Flying Bicycle Is Real, Takes First Flight 123
colinneagle writes "Bringing us one step closer to the hover-boards and flying cars that mid-20th century pop culture had predicted we would have by the year 2000, three Czech companies have come together to develop a functional flying bicycle. Designed by Technodat, Evektor, and Duratec, the flying bicycle weighs a little more than 187 lbs and limits its takeoff weight to about 350 lbs, according to a report from Polish bicycle news site Biketrendy. The report claims the bicycle, which is still just a prototype, is capable of staying in the air for about six minutes, although the companies working on the project hope to extend that to 50 minutes and top speeds of about 30 miles per hour. Currently, the fans propelling the bicycle are powered by a 50Ah battery."
That's what Area 51 does (Score:5, Interesting)
Seriously I think the greatest invention of the 21st C could be silent fans.
The USAF has been working on "stealth helicopters" for years. They haven't been able to make them silent, but they can make them sound like wind noise, eliminating the distinctive "whap-whap-whap" blade sounds.
Re:Gossamer Albatross (Score:5, Interesting)
There have been around 100 successful human-powered aircraft built over the years. The problem is they're not useful because we're not that powerful. A helicopter-type aircraft needs ~600W to lift a human, and only a few humans can put out that kind of power for any non-trivial period. A fixed-wing aircraft can get by with less power -- on the order of 300W in clean air w/ground effect -- but even that is a lot of power for the average person (~150W is a more typical number for an hour, and over the course of several hours ~75W).
Re:That's what Area 51 does (Score:5, Interesting)
The USAF has been working on "stealth helicopters" for years. They haven't been able to make them silent, but they can make them sound like wind noise, eliminating the distinctive "whap-whap-whap" blade sounds.
The first trick is spreading the noise out over a larger range of frequencies.
You can accomplish this by changing the rotor blade spacing to reduce harmonics.
So instead of equally spaced rotors, the distance between them is unequal, which mitigates that whap-whap-whap sound.
The second big method involves actively "flapping" the rotors.
This lets you change the plane of the rotor just enough to miss the vortex from the previous rotation.
By always traveling through smooth air, you can minimize uneven pressure waves which create noise.
The rest of the tweaks are aerodynamic adjustments to the blade tips/materials/shape.
And last but not least, throttle back and reduce the rotor speed.
Re:Noisy isn't it. (Score:3, Interesting)
I'd be skin and bones at 170. I can stay at 200 and still be under 16% bodyfat. OTOH, maybe it will scale. Get it to a base payload of about 250 lbs, and I'd give it a try.
If you want diet that tastes like sugar, there are some options:
For the big producers:
Pepsi's Aquafina FlavorSplash waters - grape, raspberry and wild berry, use just Sucralose, (a 0 calorie substitute) last I checked. No other Pepsi products use just Sucralose to my knowledge, but rather mix it with something else such as Apartamine and/or Ace-K. Ace-K is a big issue for diet soda safety, in that it's not commonly mentioned and less seems to be known about it than other non-sugar alternatives. Sucralose occasionally tends to upset digestion, but mostly in people who are consuming quite a few cans a day, and switching over to it gradually helps - 80% or more of people who do a lot of sodas a day, do OK by gradually switching and giving the digestive system a couple of weeks to adapt. There are no Coca-Cola products with just Sucralose, as far as I can tell. Diet-Rite cola is usually made with just Splenda (sucralose), as is Diet RC cola. It doesn't hurt to check the labels on any of these, as there may be some canned or bottled in other countries than the US that isn't exactly to the US formula.
Honest Fizz is a bit pricy, running about 1.20$ US a can. It's sweetened with a mixture of Stevia Leaf Extract and Erythritol. Erythritol is a complex alchohol and means one can has about 5 grams of carbs. (that's not a lot, but it's a few calories - about 30-40). Just like Sucralose, some people get increased gas or even cramping from Erythritol, some don't, at least if they aren't drinking eight cans a day. Just because one of these substances causes discomfort in some users doesn't mean the other one will affect the same people.
For pure Stevia sweetener, you could try Zevia, which now has 15 flavors, including Mountain Zevia, Doctor Zevia, and Caffine Free Cola.
I don't get paid to plug any of these. I don't own stock in them and nobody with them has asked me to say anything about them.