The 85th percentile

There are probably more opinions on what is or isn’t a safe speed than there are people. But our opinions (especially mine) don’t count for much. So, how are speed limits set?

Traffic engineers gather data. First they consider the road in question.

A speed study consists of a review of the function, design and actual use of the road. Is the road intended for heavy commuter traffic or light local traffic? How wide are the lanes? How wide are the shoulders? Is it straight or curvy? Are there a lot of intersections? These and many other questions about the road get answered in the study.

(Even before that, though, highway engineers will have designed the roads with certain speed and traffic criteria in mind.)

Then traffic engineers measure how much traffic there actually is and how fast it’s going.

Then the engineer conducts a traffic count to determine the actual quantity of traffic and how fast the vehicles drive. This data provides the “85th percentile speed.” That term just means the speed at which 85 percent of the cars travel. On a well-designed road with an appropriate speed limit and effective enforcement, the 85th percentile speed should be pretty close to the posted speed limit.

Ah, but is the speed 85 percent of the traffic drives sufficiently safe?

The engineer also researches the number and rate of collisions on the road and compares them to the collision rate for the overall jurisdiction. Collision rates are the number of crashes per million miles traveled.

Then the engineers make their recommendations to the higher-ups. If there are too many accidents, lower the speed limit. If there are fewer accidents than on similar roads/streets, keep the speed as it is or consider raising it. If politics doesn’t get in the way, then the posted speed limit will probably be reasonable. Or reasonable enough. There will still be collisions. There will still be fatalities. Because there are no perfect speeds or perfect drivers. Speed limits are a compromise. Driving is a gamble—one that most drivers win.

Impulse purchase

I started the day with the vague plan to wander through the mountains of eastern San Diego County, starting with Old Highway 80 (the predecessor of I-8) and then turning north through Mt. Laguna, Julian, and Warner Springs. I'd find a dispersed camping spot somewhere in the Cleveland National Forest.

But then, only about 30 miles down the road, I saw a sign for a campground. Some part of me said, "Turn in there." So I did.

Boulder Oaks Campground serves as a departure point at the southern end of the Pacific Crest Trail. There were about a dozen hikers chatting, checking their packs, filling their canteens and using the toilet before setting off on their 2,600 mile trek. I'm far less ambitious, so I found a nice campsite and settled in to just enjoy the non-desert surroundings and perfect weather. It was an excellent deal at $7.00/night with my senior pass.

Among the rocks

Flying saucer wreckage, right?

Thermal ups and downs

I’ve left the deserts of Arizona and California to visit the Pacific Coast for a few days. That meant a sudden elevation shift as I drove west along Interstate 8.

El Centro, California, is 40 feet below sea level. It was shorts and air conditioning weather yesterday afternoon. About 93 degrees. Then 25 miles west, at Ocotillo, the highway begins to climb into the mountains: 3,000 feet in 12 miles. And the temperature rapidly drops.

It’s a basic principle we nomads learn: as you go up the temperature usually goes down, and vice versa. So we can avoid troublesome temperatures by shifting elevation, not just latitude.

On a cloudless day (like yesterday), temperature decreases approximately 5.4°F for each 1,000 foot gain in elevation. So it should’ve been in the 70s when I pulled into Coyote’s Flying Saucer Retrievals & Repairs atop the first summit. But it was in the 60s because of another factor. Hot air rising in the desert was drawing cool ocean air over the mountains.

This is where the 5.4°F per 1,000 feet rule breaks down. It’s not going to get warmer as I drop out of the mountains to the ocean because Pacific currents coming out of the north bring colder ocean temperatures which creates a layer of colder air along the coast.

That’s why this visit to the Coast will be short. Say hi to my Los Angeles friends, stare at the ocean for a while, then head back inland in search of perfect weather. But I'll be back. More than once. Autumn is a great time to be on the West Coast.

Lou explains

(When I upload videos to YouTube, they give me a choice of three frames to use in the preview. Lou says this one makes him look like an 80 year old homeless drunk. I agree it's not a fair representation, but it's much better than the other two. I suspect YouTube's software purposely looks for the least flattering video frames. But you'll see the real Lou if you watch the video—especially his smile at the end.)

Ernie's Garage gets it done

Ernie said to come by the shop at 8:00 and he'd get my power steering pressure hoses replaced right away. That's exactly what happened. In and out in about an hour.

The people who formed these hoses must also make trumpets and tubas

"So," you might be wondering, "what did it cost to have the work done?" I supplied the hoses so all I had to pay was labor. The going rate at most shops is $90 an hour. And they might've claimed it was a two- or three-hour job. Ernie charged me $60, including new fluid. Excellent.

You can judge a mechanic by the quantity, quality and age of his posters

My nomadic friend Dale said the following in a video:

“Everybody always says to us, ‘Be careful,’ you know, ‘Be careful out there, be careful, there’s all kinds of bad people. Be careful!’ And we really haven’t met any yet. We’ve just met nice, kind people.”

The warnings are slightly amusing, because all of us are part of someone else’s warnings to their friends and loved ones. We are part of their great, scary unknown. Decent people afraid of decent people only because they’re outside each other’s bubbles of familiarity.

Yes, there are bad people out there. There are also bad people in your home town. But they’re sort of the devils you know. It’s the devils you don’t know that cause anxiety—even though they probably aren’t any different or more numerous than your local devils.

One of my favorite sayings, which I’ll have tattooed on my arm someday soon, is:

Travel cures ignorance

What are things like in a distant place? Go and see for yourself. What are people like several states, several borders, several cultures away? Go and see for yourself. Form your opinions from personal experience and reality, not from hearsay, uninformed assumptions or not wanting to leave your comfort zone. Your mind and your life will expand.

If you insist

What to do when your truck dies

With a little imagination and plumbing you can turn a truck into a fountain, and a gas station/market into something more than a place to fuel up and pee. That's what the Why Not store in Why AZ did.

Wanderlust

It started as a discussion of “slow travel.” Go to a place, stay days or weeks, immerse yourself in it, avail yourself of all it has to offer, then repeat the process at the next location.

I’m not very good at this. I zoom from point to point after brief stays. I experience a tiny bit of the place then move on, telling myself I’ll save further exploration for subsequent visits.

I read an article about whether you have wanderlust. Some of the indicators were:

You dream of other places after you've just gotten somewhere.
You're never content in one spot and that one spot is always old.
You never want to be where you are, but couldn't wait to get there before you were.

Yeah, that’s me. No matter where my body is, my mind is down the road somewhere, anywhere.

However, the discussion of slow travel swerved off course (as online discussion often do) when some people claimed traveling slowly required driving slowly, or that driving slowly was all there was to traveling slowly. That’s when my online wanderlust told me it was time to leave this discussion for some other. Somewhere. Anywhere.

Maybe that shows what’s at the root of my wanderlust. I don’t want to stay anywhere long enough to start disliking it. I don’t want to discover the negatives. I want to leave the metaphorical party while it’s still fun, before the drunken brawl starts.

Speeding or not?

How well can you judge your speed without looking at your gauges and when there are no other vehicles around? Science says probably not that well. We tend to overestimate our speed on narrow and curvy roads and underestimate it on wide and straight roads.

How well can you judge the speed of a passing vehicle when you’re stationary? Science says probably not very well. Things maintaining a constant speed seem to speed up as they get closer and slow down after they pass. Also, given the same vehicle driving past on the same section of road, but at different speeds, science says we aren’t all that good at assigning accurate rates.

So, how well can you tell how much faster than you the vehicle that just passed you was going? Probably not very well. Even if we try to ignore the environment whizzing past and just concentrate on how quickly or slowly the gap between you is widening, we’re not great guessers.

Our ability to judge other drivers’ passing speeds decreases as our own speed decreases. If you prefer driving no faster than, say, 55 but the speed limit is 70, people passing you within the speed limit may seem like they’re screaming by like maniacs.

Sure, there are speeding jerks out there. Yell at them, flip them off, hope there’s a cop ahead. It’s your right. Just use it judiciously.

How fast do I drive? I usually go with the flow of traffic. When there’s no traffic to flow with I find I ease off a little. If the road is really smooth and there’s a tailwind I might accidentally creep over the limit. Oops, I had no idea I was doing 80, because Science.

Sign of the times

It's better to have a crazy dream than no dream at all

"Mad" Mike Hughes finally rode his home built steam rocket about 1,875 feet above Amboy, California. And lived to tell about it. That's quite a feat for a self-taught rocketeer. Never mind he's a flat-earther. He had a dream, he worked on it, fought through setbacks and eventually pulled it off.

There was a time I had no dreams beyond the vague hope of escaping a life I'd stopped enjoying. My therapist asked what I would do if I were free. I didn't have a clue. But it eventually came to me. I worked on it, fought through setbacks, and now here I am, living an uncomplicated, mostly carefree, life wandering around the West. A lot of folks would say that's crazy. Because it's not their dream.

After the wind and rain