General Question

luigirovatti's avatar

Do you agree with the following quote about the classifications of UFOs and so-called "slip flow"?

Asked by luigirovatti (1829points) 1 week ago


“Anything, to be surely classed as a UFO, must meet one of two criteria. Either it has to be seen from a sufficiently short distance to be certain that its configuration is not that of any conventional craft, or its speed, acceleration, or maneuver performance has to be such that no airplane, helicopter, missile, or balloon could possibly account for it. For example, if something goes faster than an airplane, and the same craft slows to a hovering condition, it is a UFO. Even if it goes only 500 mph and also hovers, it is probably a UFO because helicopters can’t go 500 mph. These statements say that range-of-speed capability is more important in the identification of an unconventional object than high speed itself. These criteria tend to eliminate from serious consideration as UFOs meteors as well as objects which are only seen moving slowly at high altitude, especially balloons. It need not eliminate unidentified (usually nonorbiting) objects seen in space by astronomical telescopes, of which there have been a fair number of sightings. These have to be natural objects or spacecraft. Several of the half-dozen or more unidentifieds sighted in space by U.S. astronauts pass the performance criteria; maneuvering in space, or going in a westward orbit as was the green object seen by Gordon Cooper near Perth, Australia, is evidence of superior performance sufficient enough to identify them as unconventional (space) craft, or UFOs.”

Slip flow:

“No discussion of the relief from aerodynamic heating would be complete without some consideration of a phenomenon known as slip flow. According to theory, the air-friction drag and heating of moving vehicles is due to the fact that air molecules cling to any surface; that they cling in clumps, making the surface somewhat rough, makes matters worse. That is why it does no good to polish an aerodynamic surface beyond the point at which the surface proper is smoother than the adsorbed layer of air molecules with its clumps. The clumps contribute to air drag in this manner. A fastmoving air molecule strikes a clump and is stopped, giving up its momentum and kinetic energy. This gives drag plus heating. Molecules leave clumps in random directions, giving no drag alleviation. This process is analogous to diffuse reflection in lighting. Laboratory wind tunnel tests showed that at a combination of low enough pressure and high enough speed and temperature, much of the adsorbed layer of air is knocked off the surface. In this condition the fast moving air molecules can bounce on a smooth surface and reflect off again without losing much energy, in a process analogous to the specular reflection of light from a mirror surface. This desirable operating condition, in which drag and heating are dramatically reduced, is known as slip flow.”

Source: Unconventional Flying Objects” by Paul Hill

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10 Answers

Caravanfan's avatar

No. I do not agree.
There is no such thing as alien spacecraft visiting our planet.

elbanditoroso's avatar

I disagree with @Caravanfan – I am open to the possibility.

But @luigirovatti – my problem with your quotations is who made these rules? Who defined things?

If a person is in charge of an agency that is investigating UFOs, the agency has a vested interest in certain definitions being created in a way that meets their goals.

These are fairly detailed definitions – but where did they come from?

I have a real hard time accepting scientific stuff that has no references that I can examine.

Response moderated
LuckyGuy's avatar

Those are merely definitions and criteria for the narrative that follows.
Given those I can quickly think of a few craft that meet them. The first successful aircraft were biplanes At some point monoplanes took to the air. The person in a biplane would not have been able to identify it.

In WWII when the German fighter jet, Messerschmitt Me 262, took to the skies the Allied were stunned by its performance and operation. They wondered where the propellers were hidden.

Ground hugging cruise missiles baffled radars with its ability follow terrain autonomously.

The B2 Stealth bomber was developed to have a radar cross-section the size of a bird.

All of these would be considered unidentified – until they were identified. That is how technology works.
“Any sufficiently advanced technology is indistinguishable from magic.” A.C. Clarke

Re slip flow. There are ongoing experiments that disrupt the boundary layer by introducing air at leading edges. Super-cavitating torpedoes like the Shkval Va 111 are under development.
Something like that moving in the water would most certainly be considered unidentified.

MrGrimm888's avatar

I don’t agree, with the assessment.

seawulf575's avatar

I have seen objects I could not identify in the night sky. I have seen what many considered a UFO. Event: I was with a friend, sitting at the top of the road talking. Suddenly he said “what is that?” I looked up and saw what looked like 5 or 6 small orange lights in a lopsided vee formation (picture a check mark sitting on its side). They were moving about 100 feet above the trees but there was no obvious object they were attached to. They were moving about 25 mph and there was no motor noise at all. They were following a major street with lots of traffic and street lights so light pollution was a factor. However we watched them move…following the street…for about a mile before they were out of our sight. The next day on the front page of the local newspaper was a picture of these lights. They were reported all along this street for a distance of about 30 miles. The picture was snapped about 10 miles from where I saw them. The government denied having any aircraft in the area. And this was well before the time of drones.
This was an Unidentified Flying Object. Does that mean it was an object from an alien life form from outer space? No. It could be something from someone on earth that whoever was controlling it doesn’t want to admit it. But it is a UFO.
I think the definitions given in the question are a bit wordy. And I disagree with the part excluding things that are out in space. The fact we can’t identify something pretty much makes it a UFO.

Response moderated (Unhelpful)
MrGrimm888's avatar

Wulf. I was painting a roof, in downtown Charleston, several years ago. I do used to do it, for side money.
I saw a silver cylindrical object, with no wings, and no exhaust smoke, or contrails. It made no noise. It seemed to be moving, fairly slow…

I’m not saying that it was a UFO. But. I’ve never seen anything like it.
When I got home, I researched it online. To my surprise, there were many reports, and videos of such a craft…
Some videos, showed them, just hovering…

It doesn’t really fit, the description, in the “details.”

I guess I just rank it, as unexplained….

There’s definitely some odd stuff, up there…

LuckyGuy's avatar

Most people are not aware how many weather balloons are released each year. Twice per day from each of 900 stations around the world and about 100 in the US. The balloons can travel over 100 miles and reach altitudes of over 100,000 ft where they burst and drop their parachute equipped instrument package. They can pass through wind currents of over 100 mph and then suddenly stop when passing through still air.
Here is an informative kid’s guide to weather balloons.

Over 10 years ago I was a technical advisor on a project that used a special weather balloon to lift a multistage rocket designed to put a small cubesat (10cmx10cmx10cm) in low earth orbit.
Anyone on the ground would have been baffled by the motion and contrail had they noticed.

MrGrimm888's avatar

^I researched all known weather balloon, and drone designs. Well. Unclassified ones. It took me 4 days. I didn’t find anything like what I saw. I am a skeptic. And remain so. It is just something I cannot explain.

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