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The Coming Air Age
Lovejoy writes "Sixty years ago in The Atlantic Monthly, Igor Sikorsky wrote The Coming Air Age. "Any of us who are alive ten years after this Second World War is won will see and use hundreds of short-run helicopter bus services." He goes on to write about personal helicopters which fit in large garages and that helicopters that are easier to drive than cars, etc.. So, will personal flight ever be viable? Do wildly wrong predictions like this give futurists pause? I think they should."
NO, the helocopter dies, and you autorotate down to the ground. At any decent helo flight school, they will force at least 3 practice autorotations, where they actually shut off the engine. They are no more dangerous then having an engine shut off in a Porsche at 140 mph. It just takes a little more training, which wouldn't be a bad thing for most car drivers.
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Predictions like this were made during and after WW1 as well, for the private use of planes. For a time in the 20s and early 30s, it seemed as if it might be true: small biplanes like the Moth were cheap and easy to fly, and could be stored in the garage and assembled for a trip.
But I don't know why it never took off...maybe the intervention of WW2, cheaper cars, better roads...
Not quite true. When the power goes in a helicopter, there's a lot of angular momentum stored in the rotor, and aerodynamic effects allow you to spin the rotor even faster by angling the blades appropriately as you, er, plummet.
As you approach the ground (probably a lot faster than you'd like), you angle the blades to bite into the air, trading lift for angular momentum. If you do this correctly, you may be able to save your butt.
--Larry
Never attribute to malice that which is adequately explained by incompetence
That's assuming you have a place to land, the rotors are still in one piece, the rotors are free to auto rotate, the other control surfaces are still functioning. There is plenty of footage of autorotation accidents.
Having an engine shut off at speed in a corner is vicious, suddenly no drive going to braking. When your car is balanced at speed any change in force is a big problem.
Until it's cheap. I want my Silver Surfer fantasy damn it now just hurry up and make it happen.
It won't happen with current tech, too expensive and liable to fail. We need something like anti gravity, ducks the punches thrown by physicists, or something similar that provides oodles of lift for a few cents.
Having surfed, skateboarded, snow boarded I'm all set to flyboard.
There is a very group at work to fix some of the most serious problems with helicopters. Very promising stuff. See http://www.cartercopters.com/
According to the NTSB database, there have been about 5100 heli incidents/accidents since 1/1/1980. 879 had at least one fatality.
:)
So, it's not too bad, but compared to the number of general aircraft fatal/nonfatal incident ratio, it's higher.
Of course, that could be due to the higher incident of runway incursions and planes taxiing into other planes causing minor damage, which is included in these numbers. Those kinds of things don't often happen to helicopters, since, well, they don't taxi.
I've had enough abrasive sigs. Kittens are cute and fuzzy.
One reason aircraft will never be as common as cars, is the maintainance involved. Aircraft must be constantly maintained, whereas cars can be ignored. The other is ease, a bad driver will cause accidents or close calls, a bad pilot can kill many people.
The truth about modern flight is, it's so safe that the only thing that will bring any plane down unsafely is a bad pilot or a catastrophic failure. This is why people don't survive airline crashes. An airliner doesn't crash unless it explodes, or has a major structural failure.
The hardware isnt much of an issue, but cost and training required is.
One thing that most people don't understand is how hard it is to fly a helicopter. It is not as simple as driving a car where you go and take a test to prove you understand the traffic laws and then go out on a road course with a DMV person for 15 to 20 minutes.
It takes years of schooling in order to be granted a helicopter pilots liscense. This is very costly, and requires a lot of time.
It is not uncommon for people to go to college for flight (airplanes), and once successfully passing their flight exams to go on and study helicopter operation.
My little sister is currently studying to be a commerical airline pilot and it will take her 4 years at the number flight school in the USA. Then if she wants to persue helicopters she has to take more classes and spent a lot more time gaining the airtime in a helicopter with an instructor, only then will she receive her helicoptiers liscense from the FAA. The FAA is strick and sometimes tough, and this is for good reason, would you trust any idiot with a piece of machinery like this? If they crash the thing into a crowded area they kill a whole lot people.
Helicopters are not like cars, when you wreck a car, most of the time you can survive, or if you die, you don't kill anyone else. When you crash a helicopiter you are probably automatically dead.
In Sao Paulo, Brazil, there are somewhere around 300 private helicopters that those who can afford them use to avoid traffic and crime. They use them just like the plebes use cars. The best article I found on the topic is at aviation today (here).
Of course, having 300 'copters in a city of unpteen million isn't exactly what the man predicted, but the patter of use is consistent.
The currently designed helicopter will not be the flying car of the future. As master Yoda would say "No, there is another". Meet the cyclogiro, our Navy's latest secret weapon, and one of Russia's finest inventions. ;) They operate on the concept of cycloidal propulsion (see Google), which is mechanically complicated but more efficient and quiter than conventional designs.
But there really is no negative heat. You can have less heat or less gravity, but once you are at zero thats about it as far as anybody knows.
Mass, at least is equivalent to inductance, so gravity can cause an object to oscillate. Heat doesn't even have that. Heat will flow from warmer to cooler places, but thats about it.
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Carter Copters has been working feverishly for several years now on a vertitcal take off and landing aircraft. That combines the traits of helicopters and fixed wing aircraft with GryoCopters.
The specs are pretty impressive. Coast to Coast on 1 tank of gas. 450mph cruise speed at over 35,000 feet, Zero Roll take off and short field landing. 5 Passengers. Plus luggage.
Here are some pics and vids. They had a good demo at the OSHKOSH Air Show
Two Towers-Two Worlds.One seeks triumphs and freedom for man.The other deems man unworthy and wrecks them.
Of all the "personal flight" ideas out there, the Moller skycar seems to have the most potential. I heard the designer, Paul Moller, being interviewed on Coast to Coast AM recently, and was captivated. Looking at the design, it seems very "car-like," with no exposed rotor edges or wings; it basically looks like a car with small jet engines instead of wheels. During the interview, the designer made a big point of explaining the integral safety systems: each turbojet is actually two turbojets, so if one fails the other takes over; there are three separate computers on board (one primary, two backups), etc. It runs on regular gasoline, gets mileage comparable to a car (over 25mpg), is quiet (85dB @ 50 feet, and they're working to reduce it further), and most importantly, is a VTOL (vertical take off and landing) craft. They've been developing this for the last few decades (check their design history on the site) and are working with the FAA to obtain "powered lift" certification for the Skycar- on the interview I remember one of his points was that getting a license for the Skycar should be easier than getting a driver's license.
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But internal combustion engines are much more efficient at trapping the expanding combustion gases and converting them to work. Turbines lose a lot of efficiency in the conversion of energy to mechanical work.
The difference isn't nearly as bad as it used to be, but turbines still aren't as efficient. They are much more reliable, however, so their overall cost of operation is less when scaled to suit airliner size aircraft.
Here's proof. One airframe design that has two variants, a piston-powered variant and a turbine-powered variant, is the Piper Malibu. The Mirage is piston powered and the Malibu is turbine powered. Here are the relevant specs:
Piper Malibu Mirage:
Piper Meridian:
Now, the power requirements due to air resistance vary by the cube of the speed, and the fuel burn varies directly with the amount of power used. So at 25,000 feet, the Meridian is using 1.44 times the amount of power that the Mirage is using. But if the specific fuel consumptions were the same, then the turbine would burn 1.44 times the amount of fuel, or 26 gal/hr. But it burns 37. And even if the fuel burn were the same, kerosene has a higher energy content than gasoline. So the turbine is less efficient.
Another way to prove it is through the specific fuel consumption values. A piston engine uses about 0.45 lb/hp per hour. The PT6 uses 0.53 lb/hp per hour. So the PT6 burns more fuel, from a source that has more energy.
Oh, yeah: and the turbine is a lot more expensive. But that probably has more to do with General Electric's monopoly (or so I've heard) on the processes used to produce the fan blades than anything else.
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If you mean ultralights, the best way to get more info would be to visit your local flight school and ask around. They might try to sell you on a private pilot license instead - that's where they make their money - but they're very likely to know the members of the local ultralight community, and be able to tell you who to call, especially if you mention you might want to pay them (the flight school instructors) for some meteo class time and/or theoretical classes. (Which *would* be a really good investment if you're gonna go ultralight flying anyway, hint hint.)
:-/ *Well* below a hundred knots, though, figure on maybe 60-80 mph airspeed as a normal cruise, possibly less. Altitude is largely constrained by visibility - ultralights are VFR only, so you *must* be able to see the ground (including a clear horizon) at all times, and you can't go even near clouds.
The short of it is, just about anybody can fly an ultralight after a couple dozen hours of instruction from a certified ultralight instructor, but you can't fly them just anywhere. Don't plan on landing at - or even going near - particularly busy airports; landing on private property is okay, so long as you have the landowner's permission; public land _should_ be fine so long as you don't make a mess or piss anybody off, but don't quote me on that.
Technically, it's illegal to overfly crowds and developed areas, and the FAA will interpret that law as any gathering of one or more people and/or a single house, *if* you do something that pisses them off (that is, if you make a ruckus and get negative headlines, basically). There are other places it's illegal to fly, as well, and you should be thoroughly trained on the details before you're signed off for solo flight. Your local flight school people will know.
You do not need to file a flight plan unless you want a search-and-rescue operation to be mounted should you fail to call in to close the flight plan on time - that's all flight plans are really for, anyway. As for speeds, the maximum allowed by law for an ultralight is - er, I forgot. Sorry.