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Messages - DuncanDoenitz

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Science & Alternative Science / Re: Do rockets push off the air?
« on: December 08, 2023, 02:42:06 PM »
Whilst I echo Dr V-N's sentiments (and call me Mr Cynical) I am curious to what extent A80's nephew is on-board with this idea.  ("My uncle said what"?).  I mean, can we get an outline of how the conversation went?  Did you come up with the theory, or did you get it from  him?  When did you last discuss it?  After all, we only have your assertion that he is in agreement. 

As for General Electric and Pratt & Whitney being on the same page, without any references, this adds a whole 'nother stage of incredulity. 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 08, 2023, 02:06:10 PM »

So, all internal...

And yet all the arrows in Figure 1-1 show the exhaust traveling to to the rear.

If it truly was all internal, then the thrust would be traveling to the front, like some other jokers like to claim here.

Got the correction; thanks.  This is a simplified diagram of the gas flow through the engine; it does not illustrate thrust.  It shows air being inducted from the left, compressed and impelled centrifugally by the compressor, diffused and entering the combustion chamber (to the right), passing though the turbine and exiting (to the right).  (Incidentally, the fact that the intake is to the left is just a convenience.  Many engines draw their air from all around, it doesn't matter.  The only important vector is that exhaust goes right, reactive thrust goes left). 

It is a simplified diagram is explaining the gas path.  To the target audience, the fact that thrust acts to the left does not require explanation.  Why would any of the arrows point left? 

An equivalent diagram for a road vehicle might show the engine, pistons, transmission and wheels going round.  The fact that the wheels try to push the road backwards does not need to be explained. 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 08, 2023, 09:36:00 AM »
Exhaust gas accelerates right.  Reaction applies a force left.  Force pair.  Can you specify where the RR Book denies this? 

And going back a couple of posts, can you clarify you meant Fig 1.5?  That's a garden sprinkler. 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 08, 2023, 08:29:26 AM »

It doesn't matter what your source claims, there is a plume related to all jets and rockets (i.e., we see what is typically called a contrail), and that plume reacts with the pressurized external environment to form a force pair, which results in movement. No force pair, no movement.

The "source" which designs, develops and manufactures jet engines, refuted by Action80's superior insight.  And possibly his nephew. 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 07, 2023, 11:20:13 PM »
Yes, I have and he understands that a pressurized environment must exist for a plume to form.

Do his superiors and the engineers that designed the equipment he works on understand it?
Of course they do.

If he were to ask the people who trained him about rockets and vacuums what would they say?
Pretty much the same thing I am.

Are you smarter than them or are they lying to hide the truth?
Lying about what?

You have an admirable confidence that:
a.   You have understood what your nephew means, and vice versa.
b.   You nephew has fully understood what he has been taught. 
c.   The jet engine designers, engineers and technicians are also in accordance with you. 


This is a link to a pdf version of a go-to publication in the UK, and also much of the English-speaking world.  It is called "The Jet Engine" (ISBN 0 902121 2 35) and its published by Rolls Royce, who know a couple of things about them.  The book is standard reading for anyone in the UK who is embarking on a career in aircraft engines.  It outlines the principles of theory, design, construction and maintnenane, and not just of Rolls Royce products. 

I draw your attention to Part 1 "Basic mechanics", page 2, Paras 6 thru 9:

6. Jet propulsion is a practical application of Sir
Isaac Newton's third law of motion which states that,
'for every force acting on a body there is an opposite
and equal reaction'. For aircraft propulsion, the 'body'
is atmospheric air that is caused to accelerate as it
passes through the engine. The force required to
give this acceleration has an equal effect in the
opposite direction acting on the apparatus producing
the acceleration. A jet engine produces thrust in a
similar way to the engine/propeller combination. Both
propel the aircraft by thrusting a large weight of air
backwards (fig. 1-3), one in the form of a large air
slipstream at comparatively low speed and the other
in the form of a jet of gas at very high speed.
7. This same principle of reaction occurs in all forms
of movement and has been usefully applied in many
ways. The earliest known example of jet reaction is
that of Hero's engine (fig. 1-4) produced as a toy in
120 B.C. This toy showed how the momentum of
steam issuing from a number of jets could impart an
equal and opposite reaction to the jets themselves,
thus causing the engine to revolve.
8. The familiar whirling garden sprinkler (fig. 1-5) is
a more practical example of this principle, for the
mechanism rotates by virtue of the reaction to the
water jets. The high pressure jets of modern firefighting equipment are an example of 'jet reaction',
for often, due to the reaction of the water jet, the hose
cannot be held or controlled by one fireman. Perhaps
the simplest illustration of this principle is afforded by
the carnival balloon which, when the air or gas is
released, rushes rapidly away in the direction
opposite to the jet.
9. Jet reaction is definitely an internal phenomenon
and does not, as is frequently assumed, result from
the pressure of the jet on the atmosphere.
In fact, the
jet propulsion engine, whether rocket, athodyd, or
turbo-jet, is a piece of apparatus designed to
accelerate a stream of air or gas and to expel it at
high velocity. There are, of course, a number of ways .....

I can find no mention of "plume" in the book, but be my guest.  Perhaps you could discuss this further with your nephew. 

Edit; my Bold, btw.

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 07, 2023, 08:39:26 PM »
@Action. First of all respect to your nephew; serving his country in the military and then transferring those learned skills to the airline industry.  Similar career path to mine, though in the UK. 

Following up on Dr v-N, I wonder if you have actually discussed jet engine theory with your nephew, or whether you are just throwing in random relatives in the hope that it will lend your argument some kudos.  My sister is a nurse, but that wouldn't reinforce any argument I might make about Covid. 

And I don't like labouring a point, but you still haven't explained how the presence of a plume lends thrust to the jet/rocket. 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 07, 2023, 05:41:55 PM »
Whether a plume can form in a vacuum or not, can you expand on its relevance to propulsion?  Your opening hypothesis is that a plume somehow imparts movement to the rocket, but you have not explained how this happens; what is the science behind this? 

Science & Alternative Science / Re: Do rockets push off the air?
« on: December 06, 2023, 11:27:36 PM »
I began training as a Jet Engine Engineer in 1969; it was my career. 

I've no idea what the "plume" is that Action80 refers to in respect of a gas turbine engine.  They categorically do not rely on "resistance", or "pushing off the atmosphere", but please don't allow facts to get in the way of a good theory. 

Contrary to its title, "Popular Science" is not a professional scientific journal, it is a digest of scientific articles written for the layman.  The issue in question appears to date from the 1940s, and the article admits that much of the technology discussed is still secret.  The statement that thrust is obtained by a ("monstrous") jet of energy pushing against the atmosphere" is incorrect, as well as employing hyperbole. 

The diagram top-left of the article is false; there is no such component as a "carburation chamber (C)" in a gas turbine engine, nor does it illustrate the turbine. 

And Tom; "They probably move through multiple mechanisms"?  Glad we nailed that. 

Yes, I admit to some embarrassment about posting on an FE forum. 

Anywho, I worked with pilots on a daily basis; not sure where your experience is drawn from.  Good to know you hold them in such high esteem though, as most astronaut pilots are former fighter pilots, 

@ Dual1ty; can I just throw in a critique on the video in Reply #8; the one that "... no one has even attempted to debunk yet"? 

First of all, the credentials of the F-16 pilot.  Yes, if he's an F-16 pilot you would expect him to have appropriate intelligence and education.  I am a retired aircraft engineer/mechanic.  So far as my personal abilities as such are concerned, I would say I did a reasonable job (well I would, wouldn't I)?  Do I remember everything I was taught?  Did I even understand everything I was taught?  Others may differ in their views, but along the way I met some real aces, better trained, more experienced and a broader range of knowledge.  I also met some real duffers; could barely read and understand the manual.  But we were all qualified Engineers.  RonJ, as we know is a Navigator and Engineer.  Is he competent in that job?  Undoubtedly, as he is qualified in that role.  But I bet there are better, and I bet there are worse; a spectrum.  I don't know your career choice, but if you have a field of expertise perhaps you can relate to this. 

The F-16 is one of the most mass produced aircraft currently in service; well over 4000 built, and entered service (in Europe) around 1983.  40 years.  A typical squadron would have 2 or 3 pilots per aircraft, flying the aircraft for perhaps 10 years.  Eight or ten pilots per aircraft, lets call it 40,000 F-16 pilots worldwide; some aces, some not the sharpest knife in the kitchen drawer.  A spectrum.  And this one thinks the world is flat. 

Speed.  Much is made of the 1500mph and "250 miles in 10 minutes".  Horsepoop.  The maximum speed of the F-16 is less than 1400mph, but lets call that within a range of tolerence.  What's important is that the only way an F-16 goes that speed is with a clean aeroplane, no missiles, no external fuel tanks, and for short distances, and not to interecept a bomber.  If he's travelling 250 miles at Mach 2, there better be a friendly airfield at 249 miles.  Interestingly, the accompanying video (which is largely pointless stock footage btw, as you know) does show the USAF Thunderbirds Flight Demonstration Team, with a shot of the cockpit showing us that he's doing 400 kias at 24000', around 430 knots true airspeed, or 500mph.  So 250 miles in around half an hour.  For the pilot, or producer, to suggest otherwise is at least disingenuous. 

The radar.  Our guy assesses that at a range of 80 miles the width of scanstop-to-stop is 138 miles and that should give a hump of 12,700' in the middle of the screen.  Wrong; since the scope either side of the centreline is 69 miles, this would give a real-world hump of just over 3000' on the boresight; less than a mile, at eighty miles.  Insignificant, as any BVR weapon will be targetted by its radar position, not its apparent altitude.  The final line is a cracker, that the radar will get them killed "unless the manufacture has accounted for curvature"!  And?  Is there any evidence that curvature has not been accounted for?  Is that all that's in the drawer? 

Navigating the curvature.  Let me give you an analogy in azimuth.  It took me about 3 minutes on Google Maps to find a highway in Seskatchewan, SK-15, running due west from the town of Nokomis to just short of Broderick, around 80 miles, and its absolutely due west.  So imagine you're driving to Broderick.  Do you set your compass and drive due west from your origin?  No, you drive 2-feet to left of the white line and you arrive in Broderick.  Its absolutely the same with maintaining altitude.  Here we are in the 3rd decade of the 21st Century, and all aircraft maintain altitude, not by GPS, not by radar, not by attitude indication, but by referencing the air pressure.  Doesn't matter if you're on autopilot or flying by hand; pressure increases; the plane needs to fly up.  Pressure decrease; plane needs to fly down.  The pressure of the air is directly related to its height above sea level, and any movement of the aircraft up or down due to curvature is absolutely imperceptable against the other forces, turbulance and changes of mass and CofG as fuel is consumed.  That any pilot can be unaware of this, and state as much, is frankly incredible. 

Science & Alternative Science / Re: NASA’s Latest Moon Actors
« on: September 07, 2023, 08:10:13 AM »
The oldest and best proof of the Earth's flatness can be seen by looking out your window.

And the oldest and best proof of Jimmy Saville's benevolence is to watch his TV shows. 

The idea that a subject can be fully explained by observing it through a 42-inch-diagonal portal is absurd. 

Flat Earth Community / Re: What are you doing here?
« on: September 02, 2023, 11:42:25 AM »
Exactly.  The focal plane ("sensor") is flat; thanks for the unnecessary diagram. 

If you are serious about this, you really need to study optics, opthalmics and camera theory.  Come back and tell us about the roundness of a pin-hole camera for instance, or where is the single point of the human eye through which all the light rays pass (Hint; its not the middle of the oblate spheroid). 

And I don't mean "look something up on You-Tube", I mean actually study the subjects you are "teaching" us about. 

edit; does anyone actually study anything these days?

Flat Earth Community / Re: What are you doing here?
« on: September 02, 2023, 09:51:45 AM »
Yes, round eyes. 

The irony, however, is that every image on this thread was not taken by a round eye-ball, but by a camera. 

A flat, focal plane, camera. 

Science & Alternative Science / Re: Nothing To See Here (Maui)
« on: September 01, 2023, 11:42:29 AM »
Honeycomb and snowflakes in perfect symmetry.  Sine waves.  Remarkable. 

So your latest theory is that the mysterious "They" (Some government?  Thrush?  I don't know, not fully explained) have used the principles alluded to in this video to transform the power of a hurricane and burn some cars.  For some reason.  Why not just have the hurricane wreck the cars in the first place? 

Cui bono? 

Figure it out?  Sorry, need more to go on. 

Flat Earth Community / Re: What are you doing here?
« on: August 30, 2023, 03:06:14 PM »
"It's nonsense because I don't like those facts".

Keep digging lol.

But they aren't facts, are they?  It's just random, unattributed slides from a "write-your-own-science" site on the internet. 


(Obviously, because a post isn't complete without disparaging your antagonists). 

Flat Earth Community / Re: What are you doing here?
« on: August 30, 2023, 02:03:43 PM »
What I just said in my previous comment is 100% fact, by the way. And it 100% debunks the globe.

ONLY globe ZEALOTS will deny it and/or try to misrepresent it.

So, if you are someone who maybe believes in the globe but is not a globe zealot and you are reading this - just think for yourself, look at what I have presented from Google Drive and look at the facts.

This will help you understand it better:

"It's true because I say it is". 

What, exactly, is the relevance or provenance of the Google Drive stuff?  Who wrote it?  Who reviewed it?  It's nonsense.  For instance, in the second clip, the diagram illustrates rays of vision crossing in the middle of the orb of the eye.  They don't; they cross in the lens. 

And what is the relevance of "the curvature of the eye", when reviewing photographs. 

Science & Alternative Science / Re: NASA’s Latest Moon Actors
« on: August 23, 2023, 03:40:26 PM »

How do you know that it crashed on the Moon? Did you get your binos out and saw it?

You have the most cringe-worthy arguments for beliving in heliocentrism.

You're missing my point.  On the basis that no lay-person can observe it, why announce it?  Did it crash?  Did it exist?  Just like you, I've no evidence either way.

The only agencies with the wherewithall to detect its actual presence (or absence) would be the equivalents of Roscosmos in other countries and similar alliances; NASA, EASA, CNSA, etc.  Just like India is experiencing at the moment, a successful mission of this magnitude and complexity is a source of immense kudos and national prestige, both for the home-audience and abroad. 

What is the logic behind Russia mounting this mission (or fake-mission) in the first place, televising its faked-launch, reporting its progress and ultimately announcing its abject failure?  Why not anounce its successful completion?  NASA is never going to snitch, when they are in the same business. 

Science & Alternative Science / Re: NASA’s Latest Moon Actors
« on: August 23, 2023, 02:39:52 PM »
I think more credit is due to Roscosmos.  They're losing a war, Rouble is collapsing, and their only friends on the disc are Belarus, Iran and North Korea. 

Obvious thing to restore credibility to your regime is to fake your spacecraft obliterating itself on the moon. 

ps. "... idiots like you"?  Is that going to stand? 

Flat Earth Theory / Re: FE radius (UAFE estimate)
« on: August 17, 2023, 01:12:58 PM »

You think that Auckland to Santiago de Chile was the most difficult route I had to deal with over the years? No, it was Juneau to Santiago de Chile:

Interesting that you find these routes "difficult".  You didn't actually answer Bob's question about flying Aukland-Santiago did you? 

The reference you provided refers to a flight time Santiago-Sydney, and quotes a flight time of "18 hours .... perfectly compatible with my map".  I guess any flight time would be compatible, since the map does not actually include a scale of distances. 

Historical data on FlightRadar24 suggests that the flight times between the city-pairs Sydney/Santiago are typically 12.5 hours eastbound and 14 hours westbound (against the prevailing wind). 

Getting back to Bob's question, LAN801 is being operated today by Boeing Dreamliner CC-BGR; it left Santiago 7.51 hrs ago, and estimates landing Aukland in 4.09 hrs; exactly 12 hours.  Not only that, but the reciprocal flight, LAN800 is also currently airborne, reg CC-BGA, and estimates a flight time eastbound of 10.5 hours. 

Does all this fit your map? 

.......which is one of the (main) reasons that the Arctic is one of the most restricted areas on Earth.

You keep throwing this out there and expecting people to believe that it's true.  Can you provide any evidence whatever of some World-army or Secret Service keeping people out?  Under who's jurisdiction?  The (unspecified) "government"? 

Alternatively, I contend that "The Islet of Rockall is the Northern True Pole".  Its surrounded by ocean, there are no tourist visits, and I don't know anyone who's been there or even seen it.  Prove me wrong. 

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