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AskTog Interaction Design Section Anatomy of a Panic: A Case Study
AskTog, October 2004
Anatomy of a Panic: A Case Study
Last month, I talked about The Worst Interface Ever, involving an after-market pump and switch for the Lexus RX-300, designed by and for engineers. The switch is not only located at a random and undocumented location and position, hidden in the engine compartment, but must be switched accurately every time the car is connected to or removed from the RV towing it. A single error carries a price tag of $5000.
Mr. Brown, as I shall call him, had his pump and switch installed on his RX-300 in September, 1993. He was, to put it mildly, shocked when the installer showed him this tiny mechanical switch along a cross bar leading to the radiator and explained what he had to do with it and what would happen if he failed to do so. Nonetheless, with $1500 already invested in this project, he wasn’t about to spend another few hundred getting the thing removed, so he decided to be very, very careful.
He reports to me his actions were perfect for a full four hours, at which point he was driving down the freeway when all the warning lights started coming on. He’d been practicing hooking up and removing the car from his new motorhome and, in spite of his best efforts, on the last go-round, he’d failed to flip the switch.
That time, he was lucky. He flipped the switch, and the problem went away. He then decided to be very, very, very careful, and for the next three months, things went OK, until that fateful night in Idaho.
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Panic!
Wrong! The road ended up at a ranch house protected by a large, loud dog. They stopped the motorhome before the ranch house, but there was no way to turn around. They were going to have to back away, something you don’t casually do in a motorhome when towing a car. No, you first have to remove the car. He and his wife quickly exited the motorhome and headed for the tow car. Each had their assigned duties: He was to pull the safety pins on the tow bar frame on the front of the car; she was to remove the special key they used for towing because it would unlock the steering wheel but not start the car. She would then insert the real key, start the engine, then turn the wheel and gently rock the car back and forth until the large locking pins on the tow bar could be pulled loose by Mr. Brown. She would then back the car away so he could stow the tow bar.
“We both knew our jobs, and we both started working really fast. We got even faster when we saw the guy come out of the ranch house with the rifle.” They went right down through their mental checklist and had that car separated and ready to go in less than one minute.
The rifleman turned out to be quite a decent guy, and let them pull the motorhome forward into his yard to turn around. At that point, Mr. Brown started driving his car out toward the highway, while Ms. Brown followed in the motorhome.
They were barely back on the paved road when all the warning lights came on and the transmission “slipped a notch.” (That is his phrase, not mine. I don’t know exactly what that sounds/feels like, but I got the general idea.) He immediately stopped and checked the switch. Sure enough, it was in the wrong position.
Panic & Old Learning
Reverting to old learning under pressure is a well-understood principle. It is similarly illustrated by a story regarding a fighter plane that came out in the 1960s. It had a tendency to eject the pilot whenever anything went wrong. The engineers were tearing their hair out, because there didn’t seem to be any pattern to the ejections. It didn’t matter whether the hydraulics failed or an engine flamed out, or the ailerons lost control, within about two seconds, the pilot was shot out of the plane.
Mystery solved: When they looked back over the ejected pilots’ flying histories, they noted they all had one thing in common. They had all migrated to this aircraft from the same former aircraft. The two aircraft's controls were almost identical except for one important difference: The throttle and ejection seat handle positions had been switched. The pilots flew the new aircraft with no difficulty until an emergency arose, at which point they reverted to old behavior and blew their butts out of the plane. Mr. Brown should consider himself lucky.
Slow–Motion Panic
The next day, 50 miles away, Mr. and Mrs. Brown stopped to take a side trip to view The World’s Largest Potato! or some other roadside attraction. As Mr. Brown began disconnecting the tow bar, Mrs. Brown started the car, at which point, parts of the transmission exited the bottom of the transmission with a loud bang, and a flood of transmission fluid began to form under the car. Mr. Brown was in a quandary. He was in a public parking lot with a broken car and a spreading oil slick. There was no one around to tell about the problem, and he was certainly ill-equipped to clean it up. He decided to do the only reasonable thing: He decided to make a get-away.
Different people react to transmission-failure panic in different ways. Mrs. Brown had immediately disappeared into the bathroom in the motorhome. Mr. Brown, moving only slightly more toward a “flight and fight” strategy, locked the car, hopped into the motorhome, and started pulling out.
The motorhome felt funny. It was kind of lumping across the parking lot, even though the lot was reasonably well paved. He stopped the motorhome, hopped out, and walked back to the car. The car had laid down a trail of rubber behind it. It appears Mr. Brown had failed to replace the tow key and unlock the steering column. The car was being literally dragged across the parking lot with the wheels in a left-hand-turn position.
Mr. Brown headed the car toward Boise, hoping they would either have a Lexus dealer or a Toyota dealer (Toyota makes Lexus). He drove for around an hour, waiting patiently for Ms. Brown to exit the bathroom so he could have her call ahead and find a dealer.
When he was about 20 minutes from Boise, he decided to go back and find out what was wrong with his wife. He pulled over to the side of the freeway and snapped on the parking air brake. “The freeway was really level, with grass on the center section and a broad grass area as wide as the freeway itself on my side, with just a gentle slope down,” he reported. He didn’t drive onto the grass, of course—a 30,000 pound motorhome is not exactly a SUV. He, instead, popped the brake while on the soft shoulder, unsnapped his seat belt and went back to the bathroom.
Ms. Brown wasn’t in the bathroom. Ms. Brown was in bed, asleep. Mr. Brown was not happy with this. “I couldn’t believe it. Here I was biting my nails to the quick waiting for her to come up and find out where I should be driving, and she was asleep!”
I’ve explained to him since that such a reaction is just as valid as the sorts of weird reactions he experienced.
Like the weird reaction he experienced right then:
When he saw his wife in bed asleep, he felt as though the whole world were moving around. It almost seemed mystical, some throwback to the ‘60s, until he looked out the window, and realized the whole world really was moving around. He hadn’t quite popped the brakes, and he hadn’t moved the transmission to neutral. The motorhome was off on an adventure all by itself.
“It scared the hell out of me. I was 30 feet away from the driver’s seat, and the motorhome was driving all over the grass. It could pop onto the freeway, headed crosswise, at any moment. I don’t think I’ve ever moved so fast.
“Once I was back in the driver’s seat, it got really embarrassing. At the far side of the grass area was a large RV dealership, and people were watching the crazy guy driving through the field with great interest. I had to maneuver the RV back onto the freeway, all the while trying to look like I had intended to check out its off-road capabilities. I also couldn’t slow down; if I had, they’d still be towing me out.”
He got back on the road, shaken and stirred, but alive and uninjured. Ms. Brown was no longer asleep. In fact, she was wide, wide awake. She got on the horn and found the only Toyota dealer in town. (The nearest Lexus dealer was in Seattle.) They drove there with no further incident.
It was only after they arrived that they learned the extent of their panic.
You’ll recall that the first thing Mr. Brown would do when disconnecting the car was to pull the safety pins that prevent the large locking pins from falling out. He had just finished that task when the transmission exploded. In the ensuing panic, he never looked back. When they got to the Toyota dealer, the safety pins were still out, and one locking pin had worked itself more than half-way out, while the other was almost completely out. A few more miles and the car would have torn free. “Thank God I hadn’t disconnected the safety cables [that hold onto the car if the tow bar breaks]. I could have killed someone.”
Stress Review
- Initial Panic, at the sight of the rifle, causes Mr. and Mrs. Brown to fail to flip transmission fluid switch.
- Transmission-explosion panic causes Mrs. Brown to go to sleep and Mr. Brown to drive off with the wheels locked and the locking pins unlocked. Both totally abandoned their tried-and-true towing procedures.
- An hour later, Mr. Brown, having popping the emergency air brake hundreds of times before, is still suffering sufficient psychological stress to leave the seat of the motorhome after not pulling hard enough to pop the brake on and with the transmission in Drive. The motorhome, not realizing the problem, drives off without him at the wheel.
None of the events that caused the panic were in any sense life-threatening. They were disturbing, yes. Mr. and Mrs. Brown faced possible high expense in changing the engine/transmission unit, and they faced embarrassment at being found flooding a parking lot with transmission fluid. Both of these pale in comparison to the subsequent risk to their own and other’s lives by allowing their motorhome to run away with them in it, and their car to all but become disconnected.
Mr. Brown has opted to be anonymous, to the extent that I don’t even know who he is. We were exchanging shop talk at an RV park when he mentioned owning the Lexus notorious for transmission problems. Having had the same car, one that suffered a similar, though far less colorful breakdown, I talked to him for an hour or so, and we both drove off the next day in different directions.
He’s embarrassed by what happened, although he shouldn’t be. Panic is far more common than most people imagine. To read how it affects everyone from pilots to Presidents, read the companion article, Panic! How it Works and What To Do About It
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