What if Your Car Couldn't Stop Speeding Up?

You're on Interstate 80, crossing the Utah salt flats with the cruise control at eighty. Then the needle drifts past it, and it keeps going. You pass a highway patrol car that can do 148. You run up the length of a freight train, keep pace with a jetliner, and go through the sound barrier on the same salt where Blue Flame set its record. Your hood starts to glow. The Sun sets behind you in seconds. Nine minutes after the speed limit, the road curves away beneath you faster than you can fall onto it. The numbers are real. The speed limit there is 80 mph. A Ford Police Interceptor Utility tops out at 148 mph in the Michigan State Police tests. Arie Luyendyk's 1996 Indy lap was 237.5 mph, Japan's L0 maglev hit 374.7 mph, and a 787 cruises at about 560. Blue Flame ran 622 mph on the Bonneville Salt Flats in 1970. On a 62 °F October afternoon sound travels at 764 mph, a .30-06 bullet leaves the barrel at about 1,984, the SR-71's record is 2,193 and the X-15's is 4,520. The temperatures on the hood come from the air piling up in front of it (steel glows red at 977 °F, which the nose reaches near Mach 3). Orbit at ground level takes 17,694 mph, but driving due east the spinning Earth gives you 789 of it, so the speedometer needs about 16,900. The weight you lose on the way is real too, and so is the sunset coming early: every mile east brings it 4.6 seconds sooner. Some of it isn't real. The interstate is made straight and endless past the salt flats, and empty once the police close it. A real car would come apart long before Mach 3; in this story it holds, and you can still breathe under a 2.9 g push. Air this fast at ground level would wreck everything near the road, and the glowing air around your car is drawn, not simulated. The very last thing that happens is made up. You drove for nine minutes. Coast to coast would have taken you ten. CHAPTERS 0:00 Cruise control 0:55 The trooper 1:17 The end of the dial 2:02 The rest area 2:08 The freight train 2:28 The road is closed 2:50 The jetliner 3:15 The sound barrier 4:16 The end of the salt 4:36 Red-hot 5:00 The mountains 5:28 Faster than anyone has flown 6:08 The air on fire 6:52 Out of Utah 7:55 Sunset #whatif #science #speedofsound #orbit