Umboi: Did Rays Evolve The Ability To Fly?

They aren't saying a three tonne ray could fly. BUT they are guilty of attacking someone for seemingly trying to keep a debate based in fact, based upon evidence.

Also, three 'A' levels doesn't make you a marine biologist. A degree would do that, 'A' levels would be the entry to the degree course, but if;

"there are other equally qualified marine biologists who have radically different opinions to him."

Let's hear from them shall we? Please go dig up a qualified marine biologist who can demonstrate your claims about 6metre rays learning to fly and being responsible for 'ropen' sightings. That is what you are saying, yes?

 

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When I read that last post it started coming out in the voice of Stewie (family guy). Very funny.

 

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And when I read your post I started thinking "He's avoiding any and all criticisms because he's unable to back up his claims or accept he is wrong". Unfortunately its not funny, it's just pathetic.

 

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Got a mechanism for a 'light ray' to be viable yet?

Or for a floppy, three tonnes ray to be able to mechanically support itself and direct lift to it's c.o.m. ?

Anything to make the numbers anywhere near feasible?

Please stop wasting opportunities to respond with diversionary 'Family Guy' crap.

There are technical questions you should be answering. Answer them or admit you're a bullshitter.

 

Listen you ****ing idiot, as has been explained to you repeatedly who you were refering to is irrelevant. We want a full, detailed, technical explanation of the 'basic' mistake you claim phlog made. You have not provided this.

That was not an explanation of any substance, value or relevance.

Your opinion is irrelevant. We require evidence, facts, maths and an exposition (in detail) with the maths of your detailed aerodynamic knowledge.

It doesn't have a lifting body.

You are ****ing turkey. You are in serious violation of forum requirements to provide justification for claims. You are in even more serious violation of regulations against attempting to impersonate an intelligent human.

 

DENSITY.

I keep saying it. You keep NOT answering, or understanding. For a ray to swim, it's body tissue must be at the same density as water, so it can move freely. If you make it lighter, that can only be at the cost of it's size.

IF your ray became lighter, through lessening it's DENSITY it would not be able to dive, making it a useless sea creature. That lessening of weight will not significantly aid it to fly. It would be rubbish at flying, and no longer able to swim. You have created in your mind a non-viable species, a dead end in evolution. For mutations to be passed on, they need to be at least non-detrimental, and you have a detrimental mutation here.

Oh, and your statement "Does anyone have a valid argument why a small ray couldn't" isn't valid. It's your hypothesis, it's up to you to demonstrate it COULD happen.

Why a 'small' ray, btw,... that isn't going to satisfy your 6 metre wingspan requirement. See, you have this problem, you now seem to accept a large ray isn't ever going to fly, and have retreated to trying to prove a small one might be capable. But the density problem still applies. You need to propose a solution to that. Flying fish conquered it by not having fleshy fins, and by adopting the silhouette of a bird, ... do you not see that the natural body plan for flying creatures is like a bird yet?

 

1. Long slender wing is so often seen in artifactual (man-made) flight for a very important aerodynamic reason. Since the wing tips are a small percent of the entire wing, tip loss ruins only a small part of the entire potential wing lift. Wing tips are terrible aerodynamic enemy of lift. You ever notice "rudders" on wing tips of airliners? They are effort to prevent some of tip loss. Tip loss produces no lift but still produce plenty of drag.

2. Delta wing or similar planform has terrible low speed lift/ drag characteristics. At low speed delta wing must be operated at high angle of attack to get lift. High angle of attack makes big amount of drag. WAG guess of your imagined ray flight speed might be 20 MPH? At 20 MPH a delta wing man-made airplane would have to have nose high in air at stall angle with high amount of propulsion power to overcome drag. Look up old newsreel movie of F102 or F4D Skyray or Concorde in take off or landing. I think I remember scene of F102 landing in old movie Strategic Air Command starring James Stewart. Delta shape is superior in several constraints only at speeds far higher than any animal is capable of bodily producing. F4D takes off at 120 MPH with 16,000 horsepower in AB MAX.

3. Largest ray on record is about 18 feet wing span with sharply tapered planform. Area best I can calculate from photo about 100 square feet. Innermost half of span would have Reynolds Number based on wing chord favorable to man-made aviation (jet fighter, airliner, such like). Outer half of wing span would have terrible Reynolds Number (also referred to when speaking of scale effect). So lift of ray wing is terrible because of double whammy of unrequited tip loss, and bad Reynolds Number (or if you like scale effect) of half of wing.

4. Imaginary flight of ray is like any bird. or like butterfly. Gliding with immobile wing has wing flat all time making lift all time. Flapping wing for propulsion reduces lift duty cycle of wing. Flapping wing makes lift only "half" of time. Rest of time wing in ornithopter motion is wrong geometry for lift so it can make propulsive thrust.

5. So, lift of ray wing is "half" of regular airplane lift per square foot because of large tip loss endemic to delta shape.

6. Lift of ray wing loses another factor of "half" because of bad Reynolds Number (scale effect) of half of wing span.

7. Lift of flapping ray wing loses another factor of "half" because of loss of lift duty cycle.

8. Lift of wing is proportional function of speed. This is part of Reynolds Number, or, if you wish, scale effect. At 120 MPH F4D Skyray wing supports 45 pounds per square foot of wing area. At 20 MPH, after taking into account all of the "halfs" you would be very lucky to support something like 5 pounds per square foot of record size ray wing. Not much more.

9. Smaller ray, like one or two yards wing span: bad mojo of smaller Reynolds Number (scale effect) gets badder and badder. Very optimistically cut lift down by only one or two "half" more.

10. Model aviation is very thoroughly familiar with airplanes of one or two yards span and of every planform imaginable. To reliably take off and land at 20 MPH a two yard span delta wing would be wing loaded at something like 1 pound per square foot max. Find model airplane enthusiast and study how lightly built, compared to bone and skin, small flying models are built. They are flimsy as hell compared to a ray fish.

11. It has been pointed out that flying ray must have stiff body to get center of lift to be at center of gravity. Amen. Rule of thumb is that center of lift is at 25% back from leading edge of average wing chord. So, ray body must be stiff enough, as in heavy, to be structurally sound.

So, if you can map out a satisfactory natural selection change from a creature having 100 square feet and weighing a reported 5,000 pounds (50 pounds per square foot) to one with with a wing loading of something like 1 to 5 pounds per square foot, you can get your theory out of the starting gate.

I'm not very enthusiastic about the success of your concept.

 

So why is the shape of a fruit bat's wings make it a better flyer than a bird, then? Batsb aren't renowned for their long and slender wing design.

The ray doesn't have a delta wing anyway.

Man-made aviation calculations don't apply to organic flexible wing structures. The ray has a complex muscle system (with specialised ligaments if necessary) which can form dynamic undulation shapes of the body; analagous to wafting a sheet up and down to create forward motion.

Again, you are using wing-flapping of a bird and assuming manta ray wing dynamics is the same. It clearly isn't.

. BS. It isn't even delta shaped.

You need to convince me more on this one.

For a bird flapping motion perhaps.

Not convinced at all.

not convinced.

BS. The German 'ray shape' model aircraft was particularly stiff and robust, weighing next-to-nothing. You're definitely wrong on this one.

BS. You're too readily applying stiffness to weight. Again using man-made calculations.

I'm not very enthusiastic about your credentials to make such an assessment.

 

So its okay for you to have healthy skepticism for other people's claims but when you make a claim about UFOs being explained as flying mythical creatures or the centre of the Sun not being baryonic matter you don't have to provide evidence?!

More hypocrisy! You claim to have done astronomy and aeronautics yet you're ignorant of basic facts in those areas and seem completely unfamiliar with the scientific method.

Furthermore you ignore the comments, explanations and criticisms by people who have much more experience than you provide. I have superior credentials to you in the realms of gravity or quantum mechanics yet you ignore anything I say to you about how your claims don't square up with experiments.

Cranks often display this mentality. They say mainstream science must be questioned, that people need an open mind but when someone questions their work suddenly its "You should be accepting my theory without question!!".

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It's like the Creationist "Competing ideas hsould be taught along side evolution!" but when pressed they don't mean Islam and Judaism or the Flying Spaghetti Monster, they mean Christianity and only Christianity. Cranks are only open minded so much as they want people to accept their claims.

 

One last thing to mention; the German 'ray-shaped' model aircraft made superb turns without loss of altitude (due to the highly curved design). Therefore, when someone actually has practical experience of this type of dynamic, they can imagine that a gliding ray could out-manouevre a predator by doing a simple U-turn above the waves.

There was a recent TV nature documentary which showed a crab-eating antarctic seal escaping the onslaught of a pod of orcas by sticking close to a small iceberg. Agility can outwit even these formidable foes.

 

That someone obviously isn't you.

I have asked you repeatedly to explain why you don't have to justify you claims while you won't accept anyone else's comments unless they are justified.

If you had done aeronautics you'd know that the only thing relating the plane you speak of and a manta ray is the generic shape. Planes have much more thrust and are fine tuned to fly in air, a medium they are much denser than. Manta rays have very little thrust and they have evolved to fly in water, a medium about the same density as them.

The plane makes agile turns in air because its got a huge amount of lift coming from its wings and thus can use control surfaces to turn. A 3 ton manta ray in the air is about as aerodynamically agile as a Ford transit van!

If you think otherwise JUSTIFY YOURSELF.

 

You are obviously seriously confused about me.

I do not care if you have a good opinion or bad opinion about me. I do not care if you have any opinion about me.

You have me confused with somebody else who you imagine cares what you think about them. It aint me babe. I dont give a flying shit what you or anybody else on this site thinks about me personally. Every time I make a post I am on the thin edge of offending somebody with enough clout to beam me up out of here. If I choose to make a post I just tell it like it is, in my humble opinion. Take it or leave it or ban me again.

I have given you free of charge pretty good critique of aerodynamic aspect of your interesting concept. If it had not been interesting I would not have let it catch my interest. Duuh. Everything I posted is solidly in ball park. Everything I posted adds up to cast serious doubt on your concept. I dont care one way or other about you personally. I gave honest critique of your concept to best of my admittedly meagre ability.

What you should do is to thoughtfully study each point of my critique. Get a big piece of paper and each time my comment bothers you make a note of it. Then later carefully study each point. When I am wrong, :bugeye:, then write out your thoroughly detailed defense of that point. Not because you want to combat me, but, because some other nutter might say the same thing about your theory again later, and you will already have your defense ready.

Since my comments are all based solidly on established aerodynamic science and technology, if you disagree with one, you really should thoroughly investigate that particular sector of aerodynamics. I am assuredly not the only person with some specific knowledge of aerodynamics who is going to raise the same issue(s) as I have raised. UH is not some kind of unique individual barrier to success of your concept. The entire body of the well established science of aerodynamics is a seemingly serious barrier to the success of your concept.

 

And Ophiolite's award for Best Justified Put Down of the Year goes to.......

 

What other kinds of calculations are there? I don't see any other creatures expressing things with math. :facepalm:

Seriously, for the health of others on this board, you might want to lower your woo level a bit. I'm worried that if you continue to vomit out all of this super-woo, you going to make Ophiolite pop a fuse upstairs or something.

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Manta rays don't have bones, they use thick, heavy cartilage. It's not supported by anything rigid. see:

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Where as things that actually fly like this fish eagle:

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or this bat:

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Have thin, hollow bones to support their wings. Rays just don't have this. They don't need it. Their bodies are neutrally-buoyant in the water, so their "wings" don't have to support the weight of the body, or provide any lift. They just have to propel the ray through the water. Once out the water, though, the body is no longer neutrally buoyant, and its wings would have to support the weight of it's body, and provide lift to overcome the force of gravity. Wings made of cartilage wouldn't be rigid enough to support the weight.

 

I see you have been boning up on the theory.

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Imagine the turning circle on this baby! Any danger and it jumps out of the water and does a 180 on a dime!

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Then promptly sinks.

 

Who said Fruitbats were better than which birds? You have made a specific comparison on one side to a generic one on the other, ... what type of bird are you comparing your fruitbat to? Also, if you compare the width and length of a bat's wings, and calculate a ratio, ... guess what, ... you are wrong, again.

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That doesn't qualify as a delta shape? Yes it does, guess what, .. you are wrong.

Yes they do, guess, what, you are wrong. Aerodynamics applies to everything that flies, period.

In water.

Clearly it isn't, Uno was being gracious and envisaging a ray flying using a flapping motion. Now you are back peddling and saying it 'undulates' to provide lift for it's THREE TONNE bodyweight?

I refer you to the picture above. It's clearly delta shaped, and guess what, you are wrong.

Uno has provided sound aeronautical reasons. If facts don't convince you, you are beyond hope. Google Reynolds number, read learn, and come back with a QUANTITATIVE criticism.

So now your ray 'undulates' but you have no numbers.

It's true, faster speed = more air over wing = more lift. What don't you grasp about that?

OK, so comprehension is your problem. Uno was saying that model aircraft are stiff and light, and you DISAGREED with him, saying model aircraft are stiff and light. READ WHAT PEOPLE WRITE and STOP BEING SO KEEN TO PICK A FIGHT BECAUSE IT MAKES YOU LOOK STUPID.

And a large manta ray weighing a couple of tonnes requires what branch of mathematics, ... ? Stop showing your ignorance, please.

It's clear Uno has a sound grasp of Aeronautics. It's clear you have a slender grasp on reality.

 

Common_sense_seeker's body is aerodynamically designed in a way for him to fly, the low drag of his body comes from the small head and the arms act as wings with extra large hair body acting as feathers, but wait...he directly evolved from the sea rays that were interdimensionally teleporting in and out. in and out, period.

 

It slowly stacks its prey of many diesel powered motorbikes and goes for the kill.