as the god of hand-to-hand combat, heroism, and justice.


This is Tiu, or Tiw.  He was kind of a bad-ass.  There was a seriously bad wolf, Fenrir (hello, Harry Potter fans) whom the gods were trying to tie up and subdue. The wolf said he would never give up unless one of the gods put their hand in his mouth. Tiu was the only god who had the guts to do so.  The dwarves made a magical ribbon and the gods used it to bind up the wolf, but not before he'd bitten off Tiu's hand. So Tiu is often depicted as being one-handed.
(Image from Saxons and Vikings in Britain)


  • Wōden -- this is another descendant of a Norse god, in this case, Odin.  Wōden was an Anglo-Saxon god who was the big cheese, in charge of all sorts of things. He created the earth and sky out of the body of a dead giant, he made the first man and woman, and he made the laws that govern the universe.  You'd think that would make him like Jupiter/Jove, but he was also the god of learning, poetry, and magic. So he got correlated with Mercury, who was the god of poetry, communication, speed, trickery, and the escort to Hades.  Tiu (or Tiw) was one of his children.


This is Odin, the Norse god whose Anglo-Saxon counterpart was Wōden. Odin was seriously cool. He's flanked by his two ravens, Thought and Memory, who flew off and came back to him with news of each day's events. It's hard to see it in this drawing, by he's often shown missing one eye because he agreed to lose one for the privilege of drinking from the fountain of wisdom.
(Image from U Colorado Mythology Course)


  • Þunor -- First of all, that weird letter Þ is called a "thorn." It's from the Old English alphabet and it's pronounced th. So you'd say this name Thunor.  Looks like thunder, doesn't it?  This is the Anglo-Saxon god whose counterpart in Norse mythology is Thor, who was the god of thunder, lightning, storms, oak trees, strength, and war. (I'm beginning to wonder, who wasn't a god of war?)  Þunor was another son of Wōden's. 


Þunor, or Thor, using his hammer to fight off the giants. In addition to all those other strong-man things, he was also the god of protection of humankind.
(Painting by Winge, 1872, from Wikipedia)
 
  • Frigg --  Frigg was the wife of Wōden. Sometimes her name is spelled Frigga. Some say she is not the same goddess as Freya; others say she is very similar and so might be the same.  She is the goddess of love, marriage, and motherhood.  She weaves the web of destiny, so she knows everyone's fate, but she does not reveal it. This may explain why Friday is such an exciting day of the week.


Frigg, goddess of love and marriage and motherhood, and also weaver but not revealer of destinies. She looks like she knows more than she's telling, doesn't she?
(Image from Norse Gods and Goddesses)

  • The rest of the days -- Sunday / sun; Monday / moon; Saturday / Saturn -- seem pretty obvious, so I won't go into them in detail. You get the picture.
  • You might be thinking, well, this is only Western cultures that have named their days of the week this way.  
  • It is true that in many other languages, the days of the week are simply numbered -- 1st day, 2nd day, 1st day off, 2nd day off.  
  • But take a look at the days of the week in Japanese:



Orthography Romanization Translation
Sunday  日曜日  nichiyōbi  Sun day
Monday 月曜日  getsuyōbi Moon day
Tuesday  火曜日  kayōbi Fire day
Wednesday 水曜日  suiyōbi Water day
Thursday  木曜日  mokuyōbi Wood day
Friday  金曜日  kin'yōbi  Gold day
Saturday 土曜日  doyōbi  Earth day


  • You might think at first that this is a completely different method for naming the days of the week -- at least, except Sunday & Monday.
  • But if we look at these names through the lens of the Chinese theory of the five elements (yes, I know Chinese and Japanese culture are two different things, but they did borrow things from each other quite often), you start to see something pretty familiar.  Remember, the Japanese terms are elements.
    • Fire -- the color red, south, summer, midday, and the planet Mars
    • Water -- the color black, north, winter, midnight, and the planet Mercury
    • Wood -- the color green, east, spring, dawn, and the planet Jupiter
    • Gold -- the color white, west, autumn, dusk, and the planet Venus
    • Earth -- the color yellow, the center, the end of each season, and the planet Saturn
  • Adding those definitions to our chart, we get this:


Orthography Romanization Translation Celestial Body
Sunday  日曜日  nichiyōbi  Sun day Sun
Monday 月曜日  getsuyōbi Moon day Moon
Tuesday  火曜日  kayōbi Fire day Mars
Wednesday 水曜日  suiyōbi Water day Mercury
Thursday  木曜日  mokuyōbi Wood day Jupiter
Friday  金曜日  kin'yōbi  Gold day Venus
Saturday 土曜日   doyōbi  Earth day Saturn

(with thanks to Bathrobe's Days of the Week)

  • Again, pretty cool, eh?
  • By the way,  the days of the week in Chinese (Mandarin), are essentially numbered, as in ritual-day one, ritual-day two, ritual-day three, etc.  
  • However, there is one old set of names in Mandarin for the days of the week that nobody uses anymore, and that set is based on the planets.  
  • The theory, very speculative, is that the planet-based names originated in ancient Mesopotamia and Egypt. That tradition was picked up on by the Greeks and Romans and spread through the Western world. It also traveled westward to cultures in Persia, the Middle East, and Central Asia, and eventually reaching China and Japan.


Sources
Oxford Dictionaries, Just Plutonic? Roman gods and their relationship to the days of the week
Bathrobe's Days of the Week, In the West, Japanese, Chinese
The Calendar FAQ, The Week
Lawrence A. Crowl, The Seven-Day Week and the Meanings of the Names of the Days
Calendars through the Ages, Our Seven-day Week
Infoplease, Woden
Behind the Name, Þunor and Thor
Encyclopedia Mythica, Frigg
Norse Mythology for Smart People, Frigg

Monday, August 25, 2014

Apple #682: Dog Days of Summer

It has finally turned humid this summer.  For weeks and weeks, the weather has been beautiful -- sunny, breezy, warm, and none of that oppressive humidity.  But a few days ago, we had a big fat thunderstorm, and it left a lot of that humidity behind.  Looks like it won't budge for the whole week, either.

Which makes me think, we have finally entered the Dog Days of Summer.

What does that mean, anyway?  I have always imaged it means this:



(Photo from Doggie Cakes)


(Photo by Snowlight at Flickr, sourced from Low Country Dog)


(Photo from The Pet Wiki)


The Dog Days of Summer: when the weather gets so hot, all the dogs are panting.

But no, that is not the correct definition.
  • The Dog Days refers to the position of Sirius, the dog star (No, not Sirius Black), relative to the sun.


Sirius is the brightest star in the constellation Canis Major (Bigger Dog). It's just below Orion -- the 3 stars of Orion's belt point to it.  The story goes that Canis Major is Orion's hunting dog.
(Image from Space.com)

  • Ancient Romans noticed that during the hottest time of the summer, the brightest star in the night sky -- Sirius -- was rising and setting roughly the same time as the sun. 
  • Some people say the Romans thought that Sirius's conjunction with the sun was adding heat to the days, and that's why those particular days were hotter.  
  • In reality, while Sirius is the brightest star in the sky, it is much too far away for its heat to have any impact on us.  


Sirius is larger and brighter and hotter than our sun -- though it's too far away for us to feel its heat.
(Image from Astro Bob)

  • The Romans were pretty smart cookies, though, so they may have known this and simply been aware that the two were in the sky at the same time. 
  • Ah, yes, here we are.  An astronomer named Geminus wrote, around 70 B.C., "It is generally believed that Sirius produces the heat of the 'dog days,' but this is an error, for the star merely marks a season of the year when the sun's heat is the greatest." 
  • (So, Weather Channel and everybody else, quit making the Romans out to be a bunch of dummies.)
  • Knowing that the two stars were in the sky at the same time, the Romans named that stretch of days the Dog Days of Summer. (Actually, the time period goes from about 15 days before the two rise together through 15 days after)
  • Exactly what part of summer that happened is also now in question.  Because of the very slow change in the Earth's orientation on its axis, when Sirius rises with the sun now is slightly different than when it rose back then. 
  • Some say it used to happen from July 23 though August 23, or thereabouts.
  • Now, however, the Farmer's Almanac says the Dog Days officially happen each year from July 3 through August 11, and everybody more or less goes along with that.
  • You kids with your smart phones, you've probably got an app that allows you to point your phone at the sky and it will tell you where the constellations are.  If you don't, this app called Star Walk ($2.99) supposedly does just that. Get an app like this, and you can see for yourself where Sirius is, and whether we're actually in the Dog Days or not.
  • (I know, he fell through the portal and he isn't coming back.)

Monday, August 18, 2014

Apple #681: Airport Runway Signs

I have had a request!  Daily Apple reader Jamarcus wants to know, what do all those signs next to airport runways mean?  You know, the ones that look something like this:


This sign lights up so it will be visible to pilots at night. But what do the letters and numbers mean?
(Photo and sign from Astronics Corporation)


A very good question.  Something I have often wondered myself.

Before you can interpret the signs, it helps to know how things get named at airports.

Taxiways

  • There are taxiways, and there are runways.  Runways are the paved strips where planes take off and land.  Taxiways are the paved passageways the planes take to get from the terminal to the runway to take off, or from the runway where they've landed back to the terminal.
  • You definitely want to keep the two separate because you don't want one plane ambling down a runway as another plane is about to land there.
  • A lot more real estate is covered by taxiways.  Some of our airports are enormous, and a plane may have to travel quite a long way to get from the terminal gate out to the runway.  It will have to drive down a lot of taxiways before it gets to the runway.
  • Taxiways are indicated with letters, beginning A, B, C, etc.  All airports begin their naming of taxiways with A, and one taxiway can go for a really long way. So the signs you see from your airport window will most often have an A on them.  
  • Some airports are so big or have so many taxiways, they get up to G.  Theoretically, taxiways could be lettered all the way up to Z, and then get the letters doubled: AA, BB, CC, etc.  But in real life, it's rare that taxiways are named much deeper into the alphabet than G.
  • Taxiways can never be named H.  The letter H is reserved for helipads -- landing places for helicopters.
  • They can also never be named I or O, because those letters could be mistaken for numbers.
  • They can also never be named X because an X on a sign means the runway or taxiway is closed.
  • You will often see signs that combine a letter and a number, such as A1, or B3 (as above), or C2.  These indicate either:
    • a stub taxiway -- a connector that goes from a runway to a taxiway that runs parallel to the runway (a little cross-bar connector from a runway to a taxiway) 
    • or the exit or entrance connector that goes from a taxiway to & from the terminal. The connectors get named sequentially A1, A2, A3, etc. along the length of the taxiway.
  • Keeping all those rules in mind (and a few I've left out for brevity's sake), an airport also needs to make sure no taxiway has a name that could be confused with a runway, and no two taxiways have the same name. 


Well, this is hard to see. But the runways have the dashed lines, and the taxiways are thinner.  The taxiways are named, from top to bottom, A, B, and C, and the little connectors that go between the runways and the taxiways are named, from left to right, A1, A2, A3, A4, A5, A6, and A7, and then in similar fashion for the connectors that go off taxiways B and C.  The little taxiway that goes vertically, bisecting the runways and the parallel taxiways, is named J.  That one gets its own letter, as opposed to something like C5, because that's a high-traffic taxiway.
(Diagram from the FAA's Engineering Brief on Taxiway Nomenclature)



This isn't a real-life runway but a screen shot from a simulator, but it does the job for our purposes.  The runway is on the right, as indicated by the white markings. The taxiway, outlined in yellow, is on the left.  A taxiway stub connects the two.  The colored paint and types of markings is a whole other set of visual indicators for pilots.  
(Photo from SimFlight)

  • By the way, the names of taxiways are not pronounced as the letters (A, B, C), but by the names that correspond to each letter, according to the NATO phonetic alphabet (Alpha, Bravo, Charlie).   So taxiway A2 would be called "Alpha two."
  • Yes, this is the same alphabet popularized by Wilco's Yankee Hotel Foxtrot.

Runways

  • Runways get named using numbers.  The thing that determines which numbers get assigned to a runway is where the runway is relative to points on a compass.  Then it gets turned into a kind of code.
  • North, South, East, and West all correspond to degrees on a compass.  North = 360°, for example.  According to this runway code, you lop off the 3rd digit of the compass point.  So if a runway were pointing true north, it would get numbered 36.  For the 4 points of the compass, the code works like this:
    • North = 360° = runway number 36
    • South = 180° = runway number 18
    • East = 90° = runway number 9
    • West = 270° = runway number 27
  • But of course it's rare for a runway to be heading in exactly the position of one of the points of the compass.  So in most cases, the runway number is arrived at by rounding off ±5°.  Let's say a runway is heading 176°.  That's within 5° of 180°, so its runway number would be 18.
  • It is also of course likely that a runway won't fall within 5° of one of the ordinal points on a compass, so it is very likely that runways will be named other numbers besides these four.
  • Because there are only 360° on a compass, you can't have a runway with a number higher than 36.  Also, since North is indicated by 360°, there is no 0°, so there will be no runway named 0.
  • Finally, because you may be allowed to land on a runway from either direction, its name will often be expressed from either approach direction, as in ##-##.  The first number indicates the compass direction from one end of the runway, let's say, 22.  That means the runway's compass heading is 220° (or within ±5° of that).  So the second number will be 180° from 220°, which is 40°, which becomes number 40.  This runway's official name is therefore 22-40.
  • By the way, the runway numbers are not pronounced the way we normally pronounce two-digit numbers. They are said individually.  Not "runway twenty-two" but rather "runway two-two." Nine is pronounced "niner."  Yes, just like in Airplane!

Signs

  • Now that you know what the letters and numbers mean, let's look at some signs.


(Photo and sign from Astronics Corporation)

  • This is our sign from earlier.  Now we know that B means "Taxiway Bravo" and B3 indicates a taxiway stub or connector or exit.  Anything in a black box with a yellow outline means "this is where you are."  So this sign means "You are on Taxiway Bravo. Taxiway stub Bravo three is to the right."

(Photo and sign from Astronics Corporation)
 
  • Here's another one. This means "You are on Taxiway Alpha.  Taxiway Foxtrot is to the left or angled to the right."


(Image from Avery Dennison)

  • Let's try a little more complicated one.  This one means, You are on Taxiway Hotel 3, Taxiway Charlie is to the left, Taxiway stub Charlie two is angled to the upper right, and more of Taxiway Charlie is to the right.
  • The red circle with the white line through it means "CLOSED."  This sign seems to be saying a little too softly that Taxiway stub Charlie two is closed, but that's what it means.  
  • (I think in this case, Avery Dennison, a label-making company, is saying you could put one of our  temporary "CLOSED" sticker on your runway signs.  Really, the airport should put up a giant CLOSED sign and they're also supposed to paint big red Xs on the ground before a closed section.)


This is what a CLOSED, or NO-ENTRY sign should look like. Either this or a gigantic X. Big and obvious. No subtlety. 
(Image from the Aircraft Owners and Pilots Association

  • Those yellow signs are the kinds you see most often. Taxiway Alpha's exit is this way, etc.  Now that you've got those down, you'll be able to interpret most of the signs along the taxiways that you'll see from your airplane window.
  • But there may be other signs in other colors and letters.  What about those?


(Image from Holland Aviation)

  • By now you know the part in the black box means "You are currently on Taxiway stub Sierra six."  The stuff on the right you might guess indicates a runway named either "two four or zero six." You are correct about that, but since it's in red, it also means a whole other thing.
  • Red signs mean "stop" or "holding position."  This means the plane has to stop right here and wait until it gets the go-ahead from air traffic control to proceed onto the runway.  There will also be some yellow & black markings like crazy on the pavement next to the sign.  The plane is absolutely not to cross those yellow and black lines at all until the pilot gets the OK.


(Photo from Airchive)

  • What about this one?  It's a red sign, so you know it means stop, but there are no numbers on it, only the letters ILS.  That can't mean a taxiway, right?
  • Right.  ILS stands for Instrument Landing System.  This is the signalling system used by air traffic control to give pilots precise information about taking off from a runway, or landing on it.  The red ILS sign means this is a critical ILS zone, and "stop here and wait or you will interfere with ILS signals being given to planes taking off or landing on this runway."


(Image from the Aircraft Owners and Pilots Association)  

  • You might also see a red sign with two runway numbers followed by the letters APCH.  That stands for "Approach."  Like the ILS sign, this means you've entered the approach for a particular runway (runway 15, in this case), and you must wait here so you don't interfere with the ILS signals for incoming planes.


(Photo from Air News Times)

  • This image is kind of dark, but anyway, what does FBO mean?  That's not a taxiway either, right?
  • Right.  FBO means "Fixed-base operator."  It's basically the gas station for airplanes.  FBOs are typically businesses that operate independently of the airport -- Chevron, or Philips 66, or some other gas company -- but that serve airplanes at the airport.  They provide fuel for the planes, and they also may provide maintenance services, hangars, parking, equipment rental, and so on.  They are used most often by people who fly their own planes.


(Image from the Aircraft Owners and Pilots Association

  • This one you don't see very often, but MIL means a military installation is that way.
  • I think that about covers it.  Thank you for flying with the Daily Apple today.  Enjoy your destination.

Sources
FAA, Airport Marking Aids and Signs
FAA Engineering Brief No. 89, Taxiway Nomenclature Convention
Jim Sweeney, The Short Course: Airport Signs
Aircraft Owners and Pilots Association, Airport Signs and Markings
Nevada DOT, AOPA's Airports Signage & Markings (this uses the terms runways and taxiways interchangeably, which is very confusing)
AOPA's runway flash cards
Bangalore Aviation, Airport runways: All you wanted to know but were afraid to ask
Sploid on Gizmodo, This is what all the signs and symbols at the airport runway mean
Alpha Bravo Charlie.info
 

Monday, August 4, 2014

Apple #680: Henna Tattoos

This weekend at the state fair, I got a henna tattoo.



I went for a simple $8 design of a sun. The tattoo artist offered to extend it so it goes up my finger. I said OK by me.
(Photo by the Apple Lady)


Naturally, I asked the woman who gave me the tattoo all sorts of questions about it.  And again naturally, I have still more questions.  So here follows some of the things she told me mixed in with some of the things I looked up and have learned since.

What Is Henna?

  • Henna is a dye made from the ground-up leaves of the henna plant (Lawsonia inermis).  
  • It's sometimes also referred to as mehndi or mehandi or mendhi.


The henna plant is a pretty non-descript looking shrub.
(Photo from Sailu's Kitchen)


  • The plant is a flowering shrub that grows in all sorts of places, including the US and Australia, but it's most prevalent in the dry, arid regions in northern Africa, India, and the Middle East, and it also grows in Southeast Asia.
  • The leaves themselves won't stain anything; you have to crush them or grind them up before they will work as a dye. Most people make their henna dye from powdered henna.
  • Henna has been used as a dye for both hair and skin for centuries in several different cultures & religions in the areas where it grows.
  • Though people of Muslim, Hindi, Jewish, and other faiths have all used henna, they all generally consider that henna tattoos mean some sort of good luck or blessing. 


Traditional bridal mehndi -- henna tattoo on the hands & wrists prior to a marriage, here, on a bride from India.
(Photo from Sameera Threading)

Why it's Usually Brown, and Why on the Hands & Feet

  • Traditionally in most of these cultures, women's hands or feet, or both, were tattooed before a wedding as a way to invoke good luck for the bride or the marriage.  But now lots of people get henna tattoos for lots of purposes.
  • It takes a while for the henna stain to sink into the skin.  So you don't know right away how dark the tattoo will be.  The stain can range from tan to light brown to auburn to dark brown.  
  • What color the tattoo becomes depends on the person's skin, where on the body the tattoo is applied (some areas take up the stain better than others), how much henna is present in the stain mixture, whether the henna artist has used some form of mild acid like lemon juice or vinegar as an adjuvant, etc. 
  • Because the color of the stain varies from one person to another and from one application to another, the darkness of the tattoo is consider to signify the extent of the good luck. In other words, the darker the henna tattoo, the better your luck will be.  So the theory goes. 
  • Most henna tattoos are put on the hands and feet.  This is because the skin here tends to be thicker, so it will absorb more of the henna, and the resulting tattoo looks darker than it would elsewhere.  
  • Back of the hand and top of the feet works best because it's easier to keep from disturbing the henna paste as it dries and interrupting the process by which the paste stains your skin.  But people do put henna tattoos in lots of places--palms, shoulders, calves, bellies, etc.


This henna tattoo starts on the fingers, descends down the palm, and onto the wrist. You can see how the tattoo is darker on the fingers and palm than it is on the wrist. This is because the skin on the wrist is thinner and doesn't take up the stain as well as on the hand.
(Photo from Ohio Body Art)


What It's Made of

  • Most henna artists mix the powder into a paste. Typical ingredients include:
    • henna powder
    • black tea or coffee
    • lemon juice or lime juice or orange juice or vinegar (mild citric or acetic acid)
    • sometimes the lemon juice etc. is mixed with sugar
  • That's it. People say the resulting paste feels like toothpaste.  In my very limited experience, the paste that was put on me felt smoother even than toothpaste. More like gel toothpaste.
  • The henna plant is not toxic, and neither are any of those above ingredients. (The situation is a little different for "black" henna, but I'll get to that in a bit.)
  • The paste is applied to your skin, usually through a tiny little tube, sort of like a minuscule cake decorating tip.  There are no needles, nothing is injected into your skin, it is not a painful experience at all. In fact, it's rather soothing. 


This applicator is like what my henna tattoo artist used.  Most of the applicator is a slender metal cone which tapers to a fine point with a hole in the end. At the top end of the applicator is essentially a plastic bag containing the henna paste. The artist squeezes the bag which makes the paste come out the tiny little hole at the bottom. The artist moves the applicator while squeezing out the paste. Often the artist makes very detailed designs and fine lines. I was pretty impressed with the delicacy of the skill.
(Photo from ehow)



This is another type of henna applicator. Here, instead of a little plastic bag, the receptacle that holds the paste is a plastic bottle.  The tip of the bottle is the very fine tube with a tiny hole at the end through which the henna paste emerges as it is squeezed out and applied to the skin.
(Photo from Wikimedia Commons)

  • Since nothing is injected into your skin, some people say it's technically not a tattoo. 
  • The stain sinks down into only the first few layers of your skin, all of which are dead skin cells.  As these skin cells are naturally worn away, so also will the henna tattoo. That's why it only lasts a couple of weeks. 

The Application Process

  • The paste goes on black.  You leave it on, allowing the paste to dry and so the stain has time to sink into your skin.


Henna paste being applied. Here you can see how it sits on top of the skin.
(Photo from White Ink Tattoo Center)

  • You'll want to let the paste dry for anywhere from 4-8 hours. The range of time depends on the mixture your artist is using, how hot & humid the weather is, if you've got lotion on your hands (or wherever the tattoo was applied), etc.
  • This means you won't want to wet your hand--or foot or wherever you got the tattoo--during that drying time. So this is why people tend to get their henna tattoo on their non-dominant hand. 
  • You'll also want to avoid brushing it against things, which will rub the paste off, or flexing and moving that part of your body very much. 
  • When the paste dries, it will flake off in bits.  Some of those bits got on my sheets and left faint brown stains. I washed my sheets right away and the stain came out, no problem.
  • After the dried paste flakes away, the brown stain on your skin will become visible.  Over the next day or two, the brown stain will continue to darken somewhat.
  • You'll still want to avoid washing the area that's been tattooed for about 24 hours.  After that, you can wash your hand, but you'll want to avoid any vigorous scrubbing.  The more scrubbing, the more of those dead skin cells you'll wash away, and the faster your tattoo will fade.


Process of a henna tattoo, from paste to no-paste to additional darkening.
(Image from New World Henna)


This is what the paste looks like as it's drying & flaking off -- kind of crusty.
(Photo from Cuded)



Some of the designs can be really elaborate.
(Photo from White Ink Tattoos Center)



Or even more elaborate. This person would have to keep from moving both of her hands for several hours in order for this tattoo to turn out properly.
(Photo from ehow)



Henna on feet & toes -- also very detailed.
(Photo from Lovetoknow Tattoos)



Some pregnant women get henna tattoos on their bellies--I suppose in hopes of giving good luck to their forthcoming babies.
(Photo from Pop Sugar)


 
This might be a cool idea for someone going through chemo.
(Photo from Best Tattoo Designs Ideas)


Black Henna

  • In most photos of henna tattoos online, the henna looks black. I'm going to assume that this is probably because the picture was taken right after the henna was applied, before the paste dried.
  • However, there is a thing people call black henna.  This type of henna leaves behind a much darker, blacker stain after the paste dries and flakes off.  
  • The ingredient that gets added to the henna that turns it black is a chemical called paraphenylenediamine, or p-phenylenediamine, or PPD.
  • PPD is a type of coal tar that's been used for many years in hair dye, especially for brunette & black dyes. 
  • Some people are allergic to PPD.  If you are allergic to PPD, you do not want this stuff to touch your skin. It is possible to develop an allergy to PPD after having been exposed to it over time. This is why the hair dye people want you to do a skin test before each self-dyeing session, to make sure you haven't developed a PPD allergy.
  • But since henna is used to dye hair as well as skin, people thought, why not add the PPD that we've been using in hair dye to the henna, to make it darker?
  • It turns out, this isn't such a hot idea because for those people who are allergic to PPD, they experience some pretty unpleasant results with the black henna tattoos.

You can see that this woman from Kuwait got a really beautiful henna tattoo. Except the henna that was used had PPD in it, and she turned out to be allergic to PPD. So her skin turned red and swelled up every place the black henna was applied.
(Photo from Evans et al., New England Journal of Medicine

  • Since it takes quite a few hours for the henna to soak into the skin, it can also take that long before people discover they are allergic to the PPD in black henna. So, often the artist using black henna does not know if one of his or her clients has had a bad reaction to the black henna.
  • The best thing to do, therefore, is to ask your henna artist if he or she uses black henna.  If you know you're allergic to PPD, ask if he or she would use the regular henna instead. 
  • If you get a black henna tattoo and then discover you're allergic because your hand is tingling and itching and swelling up like a beautifully decorated basketball, go to your doctor as soon as possible. Most likely, your doctor will prescribe some sort of steroid that will take down the swelling.
  • If the reaction and the swelling are severe, you could wind up with permanent pigmentation -- your temporary black henna tattoo would become permanent.
  • Even if you think you're not allergic to PPD, it's probably best to avoid the black henna.

Now I'll show you some more pictures of regular henna tattoos because there are a lot of really magnificent ones.



(Photo from Factortruth



(Photo from Henna Tattoo Body Art)



Foot henna
(Photo from Cuded)



Leg henna
(Photo from Cuded)


Some henna tattoo artists are also adding additional dyes to make the henna different colors.
(Photo from Tattoos Time)



I think this one wins the prize. This is a wedding henna tattoo, complete with all sorts of colors, glitter, and body art gems.
(Photo from Crafty Nitti)


Sources
Desdemona's Designs Ohio Body Art, FAQ
Henna Arts, Frequently Asked Questions
The Henna Page, Why doesn't henna stain last forever like a tattoo?
Henna Mehndi, How to Mix Henna?
HennaTattoos.com FAQs
FDA Consumer Information, Temporary Tattoos May Put You at Risk
Colby C. Evans, and John D. Fleming, Allergic Contact Dermatitis from a Henna Tattoo, The New England Journal of Medicine, 2008; 359:627