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PROPULSION REALITY CHECK
Perhaps the most common question inquiring minds have about space travel is:
"how can rockets function in the vacuum of space - or in very thin air pressure"? To this question, NASA (and its believers) unfailingly respond roughly like this:
"that's because rocket thrust is not achieved by pushing against air. Air has little or no influence on rocket propulsion. What makes a rocket move is the rocket fuel pushing onto itself. Have you ever heard of Newton's 2nd & 3d laws of motion?" Well, the claim that "air density has NO influence on rocket propulsion" has to be the silliest of all NASA lies. This is akin of saying that sea water has no influence on the motion of ships propelled with waterjet engines (see p. 4 below). NASA fans will then bring up the age-old example of someone standing on a wheeled office chair, throwing a medicine ball. Their tedious, triumphant punch line will always be:
"See? As you throw the ball - the chair will move in the opposite direction"
1: CAR PROPULSION
The question is: just how much force / thrust can be produced in this way? Could a car be propelled by these NEWTON laws alone - with sufficient efficiency? Why then don't we apply these amazing forces here on Earth? Anyways, here's my proposal for a "NEWTON car". Just imagine, ladies and gents: if this works out - we could soon eliminate our dependence on air-and-fuel-propelled vehicles:
Yes! NASA teaches Newton-car experiments to kids!
http://www.nasa.gov/pdf/153412main_Rock ... on_Car.pdf
Will I be able to sell this invention to General Motors? Volkswagen perhaps? I doubt it - but wish me luck! Yet, the principle of the above F1 force is what NASA claims to propel their magic rockets in a (near)vacuum. It also works, apparently, for precisely steering / docking their space vessels launched at tremendous orbital speeds - and to brake / decelerate them for re-entry so that they don't burn up in a fireball - like meteors do.
2:JET ENGINE PROPULSION
Now, we the people may never have launched a rocket into outer space - but this doesn't mean we rocket-less earthlings have no empirical / comparative knowledge with which to gauge the plausibility of NASA's claims. For one thing, we know that jet airplanes need air to be able to fly. They just won't fly in the absence of air. At a certain altitude, a jet plane will be starved of air - and both its engine and wings will cease to function. The plane will eventually stall catastrophically - and plummet back to Earth. There's no way, for instance, for a modern-day F-18 fighter to just point upwards and reach the
Kàrmàn line - considered to be (at 100km of altitude) the threshold between our atmosphere and outer space.
THE KARMAN LINE
When studying aeronautics and astronautics in the 1950s, Kármán calculated that above an altitude of roughly 100 km (62 mi), a vehicle would have to fly faster than orbital velocity in order to derive sufficient aerodynamic lift from the atmosphere to support itself. At this altitude, the air density is about 1/2200000 the density on the surface.
For an airplane that is trying to fly higher and higher, the thinning air gives less and less lift, requiring a higher speed to create enough lift to hold the airplane up. There comes an altitude where it needs to fly so fast to generate lift that it reaches orbital velocity. The concept of the Kármán line is the altitude where the flying speed necessary to aerodynamically support the full weight of the airplane would be equal to orbital velocity (assuming the wing loading of a typical airplane).
http://en.wikipedia.org/wiki/K%C3%A1rm%C3%A1n_line
Only NASA knows how they managed to send their "X-15" beyond the Kàrmàn Line (at 107km)- back in the sixties!
http://www.astronautix.com/craft/x15a.htm
3: BALLOON PROPULSION http://hypertextbook.com/facts/1997/CassandraEng.shtml
There is also a limit beyond which balloons won't go. They will reach a (theoretical) maximum of 43km of altitude - and no further. That's quite simply a physically-dictated limit: no gases we know of are light enough to ascend beyond that altitude with a balloon. At that point, the air (atmosphere) is too thin and the balloon will be very much like a piece of wood floating on the surface of the ocean. Indeed, this brings us nicely to our next - and most interesting - form of propulsion: let us now imagine our Earth's atmosphere (and the air that we breathe) as a big, water-filled ocean - and let's conceptually replace oxygen with the thicker liquid known as 'water':
4: WATER-JET PROPULSION http://en.wikipedia.org/wiki/Pump-jet
In the thicker liquid known as water, the most modern method of propulsion is called "water jet, pump-jet or hydrojet". What do such jets do in order to propel these ships? Well, they pump out at great speed a jet of water into ... water! Surely, this propulsion can only take place if those waterjets are immersed in water. Now, imagine the above-pictured, docked / serviced ferry (filled with imaginary water tanks) suddenly switching on those powerful hydrojet engines at full throttle. Do you think the ferry would move forwards - or would the water (with only air to push against) just flush out from those two nozzles? Well, the ship would probably rock about a little - and perhaps even fall off its flimsy support pillars. But it surely wouldn't start travelling forwards at its seafaring cruising speed.
ROCKET PROPULSION
But those NASA ships (such as the 100.000+kg Space Shuttle) we are told, are a wholly different thing: neither air/atmospheric pressure nor gravity is of any concern to them - for producing either lift or combustion... As they soar towards the Kàrmàn line, where air/atmosphere is
2,2million times thinner than at sea level, the NASA rockets will keep providing the necessary, EVER INCREASING rocket thrust which any airborne object has to maintain in order not to stall and plunge back to Earth. In fact, NASA claims that the Space Shuttles achieved the required
escape velocity of 27.000km/h. This, in spite of jettisoning their two main rockets (the SRB's) at only 45km of altitude, leaving the Shuttle (with its weeny three rear rockets) and its huge main tank to pull away from 90% Earth gravity, in near-vacuum air density towards the Kàrmàn line, for another 55km-long ascent ...
http://en.wikipedia.org/wiki/Space_Shut ... et_Booster
I am ready to hear evidence to the contrary, but as far as I can gather at this time of my life, mankind still hasn't overcome the - perhaps insurmountable - problems of propelling any earthly object into this magical "outer space" - where all things apparently freely orbit / float around - in circular or elliptical fashion - and with little or no fuel needed.