The usability of everyday things

I’m taking a class on “Web Usability”, and our first assigned reading is The Design of Everyday Things by Don Norman. This is a very readable tour through design principles that can help us create devices and systems that are easy and even enjoyable to use.

The book is peppered with interesting examples of bizarre or cryptic designs. Norman seems particularly fond of talking about light switches (such a simple device, and yet so many are hard to use!). As a pilot, I also enjoyed the frequent examples he cited from the world of aviation, where a bad interface can mean the difference between life and death. However, he also says that his personal rule is to avoid criticizing unless he has a solution to offer. Now there’s a high bar!

Norman identifies “discoverability” (can you figure out what actions are possible?) and “understanding” (do you know what the controls/displays mean?) as key components of good design. He also emphasizes the importance of a user having a good “conceptual model” of the device – even if that model is inaccurate in a technical sense. A successful model is one that allows the user to operate the device successfully.

I also found his discussion of the balance between “knowledge in the head” (memory and learned skills) versus “knowledge in the world” (objects, signs, instructions) to be thought-provoking. It makes sense to try to strike a good balance between how much advance training/prep the user needs versus how much they’ll have to read/learn/absorb while using the device. Going too far in either direction makes things harder to operate.

One of the biggest takeaways for me was his encouragement to remove the concept of “error” from an interface. He points out that when we don’t understand something another human says, we don’t say “You made a speaking error.” Instead, we interact and try to figure out what meaning was intended. Similarly, devices (and computer programs) could shift from “error” feedback to help or guidance that aids the user in specifying their intent in the form that is needed. He suggests that we think of a user action as an approximation to what is desired, and help the user to improve it. Great idea!

Chapter 5 is devoted to an analysis of errors: different types, different causes, and different remedies. I like the suggestion to treat errors as learning opportunities (for the user and for the designer); we can brainstorm ways that the error could be entirely precluded in the future. I will be on the lookout for ways to apply this in my ongoing flight training.

Some quotes I enjoyed or found insightful:

  • “Machines require us to be precise and accurate, things we are not very good at.”
  • “We have to accept human behavior the way it is, not the way we wish it to be.”
  • “We use logic and reason after the fact, to justify our decisions to ourselves (to our conscious minds) and to others.”
  • “How can the designer put knowledge in the device itself?”
  • “Expert [users] minimize the need for conscious reasoning.”

Flying to Rarotonga

The Rarotonga International Airport (RAR) has a runway that is 7,638 feet long.

I am flew there on a 777-200. That seems like a rather short runway for a big jet. I’ve landed on longer runways myself (like San Bernardino or Ontario). Curious, I looked up the minimum runway length for a 777-200. According to the Air Cyber Alliance, it is 8,563 feet. Yes, that is longer than the Rarontonga runway. Eeek?

Minimum runway lengths are dictated by how much space the plane needs to take off (which is generally longer than the space needed to land. Yes, this means planes can land somewhere and then be unable to take off again). The minimums are calculated for the aircraft when fully loaded, at max gross weight. So one way to take off in less distance is to reduce the load – fewer passengers, less cargo, or less fuel.

According to the seat map, my return flight is nearly or completely full of passengers, so they won’t go that route. And they can’t skimp much on fuel: the flight from RAR to LAX is quite long (4,688 miles, 10 hours) and the 777-200 has a maximum range of 5,240 miles when fully fueled. Plus, you don’t just take exactly enough fuel to get there; you need extra fuel in case you have to divert or circle or otherwise go out of your way. So maybe they just reduce cargo?

I noticed that they schedule return flights to depart close to local midnight – probably trying to use the coolest part of the day to improve the plane’s performance. And by “coolest”, I mean 78 F. Challenging for flying. I want to chat with these pilots!

How strong is that sunshine?

I am heading to the Cook Islands in a few weeks to explore the island of Rarotonga. This is a tiny island, covering 26 square miles and with a population of 10,000, in the south Pacific.

To prepare for the trip, I have been monitoring the weather out there. This is their rainy season, so it’s getting pounded with thunderstorms (eek!). I’m hoping it will clear up a bit before my trip.

In addition to thunderstorms, I noticed the weather report on the UV index, which has been varying from 7 to 9 during the day. At first I thought maybe the max value was 10, but then saw it go up to 11. So I looked up what exactly the UV index is. I learned that it doesn’t have a max value! It’s a measurement of the amount of “sunburn-producing UV radiation”, so it focuses on the amount of radiation in the 295-325 nm range. It is unitless, and the range is linear (so a UV index of 10 is twice as strong as 5). It was originally designed so that 10 would correspond to typical noontime summer (max) sunlight. However, this was established in 1992, and since then, higher and higher values have been observed, up to the world record of 43 (!!!) in 2003, although that value is contested and might “only” be 26.

Wikipedia’s guidelines suggest that one should limit midday exposure if the UV index is anywhere over 3, and over 6 yields “high risk of harm from unprotected sun exposure.” If it gets over 11, “unprotected skin and eyes can burn in minutes.” So, time to break out the sunscreen and protective clothing… unless I’m stuck indoors due to thunderstorms :)

U.S. concentration camps in WWII

Did you know that the U.S. had its own concentration camps during WWII? Every time I re-encounter this fact, I am amazed anew. After the Japanese bombed Pearl Harbor, President Franklin D. Roosevelt signed an executive order and 110,000 Japanese Americans were rounded up and placed in camps in the western U.S. By the way, almost half of the 68 civilian casualties at Pearl Harbor were Japanese Americans. (A total of 2,403 Americans died that day.)

In the 1980s, an investigation determined that the decision to put Japanese Americans in camps had little grounding in any evidence of disloyalty and was instead due to “race prejudice, war hysteria, and a failure of political leadership” (Senate Bill 1009, 1987). This led to President Reagan signing the Civil Liberties Act in 1988 that apologized and authorized reparations for camp survivors.

Today’s debates about immigration, deportation, and refugees are held in the context of constant background fear about terrorism. Our history shows us that our country, just like any other, can be moved to acts we later regret out of fear and concerns about national security. We can claim no inherent moral superiority.

In addition to knowing facts, like how many people were groundlessly incarcerated, it is helpful to hear about individual experiences. The Densho digital archive collects stories of Japanese Americans with a particular focus on their incarceration in American concentration camps in WWII. Densho provides more than 900 video interviews as well as photos, documents, and camp newspapers. The photo at right is of the Manzanar concentration camp in California, taken by Ansel Adams.

The interviews talk about how people were rounded up, life in the camps, and the impact of that experience. As just one example, Aiko Herzig-Yoshinaga talked about giving birth to her daughter while living in a camp. She was unable to persuade the camp to provide canned milk for her daughter, who was allergic to powdered milk. Yet some internees had access to art classes, or softball games as shown at left (I love this picture).

One detail of personal interest I learned is that one of the Citizen Isolation Centers (where “so-called troublemakers” were sent from the concentration camps) was located near my hometown of Moab, Utah.

These interviews are fascinating and educational. I look forward to listening to more of them. Perhaps the stories shared in this collection can help us to avoid repeating our mistakes.

Cornelia Fort and WWII

On December 7, 1941, Cornelia Fort was up on the air giving a flying lesson near Pearl Harbor when the Japanese bombed it. “I jerked the controls away from my student and jammed the throttle wide open to pull above the oncoming plane,” she wrote.

“The painted red balls on the tops of the wings shone brightly in the sun. I looked again with complete and utter disbelief. Honolulu was familiar with the emblem of the Rising Sun on passenger ships but not on airplanes.

I looked quickly at Pearl Harbor and my spine tingled when I saw billowing black smoke. Still I thought hollowly it might be some kind of coincidence or maneuvers, it might be, it must be. For surely, dear God…”

She quickly landed her plane and ran for shelter with her student while Japanese fighters strafed the area. She was 22 years old.

Cornelia survived the attack. Other civilian pilots were not as lucky. She returned to the mainland and joined the Women’s Auxiliary Ferrying Squadron, a precursor to the WASP program.

“We have no hopes of replacing men pilots. But we can each release a man to combat, to faster ships, to overseas work. Delivering a trainer to Texas may be as important as delivering a bomber to Africa if you take the long view.”

Tragically, she died just two years later (age 24) in a mid-air collision with another ferry pilot. She was an excellent pilot and no doubt would have gone on to do other great things. How I wish I could have known her!

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