Scientists and Engineers Who Thought Heavier Than Air Flying Machines Were Impossible

[Mojo]

Perhaps it's manned flight, but I would have thought that Stringfellow would have had a go with that too.

Not powered, but Sir George Cayley flew his coachman across a valley in a glider in the early 1850s. The coachman resigned.

But here are two powered, manned machines that predate Kelvin's statement:

Clément Ader's steam-powered Eole managed a hop of about 50 yards in 1890 (the first manned aircraft to take off under its own power) but had no real means of control; in 1897 a later plane of his either flew 300 yards or crashed before take-off, depending on which witnesses you believe.

In 1894 Hiram Maxim tested a three and a half ton flying machine powered by two steam engines on a track which prevented it from leaving the ground but showed it generated enough lift to do so. It probably wasn't stable or controllable, but showed that flight was at least possible. His mousetrap was a more successful invention.

 

[Mojo]

Unfortunately the Wright Brothers get the popular credit when really Stringfellow should.

The important thing that the Wright brothers achieved was manned, powered, controlled flight.

 

[Rodney]

Now that I've debunked the Lord Kelvin thing, I have to consider someone else?

I don't understand what you're driving at. Sure, many people were skeptical about powered flight. They had good reason to be - after all, people had been trying and failing to achieve it for millenia.

So what?

The point of my last post was that, in 1903 -- several years after Langley had developed his flying machine -- Newcomb and the NY Times expressed skepticism as to whether he had proven that man could truly fly; i.e., fly in a controlled manner. So, your notion that Lord Kelvin would not have said in 1895 that heavier than air flying machines are impossible does not follow. I agree, however, that we need to pin down exactly what Kelvin said and in what context.

 

[mhaze]

Not quite. John Stringfellow achieved the first powered flight in 1848 in Chard, Somerset, UK.

http://www.flyingmachines.org/strng.html


http://www.chardmuseum.co.uk/Powered_Flight/

He was right and the Wright Brothers use of a combustion engine allowed this, however, heavier than air powered flight had already been demonstrated to a wide audience. I would have thought that Lord Kelvin would have been aware of this milestone. Unfortunately the Wright Brothers get the popular credit when really Stringfellow should. Perhaps it's manned flight, but I would have thought that Stringfellow would have had a go with that too.

Looking at your links, I'd have to disagree. Stringfellow launched the 10' wingspan, 6+ lb. machine from a wire after imparting momentum to it, and it went 30 feet. No evidence of any active propulsion there. A flight of 30 feet or 3x wingspan can't be said to be powered flight when launched with kinetic energy.

Without even calculating it, it's clear that the energy output of a candle (transmitted through a steam engine) isn't enough to move over 6 lb. level against gravity or climbing.

Also, there were IIRC rubber band powered flying toys going back considerably farther than this. Were they "powered aircraft?"

 

[ponderingturtle]

Since birds are heavier than air, I can't imagine how anyone observant could have concluded that such machines are impossible. Maybe they thought angelic assistance or a pinch of pixie dust was necessary?

Such statements are about the fesability of engineering not the laws of physics. And as such scientists are not the best ones to voice what is not possible to engineer.

 

[Just thinking]

Bah! According to this guy, we don't even know how wings really work...

Has this guy ever gone to flight training? I doubt it, because one of the first things one learns is that the shape of the wing is not the only characteristic of the wing enabling flight. There is this little thing known as attack, meaning the angle at which the wing confronts the air. Both are crucial in accomplishing lift in a fixed wing aircraft --- and it's the attack of the wing which allows a plane to fly inverted, to the point of overcoming the shape's natural tendency to provide lift in the opposite direction, e.g.; downward. I'm not saying he's completely wrong on the speed of the air relative to the wing, but as for flight instructors not teaching as to how a wing provides lift, he's certainly in the dark. It's one of the first things I was taught when I learned to fly.

 

[mhaze]

Bah! According to this guy, we don't even know how wings really work...

Pretty funny. But in between laughs I've got to say that it isn't even worth watching and he knows nothing. At the point where he says "I don't have access to a wind tunnel and don't know anyone that does but if you know anyone who knows anyone who knows anyone who does..."

Apparently he does not know that 2 dimensional airfoil analysis programs are widely available either java based or to run on your pc. Well, if anyone wants to I'll go through his talk point by point....

Let's put it this way, the mid and late 19th century engineers, scientists and laypersons who struggled to solve the riddle of flight were way ahead of this 21st century loon.

 

[Chris Haynes]

Bah! According to this guy, we don't even know how wings really work...

Has this guy ever gone to flight training? ... .

Pretty funny. But in between laughs I've got to say that it isn't even worth watching and he knows nothing. ....Let's put it this way, the mid and late 19th century engineers, scientists and laypersons who struggled to solve the riddle of flight were way ahead of this 21st century loon.

Okay, a disclaimer here: I have a BS degree in aeronautics and astronautics engineering, but I have been a stay-at-home mom for almost 20 years (something to do with giving birth to a disabled kid).

PLUS I skipped through most of his rant after he said "what they don't tell you in astrophysics or flight training...", because I knew from then on the guy did not know anything about what he was talking about. Even though I hated thermodynamics, fluid dynamics and aerodynamics (I worked in structural dynamics).... I do know the basics of lift in relationship to wing geometry: this guy is completely clueless on those subjects.

Rodney, learn a bit about the history of aerodynamics, please!

Get yourself a copy of Introduction of Flight, by John Anderson (oh, wow... look at the prices! ummm... check it out of your local library instead). I have in front of me the 1978 edition I used in my first aerodynamics engineering class (which only has 430 pages, not the 836 pages of the one at Amazon). Not only does it have the basics of aerodynamics, but some very important highlights in history of heavier than air flight. Dr. Anderson has several essays on that subject in the book. Not surprising, since he is also the curator of aerodynamics for the National Air and Space Museum.

 

[Chris Haynes]

Wilbur Wright, 1901: "Man will not fly for a thousand years!"


Of course, he wasn't a household name, then. Does it still count?

... Introduction of Flight, by John Anderson ....

The Wright quote is on Page 1 of that referenced book. It is in my 1978 edition, and if you go to the Amazon page, it is in the part you can click on to see in the huge version.

 

[Sunstealer]

Looking at your links, I'd have to disagree. Stringfellow launched the 10' wingspan, 6+ lb. machine from a wire after imparting momentum to it, and it went 30 feet. No evidence of any active propulsion there. A flight of 30 feet or 3x wingspan can't be said to be powered flight when launched with kinetic energy.

Without even calculating it, it's clear that the energy output of a candle (transmitted through a steam engine) isn't enough to move over 6 lb. level against gravity or climbing.

Also, there were IIRC rubber band powered flying toys going back considerably farther than this. Were they "powered aircraft?"

If you read a bit more closely you will see that the wire was used as a guide and steam power was used to propel the aircraft which then rose once it had left the guide wire. There is plenty of information on the web and Rolls in Bristol had a replica when I worked there- see next link.

The first flights in 1848 were actually inside a lace mill so as it would not be disturbed by wind.
Eventually the aircraft flew 10 feet unaided and showed that heavier than air machines could take to the air.

http://news.bbc.co.uk/1/hi/england/1591057.stm

There seems to be a lot of contention over firsts on this subject.
http://en.wikipedia.org/wiki/First_flying_machine

 

[mhaze]

Get yourself a copy of Introduction of Flight, by John Anderson (oh, wow... look at the prices! ummm... check it out of your local library instead). I have in front of me the 1978 edition I used in my first aerodynamics engineering class (which only has 430 pages, not the 836 pages of the one at Amazon). Not only does it have the basics of aerodynamics, but some very important highlights in history of heavier than air flight. Dr. Anderson has several essays on that subject in the book. Not surprising, since he is also the curator of aerodynamics for the National Air and Space Museum.

Didn't know that. Only knew Anderson is a very, very good book. Mine has 560 pages.

 

[mhaze]

If you read a bit more closely you will see that the wire was used as a guide and steam power was used to propel the aircraft which then rose once it had left the guide wire. There is plenty of information on the web and Rolls in Bristol had a replica when I worked there- see next link.

http://news.bbc.co.uk/1/hi/england/1591057.stm

There seems to be a lot of contention over firsts on this subject.
http://en.wikipedia.org/wiki/First_flying_machine

As Hydrogen Cyanide, I have to explain that I do know this subject professionally. Actually I read carefully about the guide wire and the use of steam power. So I'm taking that into account. A bit more explanation -

1. The model had momentum when it left the wire.
2. The momentum carried it forward.
3. Some unknown amount of thrust was also provided by the steam engine powered by the candle.
4. The model went 30 feet.

Analysis.

Initial energy components:

Height above ground at time of launch.
Momentum at time of leaving wire.
​

Energy during flight:

From steam engine powering two propellers.
​

Unknown:

The height at launch
Amount of momentum at the time of leaving the wire
Amount of thrust from the props
​

Known:

It went forward 30 feet or 3x the wingspan.
​

Question: Did the 30 feet of forward movement constitute powered flight?

Answer: No.

Reasons.

Any of a number of gliders would go 30 feet forward in the conditions described. Assume the wire was 6' above the ground, this only represents dropping one foot for five feet forward. Ten to one might have been expected for a 19th century glider (not sure we have any data on this) and today of course we do way, way better. If 1:5 is presumed then for level flight you need 6 lb/5 or 1.2 lb thrust; if 1:10 is presumed you need 0.6 lb thrust.

Powered flight occurs when an aircraft by using thrust can stay in level flight against the force of gravity. Thirty feet or 3x wingspan is clearly insufficient for such a demonstration, especially given the potential and kinetic pre existing energy components. A hundred or two hundred feet would be sufficient BUT:

For that short flight one would only have demonstrated flight in ground effect, which takes considerably less energy than actual flight.

As I mentioned, taking an estimate of the possible efficiency of the propulsion system and looking at it's input power would obviously disprove "flight". EG, what energy does it take to move a 6 pound thing? Did the steam engine at typical efficiencies (1-8%) for the power input produce 0.6-1.2 lb thrust?

 

[Rodney]

Rodney, learn a bit about the history of aerodynamics, please!

Probably a good idea, but I'm not the guy in the You Tube video.

 

[robinson]

Yeah, but the YT video was such a great Stawman, you got tarred with the same brush.

 

[TjW]

The point of my last post was that, in 1903 -- several years after Langley had developed his flying machine -- Newcomb and the NY Times expressed skepticism as to whether he had proven that man could truly fly; i.e., fly in a controlled manner. So, your notion that Lord Kelvin would not have said in 1895 that heavier than air flying machines are impossible does not follow. I agree, however, that we need to pin down exactly what Kelvin said and in what context.

Do you have any quotes from distinguished scientists expressing skepticism about the possibility of powered human flight after 1908, when Wilbur made the demonstration flights in France?

Langely's aerodynamic work was very sloppy. Frustration from relying on some of his research for the 1901 glider is at least partly what led to Wilbur's quote.

 

[Chris Haynes]

As Hydrogen Cyanide, I have to explain that I do know this subject professionally. ....

No, you are not my sock-puppet! I think mhaze was saying "Just like Hydrogen Cyanide".

Plus, I only know about the stuff, I have not had to do Power Required versus Power Available envelopes for several decades! I really hate thermodynamics, fluid dynamics and aerodynamics.

 

[Chris Haynes]

Probably a good idea, but I'm not the guy in the You Tube video.

I know that... but since it has been pointed out that you've assumed wrong information about the history of flight multiple times, you still need to check out the book.

 

[mhaze]

Ok, I'm going to do it one better (worse) than Rodney. Remember the Coanda effect, and the alternative theory of lift eg rotating circulation around a 2 dimensional cross section of the wing? This was used with extensive experimentation of upper surface laminar flow in this project:

http://www.youtube.com/watch?v=YRrzcnBPpm4

I think that link should lead to various videos. Long and short of this is ....

WE NOW HAVE FLYING SAUCERS!

YOU TOO CAN HAVE YOUR OWN FLYING SAUCER!

Scaling. Looks like up to 8' might work. Now how weird is that?

 

[Rodney]

I know that... but since it has been pointed out that you've assumed wrong information about the history of flight multiple times, you still need to check out the book.

What wrong information have I assumed? I have documented that, shortly before the Wright Brothers made their historic December 17, 1903 flight, both Simon Newcomb and the NY Times were expressing skepticism about the feasibility of heavier than air flying machines. Further, I have documented that more than a year AFTER that and subsequent Wright Brothers flights, Scientific American expressed skepticism as to whether those flights had actually happened. So, that leaves Lord Kelvin's alleged 1895 quote that "heavier than air flying machines are impossible." I am still trying to pin down exactly what he said and in what context, but does it really strike you as unlikely that he might have made that statement a decade BEFORE Scientific American asked whether it was "possible to believe that the enterprising American reporter . . . would not have ascertained all about them [Wright Brothers' flights] and published them broadcast long ago?"

 

[TjW]

What wrong information have I assumed? I have documented that, shortly before the Wright Brothers made their historic December 17, 1903 flight, both Simon Newcomb and the NY Times were expressing skepticism about the feasibility of heavier than air flying machines. Further, I have documented that more than a year AFTER that and subsequent Wright Brothers flights, Scientific American expressed skepticism as to whether those flights had actually happened. So, that leaves Lord Kelvin's alleged 1895 quote that "heavier than air flying machines are impossible." I am still trying to pin down exactly what he said and in what context, but does it really strike you as unlikely that he might have made that statement a decade BEFORE Scientific American asked whether it was "possible to believe that the enterprising American reporter . . . would not have ascertained all about them [Wright Brothers' flights] and published them broadcast long ago?"

I think both Newcomb and the Times were commenting on current events. On October 7th, and again on December 8th, Langley's "Aerodrome" had just made a big splash both in the newspapers and the Potomac.
If there was some skepticism after a recognized expert such as Langley had failed so spectacularly, I don't find that too odd.

As for Scientific American, the Wrights were not giving demonstrations in 1904. They had not yet received their patent on the control system, and were concerned about anything which might be construed as disclosure regarding their invention.