Another case of a truck hitting a low bridge is a lesson for everyone that map databases have flaws.
Reasons range from raw data (such as municipalities not not updating maps when roads are changed or not extended), through errors in copying, to software defects. Things hanging down are common, I saw that almost catch a high truck load on a BC Ferry boat, the driver was given a figure for clearance that did not take into account sprinkler piping hanging below the structure.
Aviation databases are rigorously checked, and updated often so changes and error corrections can be included. But even they can let pilots down – the system on a helicopter did not warn of a lighthouse because it simply had been omitted form the database.
Users should have a quality device with readable display and regular database updates, and be careful. (Seems like a good idea to crawl ahead when there is little clearance.) Drive Highway 1 east through Langley and you’ll see scars on the lower overpasses despite clear signage.
Worse are best-route calculations – people have become stuck on unsuitable roads or lost, in some cases dying from exposure.
Be careful out there.