One of my favorite hacks is the rather improbably piece of engineering known in Thailand as a longtail boat. They function as taxis and tour boats in the many waterways of Bangkok. […]

When you look at them when they get closer, you see a truck engine mounted on the stern with a long piece of pipe stretching out toward the bow that the boatman holds on to. There’s another piece of pipe welded onto the transmission pointing out toward the stern [.]

When the boatman pushes on his piece of pipe, it rotates the engine left, right, up or down. When he pushes down, it rotates the tail upward and you get to see the business end of the beast: a naked propeller just hanging out there.

Safety is not a real concern here. Balance is pretty dubious too. These boats are pretty narrow, 4ish feet at best. They’re really just evolved canoes. It must take an amazing amount of skill to stay balanced, navigate, and not kill anyone. At speed …

The engines are just regular truck engines, mounted on a U shaped yoke, bolted to the stern. Some of the engines are very large—they wouldn’t look out of place in a large Fruehauf tractor. Not a lot of standardized rigs—lots of welding fun. A truly glorious hack.

It’s not well known that those boats originate from a change in the British government’s motor vehicle Construction and Use Regulations in the late 1960s. What with the new motorway construction programme well under way, the (largely old) truck fleet had begun to get in the way. So the then Ministry of Transport introduced a minimum power-to-weight ratio.

This meant that a ton of trucks with Gardner LX 105hp (mostly) or Perkins P4 engines suddenly became obsolete. Exporting second-hand trucks to places that would accept them (essentially, the third world) was not great business, so they were either scrapped or retrofitted with more wallop. Hence a mass of very reliable, very user-serviceable diesel engines going begging.

Some sly fox saw a chance, and went round the country buying the engines and shipping them to Hong Kong and Singapore for sale to chandlers. As the engine arrived complete with the reverse box and the end of a propshaft, they just put in a length of shaft and a prop. Local boat builders came up with the rest and a new, unmistakable craft was born.

They still have (even brand-new ones with much later power units, radar and GPS) the traditional eyes on each side of the bow, a custom recorded everywhere from the Mediterranean to Japan and back into pre-classical antiquity.