> ## Content Index
> Fetch the complete content index at: https://www.thefrictionlog.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# I caught myself drifting onto the shoulder at two in the morning
- URL: https://www.thefrictionlog.com/08730/
- Published: 2026-10-28T22:14:53.000Z
- Updated: 2026-10-28T22:14:53.000Z
- Description: Filed: not on record · Patched · lane departure warning in the car
- Author: The Clerk
- Tags: Patched

*My eyes closed for a second and the car drifted. I don't remember deciding to open them.* — Nurse after a night shift, 2008

By 1994 the Pennsylvania Turnpike had a new rumble strip on its shoulders, the Sonic Nap Alert Pattern. SNAP. The Turnpike knew exactly who it was for. The Turnpike's own study found run-off-road crashes fell by about two-thirds. Most new cars now carry the same idea on board: lane departure warning beeps or buzzes when you cross a line. Crash studies say it cuts those crashes some, not all, and plenty of drivers switch it off because it nags. A car that does the driving would be the real answer, and driverless taxis already carry paying riders in several cities. No one has put a date on the one in your driveway. Until then, lane warning wakes you up. It doesn't keep you up.

**For now**: if your car has lane departure warning, leave it switched on, and if you're drowsy, pull off somewhere safe and nap for 15 to 20 minutes.

### The full file

The Turnpike's engineers tuned SNAP so a truck driver would feel it in the cab without it being too harsh for cars or motorcycles. That's a narrow target. California had run its own test back in 1985, on stretches of two interstates in San Bernardino County, and found 49% fewer run-off-road crashes.

Later, wider studies were less excited. A national research report puts the cut at 15 to 22% of single-vehicle run-off-road crashes, depending on the road. The early numbers ran as high as 80%. The strips are loud for the neighbors, and awkward for bicyclists. Still, Kentucky calls them among the most cost-effective ways to prevent roadway departure crashes.

Drowsy-driving crashes peak between midnight and 6 a.m., Kentucky says, and again in the late afternoon. Two in the morning is when the strip earns its keep. Naps are cheaper.