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The Truth About New Jet Pack Hype

An anonymous reader writes "This week a sub-$100,000 rocket belt was unveiled and will be on sale this summer, but that's the sad thing: it's still not a real jet pack. Here's a fascinating inside look at the human-flight industry, full of law-suit scandals, technical difficulties, fuel-economy woes and endless delays. The good news? It all points to the next generation of rocketeer research, with real applications for medical rescue and military technology actually coming on the horizon. From the article: 'With a little patience, and a little funding, we could actually have the pleasure of grumbling over regulatory issues we never dreamed possible. Like being limited to specific kinds of air strips, because the jet strapped to your back is classified by the FAA as an ultralight. Or being required to wear a ballistic parachute, because Amarena's Thunderjet design could reach altitudes as high as 10,000 feet (and, for the record, speeds of up to 160 mph, provided someone can solve wind-resistance issues).'"

3 of 205 comments (clear)

  1. Re:Why is it "not a real jet pack?" by Frosty+Piss · · Score: 3, Informative

    A jet engine is a reaction engine that discharges a fast moving jet of fluid to generate thrust in accordance with Newton's third law of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, pulse jets and pump-jets, but in common usage, the term generally refers to a gas turbine Brayton cycle engine, an engine with a rotary compressor powered by a turbine, with the leftover power providing thrust. Jet engines are so familiar to the modern world that gas turbines are sometimes mistakenly referred to as a particular application of a jet engine, rather than the other way around. Most jet engines are internal combustion engines but non combusting forms exist also.
    -- Wikipedia

    Sounds like a jet pack to me.

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  2. Comment removed by account_deleted · · Score: 5, Informative

    Comment removed based on user account deletion

  3. Re:Jetpacks are just a bad idea by AndersOSU · · Score: 3, Informative

    Decreasing jet noise is in fact very difficult, but it is also a major area of research in mechanical engineering departments across the country.

    No, unfortunately this massive research thrust isn't aimed at making jet packs more practical, but rest assured, gains in reducing aircraft jet noise could be applied to jet packs.

    The noise a jet makes is the result of turbulent mixing of the high speed jet with the low speed surrounding air. Some solutions are simple, like the chevron edges on the Boeing 787 others are a bit more complicated involving heating, cooling, or electrically charging the exiting jet. The goal being always to make the mixing of the jet and surrounding air less turbulent. Suffice to say you're not likely to have a picnic next to an operating jet engine anytime soon, but it is an active area of research.