Let's face it: due to the amount of thrust required to lift a person off the ground, practical personal jetpacks may never exist – at least, not for use in the air. Underwater jetpacks, however, are another story. We've seen a few lately, with one of the latest incorporating a novel backpack unit.
Created by Hong Kong-based AquaBeyond, the SubCruiser is intended to propel users through the underwater world, augmenting but not necessarily replacing their swim-kicks.
It consists of three main parts, all of which are hard-wired together. There's the backpack, which contains the two battery packs and the "brains," there are dual thrusters that can either be strapped to the thighs or mounted on the backpack, and there's a controller that gets strapped to one wrist.
Using a thumb wheel on that controller, users select their speed. At maximum output, a combined 10 kg (22 lb) of thrust takes them up to a claimed 4 knots (5 mph or 7 km/h). It should be noted that the controller is stepless, meaning it that smoothly ramps the speed up and down – some other similar devices can only be abruptly switched between Fast and Slow presets.
The SubCruiser is submersible to a maximum depth of 300 meters (984 ft), with one charge of its 22-volt/4.5-Ah lithium batteries reportedly good for 40 minutes of maximum-output use. And despite that depth rating, it looks like it's mainly intended for use by snorkelers. There are shots of it being utilized by scuba divers, with the backpack being worn on front (over top of their buoyancy control devices), but that looks like it could be a little unsafe.
Should you be interested, the SubCruiser is currently the subject of a Kickstarter campaign. A pledge of US$299 will get you a system, when and if it reaches production. The planned retail price is $600.
It can be seen in use, in the following video.
Source: Kickstarter