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 Interfaces that Continue to Kill
 Re: Traffic Engineers
 Re: CDs and Tubes and Stuff
 Little Browser Bumpers
 Slow PowerPCs
 Time for Mouse Advances

Interfaces that Continue to Kill

Your article on John Denver [Interfaces that Kill] is fascinating and you may be interested in the American Airlines Cali crash some years back that killed a *lot* more people. In this case the UI of the automated flight management system seems to have been largely responsible (see coupled with dumb software design that caused the plane to circle *back* to a waypoint it had already passed, without warning the pilot that in essence this was a very odd thing to want to do.

The interesting thing about this incident is that the conclusions reached tend to blame the pilots but if you read the report you can see that the UI design of the flight management system really screwed them up and probably killed them (not to mention the unfortunate passengers). In essence, they wanted to go to waypoint ‘ROZO’ but the flight management system had been designed with the idea that waypoints should be selected by the first letter of the waypoint, which would bring up the most popular waypoints first, in this case ROMEO, a waypoint several hundred miles away. It didn’t occur to the designers that proximity to a waypoint might be a more important factor, i.e list them in ascending distance from the aircraft’s current position. Anyway, read the report, it is a very interesting story about the interaction between man and computer.

I think the topic ‘When Interfaces Kill’ is a very fruitful one to pursue because the stories (and for sure you can find a whole lot more out there) are compelling lessons to designers. After all, a user losing a document is one thing but 200 people being mulched in a plane crash does kinda carry more weight. Why not make this topic an ongoing column for a while - I think it will be very popular.

I'm quite familiar with the Cali crash and was moved enough by what had happened to invent a mapping system that should eliminate the possibility of such confusion (US patent 6,076,042). The instrumentation in aircraft today remains remarkably crude. It is testiment to the skill of both pilots and air traffice controllers that safety remains so high.

"Traffic Engineers: Now I know I’m a Designer"

I graduated from UCLA design last year. After I read your story “Traffic Engineers: Thieves of Time” I realized that maybe I am cut out to be an interface designer.

I agree exactly except you missed seven more that totally suck:

  1. Build islands of asphalt that block turning into cross streets, or getting on from cross streets, and which additionally have left turn lanes way to short to absorb the left turning traffic and overflow, blocking through traffic. Waste miles of pavement by making it totally unusable and completely ugly.
  2. Build freeways, which by definition are free from stoplights. Then put stoplights on onramps which cause traffic to enter 75mile/hour traffic at 25miles/hour. Ostensibly the lights smooth the flow of traffic but in reality if you have 1,000,000 cars per hour entering the freeway without the lights you still have 1,000, 000 cars entering the freeways per hour and 30 seconds. Take this idiocy further and put stoplights at freeway intersections.
  3. Never, ever fix confusing traffic signs on the freeway. There are two near my residence in downtown LA that cause traffic tie-ups every day and have been for 30 years. One freeway (Interstate 10) disappears at the junction where it meets Interstate 5 inexplicably and invisibly turning itself into the 60 freeway. It turns up again 5 miles to the north with no seeming relationship to its other part. Motorists unaware of the mule trail origins of area roads have no idea what is happening and usually slow to 5MPH in the fast lane trying to figure out which lane they should be in. The sign warns them about 50 feet from the split giving them about 1/2 second to cross 3freeway lanes.
  4. Design freeway entrances and exits that overlap, extend for miles and provide easy but Illegal passing lanes for immoral bullies. Instruct police and highway patrol to ignore violators and even violate the law themselves if they feel like it. This causes “accordion” effect as violators from the rear speed by and butt in front of polite people.
  5. 90% of accidents happen in the slow lanes tailgating. 10% of accidents happen in fast lanes speeding.10% of tickets go to motorists in slow lanes. 90% of tickets go to motorists in fast lanes. In addition the tailgaters will not let people change lanes which causes timid drivers to slow down as they futily try to find a driver willing to let them in. Yeah, the cops are doing a good job.
  6. Make giant trucks drive in slow lanes with tailgaters, old people, merging traffic and speeders who think (correctly unfortunately) that speeding in the slow lane fools cops. These same speeders like to pass the trucks, at high speeds, on the right (the trucks blind spot). Then blame the truckers when they are involved in accidents.
  7. In order to curb population growth stop repairing and building roads. Yeah that’ll work!



Re: CDs and tubes and stuff

Before I got into web land fully I worked in audio, so I wanted to pass on my two cents on some of the things you wrote about things aural [in A Century of Scams, Dec, 1999]. So you can put me in the “nut” camp right away be it known that I have tube equipment (Audio Research which IMHO makes far better tube gear than McIntosh) and a large collection of vinyl records which I still enjoy.

Won’t say much about tubes vs. solid state amplification except to say that modern tube and solid state amps can sound amazingly similar. A good designer can tune their amp to sound neutral or tube-like be it tube based or solid state. I made my decision for tubes based on how they sounded with my speakers. Unfortunately amplifier specifications are a poor way to choose an amplifier if you own a speaker that represents a difficult load to the amplifier as I do. When friends ask me what kind of gear to buy I steer them to solid state gear because most people have little interest in maintaining their audio gear-- something tube gear requires you to do.

Some vinyl sounds better than the equivalent CD, but my experience suggests that most of the difference is in how the records are mastered. It is sad in a way that good home hi-fi gear can reveal how poor the quality of most records really are. And that isn’t going to change no matter what the format, be it LP, CD, SACD, or DVD-A.

I have heard quite a few DVD based stereo recording mastered in a 24 bit, 96Khz format. These sound universally better than their CD or LP equivalents. I suspect that a large part of that is the dynamic range issue you mentioned in your reply to a previous email. However I do not see a lot of market success for either of the 24 bit formats proposed. SACD, the Sony format, has been out for at least a year with minimal software support. In addition the players are very expensive. I’d love to have a SACD player, but am unwilling to pay $1000 plus. DVD-A was supposed to be out a year ago. Players are just now starting to appear but there is no software due to problems with the watermark copy protection. On top of that the market has little interest in $25+ software when the feeling is that CD is perfectly adequate sound quality. A whole lot of people seem happy with MP3, a format that to me sounds dead and lifeless (I call it undead music).

I do not share your feelings about surround sound (which even in its 5.1 configuration is very different than the old quad format). My reservation is that most folks do not set up their stereo speakers properly. The chance that people who are unwilling to devote space for two speakers will be willing to give up the correct space for the 6 speakers required for 5.1 seems slim to me. If you are fortunate enough to have a dedicated home theater or music room that is a different story. But I’m a big music and movie fan and I can’t spare a room solely for music and home theater. Blame that on the fact that I’m in the Bay Area where you almost have to have hit it big in an IPO just to buy a 2 bedroom condo!

Finally, the move to multi-channel surround for music is going to be a bit bumpy on the mastering side. There are some conventions about stereo records that everyone has settled on. Lead vocal in the center for example. But the early surround music records I’ve heard have a tendency to do some bizarre things. Instruments come from all directions which I find disturbing. When I go to a concert all the music is in front of me. I find it hard to pretend I’m sitting in the middle of the band. When surround is done well, using the rears for what is mostly atmosphere and hall noise the result is indeed amazing. I’m just afraid that the wonderful theory will in practice sound more like all those ping-pong stereo records from the early days of stereo.

Chris Daley

Chris, Chris, Chris, you are sadly behind the power curve. Nobody’s talking 5.1 anymore. Haven’t been for almost three months. It’s 7.1 now! Three speakers in front, two on the sides, and another two in back, plus the subwoofer(s). Thank heavens I have the world’s most understanding wife, since our living room looks like a recording studio.

The 5.1 and 7.1 surrounds are quite different from Quad, because Quad really sucked. it had only around 3dB separation between all but the two front channels. That’s like nothing. The mixes tended to be as bizarre as some of the surround recordings out now. (I have a new Eagles live concert DTS recording in 5.1 surround. Apparently a pair of drummers sneaked into the audience, armed with their full drum sets, ‘cause they’re out there banging away in the surround channels.) On the other hand, some of the better surround recordings are downright eerie in their realism, something that could never be said for Quad.

I agree with you that most of the problems with recordings can be traced back to bad mastering, and that records often had more careful mastering than CDs have had. On the other hand, I bought no record during the last five years I was collecting that didn’t have serious defects—clicks and pops—on first playing, and it was, of course, downhill after that. It makes you wonder, given that software situation, what could possibly make a new turntable, for example, be worth $75,000. No, that’s not a misprint. One of the audio magazines given to extolling the virtues of $900 connection cables and other patently obvious rip-offs claims they could hear a wonderous new sound from this recently-released turntable, a sound simply not realizable with an inexpensive table (the inexpensive turntable they referenced cost only $6,500.)

The manufacturers of the new format digital audio disk players are way overcharging people to gain back a little R&D money. If either format proves successful, the prices should drop to a couple hundred dollars for a player. As for the software, if an SACD costs any more than a few pennies more than a standard CD, they are gouging, too. Since SACD has provisions for a standard “redbook” CD layer, these disks can be made 100% backward compatible. If Sony had a brain in their avaricious little heads, they would sell every CD in their collection with SACD hidden inside, at no premium in price. (DVD-A, the competing standard is not backward compatible.)

Tubes are wonderful. I even just bought a little “great American five” tube radio kit just so I could enjoy those thrilling days of yesteryear, burnt fingers and all. However, I’ll put my 5500 watts of McIntosh solid state amplification up against anybody’s tube rig anytime. If you don’t have to replane all the doors in the house after watching Earthquake, you just didn’t experience it.

Not that I'm immune to the siren song of the tube amplifiers. I almost bought one of the new $15,000 Mac tube amps this year after discovering it was just about to sell on ebay for the low, low price of around $9000. Fortunately, a Google websearch brought up a careful argument as to why that would be a really bad idea. I had to listen. After all, I'd written it.

Does anyone know where there is a good ebay anonymous meeting?


P. S., even though McIntosh, the audio company, has no “a” in their name, Apple still had to pay them a fortune to use the name.

Little Browser Bumpers

After reading your articles about Fitt’s law, I did some hacking on the mouse behaviors in Windows. Some neat navigation for IE, and some improvements to the Windows taskbar:

I’d like to hear your comments -- this stuff isn’t perfect yet, but I think the direction is an interesting one.


I think it is an excellent direction. This is exactly the kind of thinking that has been missing from HCI design lately.


Slow PowerPCs

While it is true that the g4 chips are somewhat faster than their x86 counterparts, they are nowhere near twice as fast. On average the 500 Mhz G4 is probably equivalent to a 700 Mhz P3 or a 650 Athlon. There are any number of reasonable benchmarks available on the web which bear this out, as long as you don’t look at only a few photoshop filters that Jobs likes to parade about.

The performance gap (not just perceived) is a real problem for Apple. AMD has already stated they intend to be up to 1.4-1.5 Ghz in the first half of 2001. The problem is that Motorola has no interest in keeping up.


Conventional Wisdom held that that PowerPC architecture would ensure that Motorola/IBM led the power curve in microprocessors. What has happened is testament to the power of human ambition. Intel is eating Motorla's/IBM's lunch and the latter two companies are offering them Ketchup.

Time for Mouse Advances

I was reading the article “Eek! A Two-Button Mac Mouse?”, and saw your comment about the two-button mouse being overdue.

Given your insight into computer/human interfaces, I wanted to ask you of your opinion of an alternate arrangement of mouse controls or system/software implementation of similar functionality.

In almost twenty years of computer use, any multiple-mouse button that I’ve owned or tried indeed offered more versatility -- but inevitably, some odd hand contortions are required to operate them. Most notable is the scroll wheel, which I would say is the most convenient device on today’s mice (given how much actual reading done on a computer these days, thanks to e-mail and the World Wide Web), yet the wheel is a somewhat clumsy way to solve the problem.

I would like to see a switch of some sort that would temporarily switch the focus of mouse movements to scrolling instead of cursor movement. After all, the mouse itself is designed for precise, rapid and comfortable movement of a pointer -- why not employ it for different kinds of repetitive actions?

The switch could be a thumb button or a press upon the whole mouse similar to the full-mouse button on Apple’s optical mouse. Or, the switch could be incorporated into software (a key combination, an on-screen button, a “kick” into a screen corner or area, etc.)

People love pushing buttons. However, it seems to me that the push for a more complex mouse pays too much attention to hardware design, instead of focusing on the problem of input itself, and better software design.

Apple has a history of implementing powerful innovations in computer use (such as file sharing over IP, system-wide drag-and-drop, or QuickTime) as merely subtle extensions of basic computer use, rather than requiring separate software or dialogs for use. In this regard, I feel that interface elegance still stands as the purpose behind the slogan “the computer for the rest of us”.

I hope that Apple would carefully re-think the mouse before following what virtually all other computer companies have decided to produce -- I think that there’s still a better solution to be discovered.

Curious to know your opinion,

Richard Cote
Sideways Graphics & Design

Thanks for a thoughtful letter. Two button mice are a decade overdue on the Macintosh. The scroll wheel is an important addition, however, Richard, you have it right. We can and should do more. Not only is it time for a clear advancement in pointer functionality, it is time for better and more efficient two-handed input.

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