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Explaining the O'Hare Airport UFO (day events)

  1. Nov 22, 2008 #1
    The physics behind the scene on some type of UFO reports (events on clear day) is explained here.

    This is an important issue to aviation security, and if you agree with this explanation make some effort in spreading the word.
    Jet planes have HOT invisible exhaust gases.
    In other cases just find the heat source (ex. a long queue of cars).
    Geometric configuration on the environment makes those hot gases trapped
    in some sort of bubble with a more or less defined surface.

    A jet plane was near the event scene warming engines as a preparation to taxi away, and finally it goes away.

    The no wind condition prevents the quick spreading of gases.
    Turbulence became reduced and a bubble is formed with a more or less defined surface.

    The delimiting surface between the hot region and the colder environment is reflective to tangential rays and gives the grey colour that makes people think they are seeing a metallic object, with stealth properties. It can only be seen from some directions and became opaque preventing the vision of background buildings and other known pre-existent features.

    Hot air goes up and it reveals the 'UFO' hovering the airport.
    Mutatis mutandis for other scenarios.

    Finally the hole in the clouds became explained. Yes, you have guessed. Hot gases have evaporated the little drops of water in the clouds by releasing the heat.

    In the sketches the bubble is dark colour for obvious reasons. In fact the bubble is transparent.

    Some accidents happened because the no window condition prevents bubbles from spreading and inside them there is a lack of oxygen. See link bellow.
    I do prefer a UAP designation (Unidentified Aerial Phenomenon)
    just because they are not flying neither are objects.
    ( observers and investigators never report on wind strength, and a lot more things became unreported )
    some links :
  2. jcsd
  3. Nov 22, 2008 #2
    Re: explaining O'HARA airport UFO (day events)

    Hmmm, I'm having trouble with that.

    Would airline pilots possibly have seen exhaust gasses before?

    If so, would several of them have reported this incident as something out of the ordinary?
  4. Nov 22, 2008 #3
    Re: explaining O'HARA airport UFO (day events)

    in this site you will see a report of 1998 close encounters. near misses
    (UFO baffles aviation experts)
    the graph shows 159 incidents ; 18 with actual risk; 30 compromised aircraft security

    if you go to an airport you will notice that exhaust gases are transparent/invisible, as I said above.

    This is the why that reports doesnt mention what they do not see.

    In calm weather they turn into a security problem.

    the physics is about light refraction/reflection on volumes/surfaces of different refraction indexes. The reflected light comes from ambient, problably the sky.

    the accident here reported http://aviation-safety.net/database/record.php?id=20080117-0
    is a little bit different, if, and I repeat if there is no wind then the previous aircraft that landed leaved a trail with low oxigen content, and engines faied.
    Last edited: Nov 22, 2008
  5. Nov 22, 2008 #4

    Ivan Seeking

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    Re: explaining O'HARA airport UFO (day events)

    Nice post heldervelez. Thanks.

    Do you know for a fact that a plane was warming its engines in the required location?
  6. Nov 22, 2008 #5
    Re: explaining O'HARA airport UFO (day events)

    What is my desire is limit the discussion, to O’Hare airport like events, because it represents a whole class of UAP phenomenon, as they are quite common.
    I've done my homework, spotting the underlying physics, not with this event in particular but reading a lot of reports from other UFO events, searching in databases, looking for patterns.

    So I'm pretty sure that in some of the descriptions of O’Hare airport event we will find a reference.

    -------------------- Next
    If I find some acceptance on the physical mechanism that I focus for this class of events, (especially because it relates with aviation security)
    then I will move for problems with photograph reports (that’s a marginal problem) and, finally the more general explanation of the more spectacular sightings of nightly UAP (UFO).

    ----------------------------- Proposal
    I don’t like very much to write. If you think that I can count with participative posts I can point the way, ‘saying were to look’ with a few sentences, always saying what I found and reasoned and helping the community.
    I hope that the community is physically minded and can accept the proposal.
    Finally I’ would like that one of us, with more writing and sketching capabilities than I have, make a final post with the conclusions and make the credits to myself and also to the community.
    I think it has more fun and it will be far more interesting the participation of more people.
    This first post was to show that I’ve done the homework.
    I know that a physical solution is not good for a lot of ufologists, after all is a way of life. There are investigators with a career, congresses, books to write and they will oppose.
    But don’t we deserve the truth, physically based?
    With this first post I’ have uploaded 3 simple sketches (jpg) to illustrate the geometry of the problem. I know that they are very simple, but I have no time to spend in the beautifying.
    They became marked to approval. I think that the post will be better with them.
  7. Nov 22, 2008 #6

    Ivan Seeking

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    Re: explaining O'HARA airport UFO (day events)

    I understand.

    This is a bit bothersome. We can't make assumptions.

    It is entirely appropriate to pursue an earthly, scientific explanation for UFO reports. However, we have to be careful to keep this in perspective. We can't just assume that this is the correct explanation for any or all UFO reports. Each case has to be considered on its own merit. And the explanation you offer needs to be considered in detail. But your motives are entirely consistent with those of this forum.

    I don't see your attachments?
  8. Nov 22, 2008 #7
    Re: explaining O'HARA airport UFO (day events)

    uploading the 3 drawings

    Attached Files:

  9. Nov 22, 2008 #8
    Re: explaining O'HARA airport UFO (day events)

    The object was seen to suddenly accelerate straight up through the solid overcast skies, which the FAA reported had 1,900-foot cloud ceilings at the time.

    because the diferential of temperature in the ground is lower it starts moving up slowly, but as it gains altitude the differential becomes higher and the movement starts accelerating.

    The pilots of the United plane being directed back from Gate C17 also were notified by United personnel of the sighting, and one of the pilots reportedly opened a windscreen in the cockpit to get a better view of the object estimated to be hovering 1,500 feet above the ground.

    That night was a perfect atmospheric condition in terms of low [cloud] ceiling
    end of quote

    they never talk about the wind.

    I affirm that there is no wind, are you in position to make a confirmation? I think its more pertinent than finding the particular jet responsable for the occurrence. Most probable there were several of them given the size of the 'object' (700 foot tall)

    Dont forget that I'm talking about a class of events. This one in O'Hare is an example.
    If I were there I'll have notice the weather conditions. No one seemed to care about.

    in the map
    I cant even find C17 gate.

    The first time I searched (not recently) I've found a more complete report than I'm finding now.
    I'will try to find but I remember again that I've no time, and others can pursue the local conditions.

    After all I've made my quest for the explanation on UFO's several years ago. When I rested, I was satisfied with myself.
    After all I can remain in silence, as usual, because the fun was in the pursue of truth itself.
  10. Nov 22, 2008 #9
    Re: explaining O'HARA airport UFO (day events)

    I'm only willing to explain events of the type "sightings by night" with no physical contact but electromagnatic effects will be also addressed, no abductions or other phsycological effects.
    it represents a broad range of reported events.
    I think it is fair if I ask for colaboration because inducing people in the reasoning, finding in the wikipedia, finding for images is some homework that people must do if they want to know the truth.
    I'm 54, electronic engineer and I'will only refer simple physics. My wife and daughter need time, as my other projects and work.
    Last edited: Nov 23, 2008
  11. Nov 23, 2008 #10
    Re: explaining O'HARA airport UFO (day events)

    the complete report can be downloaded from here
    Case 18 Main Text 1 Rev. 07/24/07 R.F.Haines et al.
    It was a www.NARCAP.org full report (152 pages).
    National Aviation Reporting Center on Anomalous Phenomena1
    Probably also available at narcap.
  12. Nov 23, 2008 #11
    Re: explaining O'HARA airport UFO (day events)

    Ok, now I have some serious problems with the physics.

    You claim this 'ball' of hot gas is contained by some sort of 'geometrical' phenomena, please elaborate. Any gas in the atmosphere will mix with any other gas to obtain a uniform concentration. That's why farts don't stick around forever (thankfully). This is called diffusion, and the rate at which they mix is proportional to the temperature, exponentially so infact.

    Wind is not needed for a ball of hot gas to disperse, it does that by itself with the random thermal motions of the atoms/molecules. A temperature gradient in the atmosphere will cause a change in refractive index yes, but referring to my previous post, several United Airlines pilots reported seeing an 'object' out of the ordinary at O'Hare. These guys are seeing jet exhaust every day, and I'm assuming this wasn't the first calm day in the airports' history.

    Of course hot gasses will cause optical effects, but you're proposal is lacking in physics and fails to explain why this hot gas was somehow magically contained in three dimensions with a well defined boundary.
  13. Nov 23, 2008 #12

    Ivan Seeking

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    Re: explaining O'HARA airport UFO (day events)

    Based on the upward velocity of the hot air stream, the rate of effusion of the hot air, and the altitude of the clouds, it seems that one could estimate the size of the hole in the clouds that we would expect, if any. Perhaps there is an existing model that could be used.

    The off-topic posts were moved to this thread.
    Last edited: Nov 23, 2008
  14. Nov 23, 2008 #13

    Ivan Seeking

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    Environmental or Industrial Engineering: Smokestacks

    What happens after the exhaust stream leaves the stack is an area of interest. For one, this is considered in order to calculate the required height of the stack.
    Last edited: Nov 23, 2008
  15. Nov 24, 2008 #14
    Mr Ivan,thanks for your contribution.

    The model of this event must begin with a simple model, instead of a complete model of the airport environment, because we don’t have access to the traffic conditions and used lanes on that particular day.
    So, although I’m not interested in the modelling itself (***), because of the time to be invested, I can contribute with some ideas. At least it is a good exercise.
    We have to use a CFD code (OPENFoam as good features, is opensource and free, or another CFD code) to do the thermodynamic calculus.
    Model the atmosphere initial conditions with a gradient from hotter at the ground level and decreasing temperature with crescent altitude.
    Model the exhaust gases: Output temperature, total mass/second and velocity. The engine is essentially a burner and a blower.
    It is reasonable to assume a lower constant level of emission instead of a pulsed emission (one pulse of duration X for each plane take-off), as a result of time integration with a slow dispersive medium.
    At the take-off the engines were pointed down to ground, and due to the high velocity of the output we can assume a simpler model with a constant influx of heat concentrated at a small surface area at ground level. We can also assume no obstacles which points to a cylindrical configuration.
    Until know thermodynamics expertise was needed and the CFD will output the temperature/pressure profile at a later moment, not necessary at an equilibrium point.
    Then we must know more about the physical characterization of the gases, in particular the index of refraction (IOR). I think that the IOR is dependent on temperature/pressure. I think we can get such data from internet, but not sure.
    Now we need to translate the map of temperature/pressures distributed in space to an IOR map with a spatial distribution.
    Then we need to visualize with the help of another package.
    PovRay, Maya, (I don’t know if ‘light++’ package will do the job, but it is an impressive package). Model the space as an ‘onion’ (*) assigning to each layer a specific IOR. Model the illumination: ambient diffuse light coming from all directions superimposed with a stronger plane of light coming from near horizon at low angle (due to the sun-set).
    Model the clouds also, as they contribute with another plane of light from above.
    Finally chose an appropriate point of view, by chance or intuition, from where you can see the light rays, tangent to the ‘surface’ (**), suffer a reflection and provide a metal grey visualization.

    (*) ‘onion’ is a way of speaking. A spatial grid needs to be constructed to represent the geometry of the temperature/pressure.
    (**) ‘surface’ is only a way of talking because it relates to a volume in the outer layers. The bending of rays is not at a definite surface and at a specific point as with a mirror, but along all the path of light. Inside the volume the rays get progressively bended.
    (***) I dont feel the need, personally, to do the modeling, because I have total confidence that a powerful source of heat and the absence of wind is responsible for this class of events.

    A comment about ‘objects’ we see:
    We see light, just, and only light, not objects.
    Our brain constructs a mental representation of a familiar object to associate to the seen light. We have a need to integrate the world around us into a framework that makes sense. This is a basic principle and only under this principle we are subject to optical illusions.

    A comment about the general shape of UFO's as they are usually represented in literature:
    It can be seen as the top part of the 'bubble' with a bump at the center due to the fact that heat is more intense at center. Think about it.

    Good work.
  16. Nov 24, 2008 #15

    Ivan Seeking

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    Without a formal analysis we can only guess for now, but I must say, I think you might be onto something here. It could account for the reported details of the event.

    I strongly urge that existing models be used where possible. A formal derivation from first principles could be quite a challenge, even for accomplished physicists. But if one could predict the size of the expected hole in the clouds, this could be used as a fairly definitive test.
    Last edited: Nov 24, 2008
  17. Nov 25, 2008 #16
    Here are some of the witness descriptions to compare it with:

    Are there any pics of the heat-light-reffraction that can show me what it looks like?
  18. Nov 26, 2008 #17
    I will illustrate with an example from common experience:
    You are driving a car in a very hot day, and your son (5 years old) is at your side.
    (for safety send him to the back seat after this experiment).
    He is looking to the road far ahead and exclaimed: Look, the road is wetted, is it raining there?
    No son, it is not water. You are just seeing the sky reflected in the hot air.
    Pa, it looks like water!
    As you are an adult you are not expecting to see the water in the road, so you know that it is not. You don’t believe.
    Your sun knows nothing about light bending and optical effects. He can only see water. He believes.
    The internal representation of what we see must conform to experience.
    In this experiment 'water' is an object.
    In the O'Hara event the 'object' is also the sky reflected in the hot air.
    But the ‘object water' colour is different from the one seen in this ‘object’!
    Yea, there is no black asphalt in the sky.
  19. Nov 28, 2008 #18

    Ivan Seeking

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    heldervelez, I have been in contact with someone who is not only a real expert on some of this, but who also likely knows all of the reported details of the O'Hare event. For the moment he wishes to only relay his thoughts for your consideration. I will add a few comments of my own as well. If anyone objects to this, I guess we could have Greg [the owner of PF] verify that the related personal email does exist as represented here.

    The first issue mentioned gets back to the rate of effusion. He seems to indicate that we might expect more a bubble, than a column of rising air. But his position on this was not entirely clear to me. Based just on my personal experience, particularly with campfires, I would tend to expect a column of air that effuses much less quickly than it rises. So, my own expectation would be that of a rising and expanding, approximately conical volume of heated air. But, again, without having done a formal analysis, I can only suggest that this is what we might expect.

    The next consideration was that we might expect this cloud-hole phenomenon to be fairly common around airports. That being the case, we might expect this to be well understood already. So I think the objection amounts to one of “where’s the evidence?” Why don’t we see this on a regular basis?

    To me it seems possible that we may be talking about something that occurs only under specific conditions. As a result, it may rare, and when it does happen, it may often go unnoticed.

    The next point may be a bit more difficult to counter. The alleged object was seen to hover at a fixed altitude for a couple of minutes.

    If the details of the event are known to this level of precision, then your explanation would seem to be in direct contradiction to the reported observations. My suggestion would be to determine the confidence that we might have in the reports of “hovering”. Perhaps this part of the story is not well supported, in which case we might allow for this. If on the other hand this directly contradicts the alleged facts, then it becomes more troublesome.

    The next two considerations are that of the angle through which the light is refracted, and the claim of a silvery disk. The objection made is that we would only expect refraction through an angle of less than one degree. So while we might select preferred positions of observations to coincide with your explanation, the facts of the case, as reported, do not agree with this. One witness was reportedly almost directly underneath the observed phenomenon. So in order for our explanation to work, we require more refraction that we would expect. Also, we have no reason to assume that the boundary layer between the hot and cool air would appear as a silvery or gray metal disk. While I do understand your expectations here and would tend to make the same assumption, we don’t know this to be true.

    Also, we don't really know how quickly a hole would form in the clouds above. Would this happen in a flash, or would it take place over a period of several minutes, or more? I don't think we can say without just guessing.

    The final point was that while you have the top of the bubble rising faster as it gains altitude, we might also expect it to slow as the temperature of the hot and cold gases approaches equilibrium. So, again, we need a rigorous model to make the correct determination here.

    Note: Fifty-five years ago (1953) the late Dr. Donald Menzel, Harvard professor of physics and (publicly at least) a UFO skeptic, proposed various atmospheric effects to explain UFO sightings, which included a formal theoretical model for a bubble of hot air. Your suggested explanation requires angles of refraction that far exceed even those of Dr. Menzel. And it is argued that he streched the applicability of his theory far beyond its range of potential application.

    You are invited to respond to these considerations, but in regards to the specifics of our rising air column, or bubble, what we really need is a reliable model to reference. We can’t do "science" by waiving our arms for much longer. It is important that we don't slip into pseudoscience.
    Last edited: Nov 28, 2008
  20. Nov 28, 2008 #19

    Ivan Seeking

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    Of course, if the cap of a rising cone of hot air is essentially bubble shaped, then an observer nearly underneath the bubble might view the light refracting through a small angle along the curved vertical wall of the cap - the boundary layer. So it seems possible to me that refraction through only small angles could still account for the reported observations. So it might be worth taking a look at this possiblity, but this still assumes that the appearance of the boudary would agree with the reports.
    Last edited: Nov 28, 2008
  21. Nov 29, 2008 #20

    Ivan Seeking

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    An email from Dr. Bruce Maccabee [our original guest contributor]. Dr. Maccabee is widely considered to be one of the top scientists actively engaged in UFO research. His specialty is optics, which is particularly useful to this discussion.

    Last edited: Nov 29, 2008
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