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Comment by eadz | Hacker News Reader

The competition referenced may be the Martin Jetpack. https://en.wikipedia.org/wiki/Martin_Jetpack

It is listed on the ASX stock exchange, although hasn't released a product to market yet. However, I think they may be further down the line towards commercialisation.

The JB-9 looks more lightweight and fun, but the Martin has a parachute...

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A parachute doesn't really make it safe. There is still a large "dead zone" where it would be too high for the pilot to survive a crash but too low for the parachute to work. Unlike a helicopter, the propulsion system doesn't have enough inertia to perform a power-off autorotation.

Some designs for larger powered lift vehicles have somewhat solved that problem by using multiple engines with cross-linked drive shafts. But that increases size, weight, and cost.

These jet pack devices may find a very limited niche market. But they don't have much of a real use case beyond looking cool on video. Most potential buyers will still prefer small helicopters, or drones.

I wonder if they could put in an electric hybrid system that could give a few seconds of propulsion to slow decent in the case of losing gas power. I have no idea though if that would even make sense because it seems like it would just increase the weight with no benefit.

Sure but it would require a complex, heavy, and expensive set of electric motors, transmissions, clutches, batteries, etc. At that point you might as well just use a helicopter.

Rocket chutes[1] help with the altitude problem but there are lots of "dead" zones.

[1] https://spinoff.nasa.gov/Spinoff2010/ps_3.html

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