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For a long time now, I’ve wondered about the effectiveness of the Mystery Machine’s headlights. It seems to me they are not aimed very well. Let’s get to the bottom of this. Here is my analysis of the van’s headlight distance.

Exhibit A: the old-school show.

You can see how far (or not) the headlights project down the road. Let’s zoom in and take some measurements.

From this image, I count the wheelbase as 83 pixels and the headlights distance as 185 pixels for the right side and 161 pixels for the left side, an average of 173 pixels.

The actual make and model of the Mystery Machine are not known, but it turns out it doesn’t matter. The top 2 options (Chevy G10 van (first or second gen) or Dodge A100) both have a wheelbase of 90 inches (or 108 for the long wheelbase version, but looking at that screenshot of the cartoon, I say it is the short wheelbase version).

So 83 pixels = 90 inches -> 171 pixels = 185 inches of headlight distance (AKA 15.4 feet).

I found this table of recommended sight distance for various speeds (look for Table 4.2) and the ratio of speed per headlight distance is about 0.205 mph/foot.

Based on that, 15.4 feet * 0.205 mph/ft = 3.16 mph. So the maximum speed the Mystery Machine can safely travel is 3.16 mph.

I have not gone through the cartoons and calculated the maximum speed the Mystery Machine is seen to have attained, but I will say it is at least an order of magnitude more than that.

Perhaps the more modern Mystery Machine will fare better?

Exhibit B: the new-school show. Definitely not the old cel-based animation

You can see how far (or not) the headlights project down the road. Let’s zoom in and take some measurements.

From this image, I count the wheelbase as 92 pixels and the headlights distance as 147 pixels for the right side and 137 pixels for the left side, an average of 142 pixels.

I’m assuming the make and model of the Mystery Machine hasn’t changed, so it’s still 90 inches.

So 92 pixels = 90 inches -> 142 pixels = 139 inches of headlight distance (AKA 11.6 feet).

Hmm… the vehicle in the more modern show has worse headlights. My guess is that the show illustrators took into account the degradation of headlight lenses for the years elapsed (yet somehow not aging any of the characters), and the output is thus lower. Or perhaps they’re thinking the front suspension got a lot of wear and tear over the years so the front is sagging more than it used to. The rear suspension doesn’t get beat up as much because the back of the van is usually empty, so a lower front and unchanging rear suspension height would result in a worse headlight angle.

Anyway, the new show has a recommended max speed of 11.6 * 0.205 = 2.38 mph.

But since I saw them driving much faster than that, I can say they are driving very unsafely. I’m surprised the were able to even make that turn since they would have had to turn the steering wheel before they could even see the curve in the road.

In conclusion: make sure your car’s headlights are aimed better than the Mystery Machine’s headlights.

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