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The remarkably successful evacuation of Asiana 214 compels me to write a post in appreciation of flight attendants who have the toughest job at the airline.

Pilots enjoy the fun and challenge of handling the fancy machine. By the time we get into an airliner we are very familiar with the environment of airports, air traffic control, etc. In the Canadair Regional Jet that I flew we enjoyed about half of the fresh cold air produced by the “packs” while the 51 folks in the back sweated. We had comfortable chairs and our own escape if we decided that we needed to leave those chairs in a hurry. Unruly passengers in the back? We could just lock the door and clutch our weapons (crash axe that came with the airplane; federally issued 10mm pistol that most of the captains seemed to carry (our airline was founded and based in Northern Kentucky so carrying a gun was as natural to most of these guys as carrying a phone)).

How about the flight attendants? They suffered from the same sleep deprivation and crummy hotels that we did but weren’t logging multi-engine turbojet time. With up to 50 passengers on each flight there was always a chance that someone would be upset. I remember a day when a few thunderstorms had resulted in three-hour delays at JFK. A passenger was grousing that JetBlue wouldn’t be stuck in the long line that we were in (had he been able to see through the windshield he would have seen a JetBlue Airbus right in front of us). One one flight we heard a woman shrieking through the locked door. After landing we learned what the trouble was. The flight attendant had started serving snacks from the back of the airplane. As we were a wholly owned subsidiary of Delta (based in Georgia) the two choices naturally included a bag of peanuts. So about 20 of these bags had been opened by the time the 23-year-old flight attendant reached the front row. The shrieking was from a mother traveling with her two boys who were, in her opinion, so allergic to peanuts that the vapors from the previously opened bags would likely kill them. The flight attendant tried to explain that folks with peanut allergies were supposed to call ahead and the airline would wipe down three rows of seats with alcohol and not serve peanuts during that particular flight, but a stream of abuse continued to issue from the mother.

[The boys walked off the plane, by the way, without showing any ill effects from the peanut-suffused environment.]

The real challenge of being a flight attendant is getting people out. The training requires that they demonstrate they can evacuate an aircraft within 90 seconds, but of course a lot of stuff that is easy to do in training turns out to be tough in practice. So this posting is my thank-you note to flight attendants everywhere and to the Asiana 214 cabin crew in particular.

Friends visiting from California invited me to the Westin near Copley Square for breakfast. A girl who seemed to be 2-3 years old was playing with her mom. She spilled some of the mom’s coffee and, while the mom went to get napkins to wipe it up, ran and hid behind my chair, a huge smile on her face. The mom came back and called for her child, working herself into a loud state of panic within about 15 seconds after the first call. I finally caught her eye and gestured that the girl was hiding behind me. The mom was relieved and lightly scolded the girl. The lobby of the Westin is on the second floor of a big tower. If the girl did not get on an escalator she could not have gotten very far. I asked the mother what she had been afraid of. She replied “A stranger taking her.” I asked “How long do you think you’d have to leave a child unattended before there was a 50 percent chance that she would be abducted by a stranger?” The mom’s answer was “5 minutes.”

This got me wondering what the real answer might be. http://www.unh.edu/ccrc/pdf/MC19.pdf is a U.S. Department of Justice report that says that there are about 115 “stereotypical” child kidnappings in the U.S. each year and that teenagers are most at risk. We parents of young kids think that our children are the most precious things in the world, but it seems that, at least statistically, few other adults want them. There were about 72 million children in the U.S. during the 1999 year that the Feds made their survey. So a child has a 1 in 626,000 chance of being kidnapped in any given year and most of those are teenagers who are left unattended for at least 2-3 hours per day. If we take a one hour/day figure (averaging in young children, who are seldom unattended for long), that’s 26 billion unattended-child-hours nationwide during which 115 kidnappings occur (assume that no kidnappings occur when a child is watched by an adult). That’s approximately one kidnapping every 228 million hours or one every 26,000 years of continuous time left alone.

I can’t think of a good way to get a more precise number for toddlers. The government says that they are much less likely to be kidnapped than teenagers, but on the other hand toddlers are also typically fairly closely monitored by an adult (at least looking through a kitchen window into a backyard).

Anybody find an error in the above calculations? And what do we do with the result? Will knowing the statistics make it less likely that we will panic when a child falls momentarily out of sight? Can we follow our heads or must we be slaves to our (jumpy) hearts?

My friend Avni, who works tirelessly and without pay on behalf of Kids on Computers (http://www.kidsoncomputers.org), a 501(c)(3) non-profit, asked me if I had any more laptops to donate to her organization. If you’ve been dreaming of upgrading to Windows 8, this is your big chance/excuse. [Sadly, the children who get these machines will not be able to enjoy using Windows 8; the machines are wiped and installed with Linux.]

Here’s what Avni says…

Kids on Computers is seeking laptops for an elementary school in Molcaxac, Puebla, Mexico. The laptops must have 512MB RAM, include a power adaptor and be in working condition. We’d like to have the laptops by July 14th as we have a group of students from Mexico visiting the US leaving to go back at that time and they can transport them back.

I’m listening to Nudge: Improving Decisions About Health, Wealth, and Happiness in my car. The authors describe a survey of MBA students in which just 5 percent predicted that they would turn out to be in the bottom 50 percent of the class. Fifty percent of the students predicted that they would fall into the top 20 percent when the semester was over. How about their professors? A university-wide survey (not just the B-school) found that 94 percent of professors imagined themselves to be above average in competence.

[I wonder if the more elite the group the greater the overconfidence. A math professor told me about her days as a graduate student teaching calculus at Florida State: “A third of the students were jocks who didn’t do any homework. They expected not to learn anything and to fail the class, which they did.” She was fortunate to land a job as an assistant professor at an expensive elite private university. “It was the same situation there. About a third of the students didn’t do any work and didn’t learn any calculus so I gave them Fs, just like at Florida State. A few days later every dean at the university converged on my office to explain that my students were not failures and could not possibly receive Fs. I had to change all of the grades to Cs.”]

A friend of mine is in the mathematics department at a large state university. I asked him what he was going to teach for the upcoming semester and he replied “I told the head of my department that I would teach anything except our classes for education majors.” What’s wrong with those classes? “Remember that the weakest students at the university are the ones who are going to become teachers. The curriculum of the ed school is not about content, so the students aren’t expected to learn any math. The ed school tries to lower the bar as much as possible so that they can crank out as many teachers are possible.” What does the ed school want their majors to learn about math then? “They want us to teach them how to draw a vertical line on the blackboard, how to develop a lesson plan. We’re always having fights with the ed school professors because we try to put some math into a course with a title such as ‘Math for Elementary School Teachers.’ I tried teaching the class once but it was a disaster. The textbook is almost content-free. You’re trying to teach Euclidean geometry without mentioning anything about proofs.”

Friends have been asking me how it is possible that the Asiana 777 landed short of the runway at SFO.

It turns out that the instrument landing system (ILS) glide slope was out of service. So the pilots were likely conducting a “visual approach”, i.e., looking out the window to see if the airplane was properly positioned to land. There are synthetic glide slopes available from WAAS-enhanced GPS receivers and there is a RNAV 28L approach at SFO that provides LPV minimums for such units. These cost about $500 to install in an experimental (uncertified) airplane, but regulation adds $10,000 to that cost when the gear goes into a certified airplane such as a four-seat Cirrus SR20. Touching even one screw on an airliner, after it leaves the factory, costs closer to $1 million. So it seems unlikely that Asiana had retrofitted their B777 with the latest WAAS GPS gear.

How hard it is to fly a visual approach? That’s how all approaches are flown in light piston-powered airplanes during training. Things move both a little faster with jets and a little slower. The speeds are faster, e.g., 120-145 knots on final approach instead of 60-70. What is slower is the response of the aircraft to power adjustments. Some of this is due to simple inertia. The airliner weighs a lot more. Some of this is due to the fact that jet engines, once “spooled down”, can’t provide instant power.

Here’s a story from my second month of flying regional jets for Comair, a Delta Airlines subsidiary. I am leaving the original language but adding notes in brackets because this was written for my pilot friends.

Today was a beautiful clear and calm day for flying. I took the CRJ [Canadair Regional Jet, a 50-passenger 53,000 lb. airliner] from RDU up to LaGuardia. The ATIS [canned weather broadcast, updated hourly] said that we could expect the ILS 22 at LGA. Our clearance was to descend and maintain 4000′, head for the Verrazano Bridge, then fly up the Hudson River. We were high and close to the airport, restricted to a minimum speed of 180 knots, when New York Approach cleared us for the “visual 22”. These are the toughest maneuvers for newbies because one has much less time to get stabilized than with a full ILS procedure and it is almost impossible to use the autopilot, which won’t intercept the radio beams at extreme angles.

The airline encourages us to fly 5 knots faster than “Vref” [around 145 knots in a CRJ with all seats filled] during training, in order to have a margin for error in case of wind gusts or incompetence. When a runway is short, however, the extra energy is difficult to dissipate and tends to result in significant float. The runway at LGA is 7000′. A test pilot demonstrated the ability to get the airplane stopped in about 3000′, but it wouldn’t necessarily have been consistent and it certainly would not have been comfortable for passengers. The minimum runway length that people regularly use for the CRJ is 6000′.

My approach was slightly fast and slightly high. I was reluctant to adjust the thrust in the last 300′ or so because we had been fairly stable on glide slope and on airspeed. In previous approaches I had tended to overcontrol. I started the round-out at the 1000′ markers, and touched down about 2500′ down the runway, applying moderate brakes and thrust reversers and turning off at Charlie, having chewed up almost 5000′ of runway (out of 7000′). Passengers complimented me on the smoothness of the landing, saying “It is usually rough here at LaGuardia” (of course it is usually rough because pilots more skilled than I are trying to get the plane on the ground, have the spoilers deploy, and stop the plane before it runs into a swamp).

Captain Mark said “That landing sucked. I’ve got 13,000 hours in this airplane. I’m going to show you how it is done on the next leg.” He then asked “Are you flying the airplane or is the airplane flying you?” When I asked for specific tips Captain Mark replied that I was an instructor and ought to be able to figure out what I was doing wrong. He grudgingly confirmed that I had left too much thrust in for too long.

We approached Charlotte, North Carolina in near perfect conditions. The weather was smooth and, due to some clouds at 2500′, we were given vectors for the full ILS 23 approach. [The controllers vectored us so that we were lined up with the runway approximately 10 miles from touchdown.] Captain Mark let the autopilot do most of the work, concentrating on getting the thrust exactly right for a stabilized approach. At about 200′ above the ground, Captain Mark disconnected the autopilot and transitioned to hand-flying. Somehow he ended up a little fast and also flared a bit too high. The CRJ is a very efficient glider and spooled down jet engines don’t supply the kind of drag that props would. The CRJ entered a shockingly efficient glide in ground effect at 10-15′ above the runway. We weren’t descending. We weren’t slowing down. The 7500′ runway was slipping away beneath us.

It is unclear how one would fix a situation like this. [In a piston airplane the best and easiest fix is to add power, retract the flaps, and climb away from the runway in order to try again; this can’t be done in an airliner due to the long spool-up time of the engines.] In a piston airplane you’d add a touch of power and pull back for a slower and less efficient airspeed. The airplane would sink due to loss of efficiency and the power would slow the vertical speed. In the jet, once the thrust levers are back it takes 3 or more seconds to get any significant power from the engine. Nosing the airplane forward would result in hitting the nose gear, which isn’t any better on a jet than on a piston four-seater.

After we had sailed over approximately half the runway, the airplane finally started to settle towards the surface. We touched with about 3000′ remaining [i.e., 4500′ down the runway, 2000′ more float than I experienced at LGA]. Captain Mark slammed hard on the brakes, to the point where the passengers probably would have said “ouch!”, and applied full reverse thrust. Tower called and asked “Are you going to be able to make Foxtrot?” This was the second-to-last taxiway and only about 500′ from the end of the runway. In fact, we did make Foxtrot, but only barely. We used just about a full 7000′ of runway. [I.e., at LGA we would have been nose-to-nose with the boats.]

What did I learn from watching a very capable guy with 13,000 hours of CRJ experience? That landing a CRJ consistently requires more than 13,000 hours of experience…

————— end of story from 2008

Additional background: The CRJ is an adapted business jet and, lacking leading edge devices or “slats”, lands much faster than a standard airliner such as a Boeing 737. In addition to the challenge of speed the pilot must, in the last 40-50 vertical feet of the flight, pull the airplane from its 3-degrees nose-down attitude to a standard nose-up landing attitude of about +9 degrees. (This lead one FlightSafety instructor to refer to every landing in a CRJ as a “controlled crash”. The procedure is different enough than in a Boeing or Airbus that the plane comes with a special briefing card for jump-seating pilots of conventional airliners so that they don’t start screaming in the last 30 seconds of the flight.)

Follow-up: Folks to whom I emailed the story asked me how the rest of the trip with this pilot went. My reply: “Captain Mark found fault with everything that I did for the next three days. I hadn’t ironed my shirts properly. I left my bags next to the airstair door while doing a preflight inspection, thinking that it would give the captain and flight attendant more space and freedom to put away their bags. Captain Mark admonished me “You have to go up into the airplane, put your stuff away, and then go back outside to do the preflight.”

Punchline: About six months later, US Airways 1549 was flying the same route (LGA to CLT) and went down in the Hudson River. Asked my opinion about the heroes Captain Sully and Jeffrey Skiles I said “Hey, Captain Mark and I took 50 passengers from LGA to CLT. We got them to the gate at Charlotte, on time, warm and dry, and nobody called us heroes.”

Here’s a simple-minded geophysics question, appropriate for the 95-degree heat that we’re experiencing in Boston right now: Why are underground parking garages hot?

At a friend’s house and they don’t have air conditioning? Go to the basement where it will be cool.

Have a collection of fine wine from Costco that you want to keep cool? Dig a cave and park the bottles there so that they will stay at a constant temperature somewhere near the average temperature at the surface of the Earth (pilots are taught about the standard atmosphere that is 15C at the surface, about 59 Fahrenheit).

Go into a parking garage underneath an office tower or apartment block and it will be hot and stuffy, oftentimes even hotter than the surface shade temperature. How is this possible?

Here are some possible explanations, but I can’t figure out which, if any, is correct.

• The parking garage is mostly air, which has low thermal mass, with relatively small patches of contact with the cool adjacent (high thermal mass) ground. The air-to-ground-contact ratio is much higher in a parking garage than in a natural cave or a purpose-built wine cave.
• Much of the thermal mass in the garage consists of cars, which have recently driven in from the hot surface and are therefore hot.
• The parking garage has high capacity exhaust fans so that people don’t die from CO poisoning. Therefore hot air is being sucked into the cave to replace the dirty air that is blown out.
• The parking garage has some doors that are typically open to the surface (this one does not seem significant to me since hot air rises).
• The cars generate a lot of waste heat as they drive around within the garage.

What do folks think? Why isn’t going down into an urban parking garage a pleasantly cool experience, like going into a natural cave?

If you’re looking for some beach reading on July 4, I recommend Bunker Hill: A City, a Siege, a Revolution, by one of our most readable historians, Nathaniel Philbrick. I’m still working on the background section, but it is interesting to see how Massachusetts political sentiments have changed in the past couple of centuries and also how the professional historian’s view differs from what we learned in K-12 American history.

Here are some quotes from the book:

For most of the early eighteenth century the American colonies had enjoyed the benefits of a policy later known as “salutary neglect.” Left to do pretty much as they pleased, the colonies had been free to pursue economic growth unhindered by the onerous taxes paid by most British subjects. But by the end of the French and Indian War in 1763—a war fought, in large part, on the colonies’ behalf that had saddled Great Britain with a debt of about $22.4 billion in today’s U.S. currency—the ministry determined that it was time the colonies began to help pay for their imperial support.

Rather than propose a means of raising revenue that they deemed fair, the colonials were more than happy to direct their considerable energies toward opposing whatever plan the British ministry put forward.

The British ministry had a problem. The crown-chartered East India Company was burdened with too much tea. To eliminate that surplus, it was decided to offer the tea to the American colonies at the drastically reduced price of two shillings per pound—a third less than the original price. Unfortunately and unwisely, Parliament included in the reduced price a tiny tax of three pence per pound. This gave the patriots ideological grounds on which to object to an act that might otherwise have been viewed as a windfall for the colonial consumer.

Other, less noble reasons motivated the patriots. Many Boston merchants sold illegal Dutch tea procured from the Caribbean island of St. Eustatius (known today simply as Statia). Since the low-priced East India tea would undersell the smuggled Dutch tea, the merchants stood to lose significant income.

Boston’s most widely known poet was a twenty-one-year-old African enslaved woman named Phillis Wheatley, … She’d also used that fame to leverage a promise from her master, Daniel Wheatley, to grant her freedom. For the citizens of Boston, whose love of liberty did not prevent one in five families from owning slaves, … [she wrote] “How well the cry for liberty, and the reverse disposition for the exercise of oppressive power over others agree I humbly think it does not require the penetration of a philosopher to determine.”

Gage [a British official] left the king with the impression that he was ready “at a day’s notice” to return to America and implement whatever “coercive measures” were required. In actuality, he had deep reservations about returning to the colonies, particularly when it came to Massachusetts. “America is a mere bully,” he’d written back in 1770, “from one end to the other, and the Bostonians by far the greatest bullies.”

Boston was known for its love of liberty, its piety, and its prostitutes. In the town’s hilly northwestern corner was a lightly settled neighborhood that the soldiers dubbed Mount Whoredom. One afternoon at the end of July at an establishment known as “Miss Erskine’s,” fifteen British officers “committed,” John Andrews wrote, “all manner of enormous indecencies by exposing their anteriors, as well as their posteriors, at the open windows and doors, to the full view of the people . .

Instead of the selfless patriots we were taught about, Philbrick finds tax-dodging slave-owning patrons of prostitutes.

Separately, taxing the middle class to fund public works stimulus projects is apparently not a new idea:

The Bostonians had objected to paying a tax on British tea, but they were more than willing to fund an expensive public works project if it helped the town get through the crisis [the British Navy sealing off Boston Harbor]. Under the direction of the town’s selectmen, municipal funds were used to hire jobless mechanics, artisans, and dockworkers to build ships, clean up the wharves, and repair roads. John Andrews complained that while the poor had the town to relieve them and the rich had their savings and rents, small merchants such as himself had nothing. “[The] burden falls heaviest, if not entirely, upon the middle people among us,” he wrote.

If you liked In the Heart of the Sea: The Tragedy of the Whaleship Essex (highly recommended!) you’ll probably like this book.

Happy 4th of July to all readers!

I recently listened to some Ray Bradbury stories in my car. Nearly all were written in the 1950s and set in the 21st Century. Yesterday, the Supreme Court issued a couple of rulings in support of gay marriage. It occurred to me how differently the future turned out from what Bradbury had imagined.

Bradbury’s stories feature working husbands, stay-at-home wives, and two respectful children who call their father “Sir”. The stories that I listened to did not include any single parents, gay people, gay couples, or heterosexual couples in which the woman was the primary earner.

What else did Bradbury get wrong? Telecommunications in 2050 looked just like telecommunications in 1950. Each house, home to a family of husband, wife, and two children, had a single wired telephone. It would ring and, as there was no caller ID, the call would begin with the person who answered asking who was calling and to whom the caller wished to speak.

Bradbury imagined a static future Earth population with roughly 2 billion people. If anything, the population would be on its way down due to nuclear wars. Those people would invest heavily in talk psychotherapy, which would reliably make them feel better about everything. Nobody in Bradbury’s stories takes mood-improving pills; if they are suffering from anxiety, a chat with a psychologist will put them right.

Bradbury’s workers of the future seemed to enjoy their jobs (unlike the 70 percent of Americans who are “not engaged” or “actively disengaged” according to this Gallup poll). Nobody in Bradbury’s stories is collecting welfare, unemployment, disability, or any other kind of taxpayer-funded payments unrelated to work. Other than soldiers and policemen (all men in both cases!), nobody seems to work for the government.

Folks:

East Coast Aero Club has acquired a new 2012 Super Decathlon aerobatic training airplane. Whenever the school gets a new plane I try to learn how to fly it. Currently I don’t have even a tailwheel endorsement and I tend to get motion sickness from extreme maneuvers if someone else is on the controls. So this will be a personal challenge and I’m wondering if readers who have Decathlon/aerobatic experience have any suggestions.

My current plan is to spend roughly 5 hours learning the airplane, maybe with the occasional aileron roll when bored with pattern work. This would include slow flight, commercial maneuvers such as chandelles and lazy-8s, short field landings, etc. Then try to spend another 5 hours doing some basic aerobatics. What are the best maneuvers for someone who hasn’t yet built up a good tolerance for motion/Gs? Any special tips regarding the Super Decathlon?

Thanks in advance.

[Separately, the club has a very experienced instructor who is a former U.S. Air Force jet fighter pilot, but he is not available every day so the school has posted a help wanted ad for an aerobatics instructor. If you know of someone good who is interested in living in the Boston area, please tell them about this job.]