So to proceed. The points of contention with my part 1 so far have been the effect of air on a rocket, Newton’s Third Law, the rate of fuel consumption, and the feasibility of satellites existing.
Air and rockets.
When I said that,
I was keeping in context of Newton’s Third Law (NTL). And I stand by what I said. If there is a specific rebuttal you have to that point I made, and the further expounding of the point below, please post it for the benefit of all readers and posters.The answer is that air in the atmosphere plays an inconsequential part in the flight of a rocket or missile.
When I say “inconsequential” I mean that I am ignoring factors such as air resistance the rocket encounters as it moves, and thus the whole aspect of maintaining stability in flight. Here an aerodynamic shape is key for stability, and to minimize the rocket profile, and fins (if any) are kept to a minimum. But usually the case is to have a good, stable shape.
When I say air is inconsequential for its movement it’s a sign I’m not talking about the usual flying vehicles. Simon, have you ever noticed the sudden increase in speed in planes through their history? The Wright Brothers’ first plane had a maximum airspeed of 6.8 mph, in 1903.
The P-51 Mustang had a maximum airspeed of 440 mph, in 1940.
The fastest propeller plane, XF-84H Thunderscreech, had a max airspeed of 0.83 Mach, equating to 525 mph, in 1955.
There is a leap in max airspeed as jet engines were invented.
The HE 178 had a max speed of a respectable max airspeed of 380 mph, in 1939.
The Avro Vulcan, a rather hefty bomber, had an impressive max airspeed of 0.96 Mach, i.e. 645 mph, in 1952.
And the SR-71 Blackbird had a mindblowing max speed of 3.3 Mach, i.e. 2200 mph, in 1964.
(All figures taken from Wikipedia)
Can you guess why jet engines were much faster than their propeller driven counterparts? It’s because whereas one group used air pressure differences between the front and back of its blades to slice through air to move forward, the other worked quite differently. Jet engines superheated the air using turbine fans and combustible projects to force the exhaust out from their back.
The similarity between jet engine aircraft and rockets is that they rely on speedily expelling an exhaust to push their bodies forward. This clearly demonstrates that relying on air has a limit to how fast you can fly through it using propeller blades for propulsion because the materials and engines in experimental propeller aircraft were reaching a ceiling of sorts in what more could be done to fly faster.
Obviously air and the atmosphere plays a larger role for atmosphere flying planes (i.e. those that do not ‘fly in space’) because they manoeuvre using the air and thus have relatively large wings to house ailerons for such a purpose. A missile will manoeuvre and thus will manipulate the shape of its nozzle in tandem with using fins for stability. You might imagine this as you would picture a jet fighter shooting heat seeking missiles.
Is this “my opinion”? No. My primary joy is learning and evaluating what I do know. To present my own views as fact is contrary to my principles, and doesn’t make much sense.
I’m not understanding your point here. NASA may state the same thing, however nobody has a monopoly on the truth. If you have a rebuttal to Newton’s Third Law in relation to rockets perhaps it would be a good idea to state it again for the benefit of the readers.
Rate of fuel consumption.
You quite elegantly put how a rocket will be in a spot of trouble when its fuel runs out. Unlike a plane which can glide down when its engines stop, a rocket is likely to just fall rather clumsily. Again I’m not sure what this point of yours is meant to prove. If there is sufficient fuel loaded for the journey that is to take a predicted period of time under a constantly changing mass, then there is no unfortunate dropping out of the sky or empty fuel tank misery. This is very much true for cars, electric cars, boats, planes, and plane missiles. So does the idea sound wacky to me? No, as it’s clear that running out of fuel before reaching space is a bit of a problem.
Now for a rocket or body that has been propelled into space, assuming gravity is “off” for the moment and so is air resistance, then that body will continue at the velocity is was accelerated to. After all, there is no gravitational pull to make it orbit another body, or accelerate it downwards, or air resistance to slow it down.
Feasibility of rockets and satellites.
After reviewing the arguments against the rather simplistic model of a rocket described in this topic, I’m still ambivalent as to what the main issues with it are.
NASA may explain to me how to milk a cow, but as it stands, they cannot manipulate what is known to be true, however much they may create fantastical imagery that is inconstant with itself.
In space, in accordance to Newton’s Second Law such objects travelling at a certain velocity will continue to move at equilibrium unless disrupted, for example by a collision with another object. You are quite dismissive of Newton’s Cannonball. It seems as it stands that we hold different beliefs regarding these basic laws of physics and their simple applications. Whereas you wholesale disregard them, I do not, and so am at odds to discuss something you state is false, especially because NASA has discussed it. A patient, methodical approach is required in approaching anything in science and engineering. Isolated facts on their own paint an incomplete picture of reality.
As well as viewing rocketry possible in a vacuum, the existence of satellites is also something I believe to be true. Many universities with physics and engineering departments have teams building economically feasible mini-satellites, which may weigh as little as 1-10 kg. In fact I visited such a university (Surrey). The relative difficulty in launching a rocket due to legal issues relate to airspace security for a country as well as for airliners. Otherwise it’s perfectly possible for a group of people to save money to spend on a satellite which is part of a rocket payload. Within a matter of hours this small satellite will be transmitting data back to us. This is the site https://www.surrey.ac.uk/surrey-space-centre....thousands of man-made machines are currently revolving at hypersonic speeds around Earth...
As for the ISS I am indifferent to it. It represents a crass expenditure of wealth and may well be a fabrication. My interests lie with what’s more practical. And robotic space research is cheaper and less "Hollywood". I highly recommend members of this forum to check out mini-satellites and how you can get involved.
Here is one of the cruxes of the debate. Pushing against air may be important for a bird or a plane etc., but not for a rocket for the numerous reasons outlined above. A rocket, take for example a firework, most strikingly lacks wings. Instead its shape is reminiscent of a spear forcing air out of the way, piercing through it (notice how simple fireworks generally take a curved flight path). Inside a whole slew of gunpowder substitutes and what-not are ignited by a fuse. And the products of combustion are forced out a tiny hole, pushing upwards against the rocket. As you might have guessed, the rocket pushes downwards on the exhaust products, and visibly the firework soars upwards.without the need to push against air (which is, of course, the primary force that propels any man-made rockets / or fireworks within our atmosphere).
Patrix, thank you for your in-depth response. I feel much of my reply already has material relating to it. So to add to it, rockets do not rely on the presence of air to propel themselves. I’m afraid it cannot be distilled any simpler than this, other than to use simple models in experiments to show for it.
Ironically Kickstone’s posts clearly support what I am talking about. A pressurised hobby water rocket, let’s say 20 meters above ground with a solid stream of water being expelled, is not moving due to the water’s interaction with the air around it. Water is stable in air. Clearly it’s the opposite forces acting within the bottle causing it to fly upwards.
Thanks for the reply Flabbergasted.
It may appear I am speaking on my own authority, but as I said earlier, these are easily verifiable facts in the public domain. NASA is not a hydra yet capable of twisting knowledge in the public domain- slimy people and corporations mostly excel in fake media. I have read Simon’s posts and they are inconsistent with basic scientific principles, especially when the laws of Physics have been disregarded, they are not points to be easily debated with as I’ll have to enter a playing field where the ordinary laws of the universe no longer work.
As for a rocket hovering over a launchpad, if one assumes that the exhaust is not pushing against anything, then this goes against the other assumption that it pushes against air. So this point too is uncertain in how it was reached.
Can Newton’s Laws be applied to a rocket in space? Well the nature of space much be understood first, as well as the important Laws of Physics too! Primary experimentation and seeking the help of a professor unaffiliated with NASA can seriously help here. If my reasoning and stating or facts seems circular, then I’m afraid that the only recourse is a secure, formal lesson from a professor who is happy to demonstrate from first principles all the physics being discussed here.
Cluesforum is jumping into topics with insufficient knowledge to approach them with. Now this shouldn’t be a problem, as self-learning is an important skill. Yet you need at some point external tutelage to amend the errors, lest disordered analysis is applied to the tearing apart of media fakery. I’m merely a student more concerned with electricity and power rather than mechanics, yet these are topics that I too have covered in school and still study now.
The arbiters of media fakery do not play by the rules, and it is for this reason they are more likely to be found peddling fiction where disbelief is suspended i.e. in films, news, and TV etc; they may be able to use rockets to launch satellites, but the crass ISS images rely on the suspension of disbelief. It is though the TV that they relayed the totally impossible 9/11 fraud.
My reply has become rather long. I hope that it sufficiently responds to points raised by you fellow researchers, and I gladly anticipate responses to it. I have tried to remain courteous, and this is a personal principle that is inviolable; no matter how much you may disagree with somebody, to become agitated only serves to cloud ones logic and lead to bad decisions being made. Impatience breeds discord, whereas sincere interest in finding the truth builds strong bonds.