Sunday, April 28, 2013


Chiles Redux 

Reconstruction of the actual view of the object as seen from the DC-3 cabin
What is referred to as the Chiles-Whitted UFO encounter involved a night sighting from a DC-3 of a cigar-shaped object in 1948. This case has been considered one of the 'classic unknowns' of UFO history. However a detailed analysis of this sighting, taken together with other sightings the same evening, clearly show it was an earth-grazing fireball. It was not a nearby object traveling at 700 mph half a mile away and 500 feet above the Chiles' aircraft, but a disintegrating meteor, passing 80 miles away at 90,000 feet at a speed of 18 miles/second. If we go back to the Air Force Office of Special Investigations (AFOSI) original reports (available at the Project Blue Book Archive) and plot the bearings and altitudes of the objects sighted on that night, no other conclusion can be reached.

In 1948, earth-grazing fireballs were not recognized by science. The AFOSI investigators did not get the information in the terms later standard for scientific analysis. They asked the witnesses to estimate the distance, size, and speed of a luminous object sighted at night. This required the implicit assumption that it was the size of man-made objects and flying at speeds and altitudes contemporary aircraft might achieve. Later standard Blue Book forms would ask the observers to estimate the apparent size (compared to the moon), the elevation above the horizon, and the direction and duration of a sighting. This kind of information could then be analyzed to determine if it matched a small, slow, close object or a much faster, larger object farther away.

Based on the assumptions that the mundane speeds and distances reported were correct and the 'fact' repeated over and over that 'it couldn't be a meteor because meteors do not fly horizontally' AFOSI convinced themselves it was an extraterrestrial object.

The sightings of that evening were:

  • Eastern Air Lines pilot Feldvary, Trip 573, reported sighting an object from his DC-3, flying from Washington DC to Raleigh, North Carolina. It was some time after he had checked in with Blackstone control at 0219. He estimated the time at about 0230. The object was traveling about 20 deg over the western horizon, at a heading of around 230 deg (e.g. slightly west from his heading of 215 deg), and travelled through an arc of 80 degrees. Although no duration was given, it seemed to have 'terrific speed'.
  • Eastern Air Lines pilot Mansfield, Trip 571/23, reported sighting an object from his DC-3, flying from waypoint Blackstone to Greensboro, North Carolina. It was also some time after he checked in with Blackstone. He also estimated the time as 0230 (it may be he discussed the sighting with Feldvary and assumed the same time). The object was traveling 'in a horizontal direction, slightly above the horizon, at a heading of around 210 deg (e.g. slightly east from his heading of 240 deg). He did not report the arc of travel, but said it was only in sight for 3 seconds. This was probably a good estimate of the duration of the sighting, since the object "…was brighter than any I have seen before…" and he couldn't have avoided seeing it immediately as it began to flare in the large right side cockpit window of a DC-3.

At the time of these two sightings, Feldvary was flying about 60 miles east of Mansfield. So clearly the object had to be a considerable distance west of both aircraft to be low on the western horizon for both of them. If we average the two bearings reported, the object would have a bearing of 220 degrees, which is consistent with a bearing west of Feldvary and east of Mansfield.

  • Eastern Air Lines crew Chiles and Whitted, Trip 576, were en route from Houston to Atlanta, 25 miles southwest of Montgomery, Alabama, on a bearing of 50 deg when the famous sighting occurred. A strange object was sighted 'coming toward us at a high rate of speed'. It was flying straight and level, and created no noise or turbulence. It passed to the right side of the DC-3, at what they estimated as a distance of half a mile, a speed of 700 mph, at an altitude of 500 feet above their 5000 foot level. The object seemed to be 100 feet long, cigar shaped with rows of brilliantly illuminated portholes, with a stream of red fire trailing behind. What this translates to in objective terms was an object approaching at a bearing of 230 deg, at an elevation of 12 deg above the horizon, with an apparent size at closest approach of 3.4 deg (about seven times larger than the full moon). The object was only in view for at least 5 and not more than 10 seconds. Of course the close view in which details were seen would have been only for an instant as the object flashed by. The actual view from the cockpit at closest approach, as shown above, was rather mundane compared to the typical artists concepts of the encounter.
  • Air Force contract employee Massey sighted a cigar shaped object with a trail of flame from the aircraft ramp at Robins AFB, near Macon Georgia. Unfortunately he was not asked the elevation of what he saw above the horizon. He saw it first 'overhead'. This apparently meant in the sky to the west of his position, since although he stated he was facing north, he didn't see it come 'out of the north' and people normally watch things in their field of vision, not straight above them. It then traveled in a southwest direction, until disappearing in the distance. He estimated the object to be traveling straight and level at 700 mph, an altitude of 3000 feet, and having the 'size of a B-29'. He estimated the duration as 20 seconds and the time of the sighting as 0140 or 0150 based on the departure time of an aircraft he was preparing (this one-hour difference from the other sightings is not commented on by AFOSI, although they considered this the same sighting as Chiles). Massey was asked if the thought it was a meteor and said no, because 'a shooting star falls perpendicular. This object was on a straight and level plane'. Massey claimed to have seen V-1's in flight and even a V-2 launch in World War II, the latter 'during the Battle of the Bulge'. This was perhaps possible. V-2 Gruppe Sued operated within 50 miles of the front lines near the south Ardennes in November-December 1944 before being moved behind the Rhine.

Putting together in terms of the positions and bearings of the aircraft and the objects sighted, and the locations of the observers, the following consistent result is obtained:

Plotting of the four sightings show a consistent course for the object
Which is clearly the track of what science now knows as an Earth-grazing fireball. Such rare events were only accepted by science in 1972 when one was actually photographed and filmed as it flew over Utah.

AFOSI's assessment was that the first two sightings were of a different event - because the object was 'meteor-like', travelled at 'terrific speed', and flew 'parallel to the horizon', which was seen as different from the other two (which were reported as flying at 700 mph by 'trained observers'). They did not seem to notice that the bearing of the object sighted in the first two sightings was the same as that observed by Chiles and Massey, or that estimates of the size and distance of an object at night would be based on it being a conventional object, not something unknown to science or popular culture at the time.

The sighting was sensationalized by the press in books, including that ghost-written for one-time Project Blue Book commander Ruppelt. The sighting was later embellished, with the object coming 'within 700 feet', the aircraft being 'buffeted by turbulence', Chiles having to 'swerve to avoid collision'. None of which was in the original report…

In fact the original sighting report is rather mundane. The object was only in sight for perhaps only 5 seconds, was seen to be about seven times the size of a full moon (but only for a second at closest approach), appeared to be coming head on but then passed the aircraft to the right, at a closes approach estimated at half a mile, and caused no noise or turbulence. Based on this brief glimpse, Chiles and Whitted produced these sketches (considerably more informative than the later 'cleaned up' versions):



Today, after many movies about asteroid impacts, and especially the very real Chelyabinsk event, no other conclusion would have been reached by the observers or investigators but that this was a meteor. The cigar-shaped (dark, unseen) form was defined by the brilliant 'windows' on the object, which were undoubtedly the object disintegrating into glowing fragments as it passed through the atmosphere.

Complete article at UFO DNA

15 comments:

  1. See 'UFO Iconoclasts' for my comment.

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  2. Nice blog! Thanks!

    Lance Moody

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  3. Part 1

    Luke, your analysis as presented here is based entirely (so far as I can tell) on geometry and glosses over some of the other issues attached to the case. As an aerospace engineer, a number of questions come to my mind. I wonder if you’ve thought about them?

    The first question is timing. You have linked 4 different observations together and implicitly assume they were all part of the same event. Let’s start with the pilots’ observations. The two Eastern Airlines crew that were southbound from the DC area both reported sighting the luminous object at about 0230 hours. According to Edward Condon (“Scientific Study of Unidentified Flying Objects”, 1968) the original Chiles and Whitted report to the USAF placed their sighting at 0245, or 15 minutes later. As a pilot, I tend to give relatively high credence to pilot reports, and I know that the air traffic control system places a lot of importance on maintaining schedule discipline. I would find no a priori reason to believe the two southbound aircrews about the time but not believe Chiles and Whitted. Do you have some information that I don’t have that would resolve that confict?

    The fourth observation that you link in was, of course, the ground observer Massey at Robins AFB. He said the object flew overhead at 700 mph and 3,000 ft at some time between 0140 and 0150, local and was in sight for about 20 sec. In other words he saw the object perhaps 40 to 50 minutes before the southbound Eastern Airlines crews. You mention that the AFOSI considered this sighting to be part of the greater “Chiles-Whitted” sighting event, but how do you or how did they, reconcile the timing mismatch? Was Massey right about the sighting angles but wrong about the time? Again, do you have some information that I don’t that would resolve that confict?

    Based on the agreement between the southbound Eastern Airlines flights and the Chiles-Whitted flight, you infer that the object (if, indeed it was one object) was moving on a bearing of about 220 degrees. I agree with that assessment, IF there was only a single object moving along a relatively continuous flight path. Once you assume that whatever Massey observed was one and the same as what the Eastern Airlines flight crews saw, then you have a point ion the map and the slope of a line going through it, so you obviously have an approximate ground track for the object. I couldn’t make out all the lettering on the graphic that you included in your analysis, but it looks like the ground track you generated was in the range of about 800 miles, from the time the southbound Eastern Airlines flights saw the object abeam their positions until the ground track crossed the Gulf Coast.

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  4. Part 2


    You present a conclusion at the front of your analysis that, “It was not a nearby object traveling at 700 mph half a mile away and 500 feet above the Chiles' aircraft, but a disintegrating meteor, passing 80 miles away at 90,000 feet at a speed of 18 miles/second.” I’m not sure how you derived the 18 miles/second figure; perhaps you started with that result as your desired outcome and calculated backwards to get that figure? Assuming for the sake of argument that it is correct, then the object would have traversed the 800 mile track in about 45 seconds. That would have allowed BOTH the southbound Eastern Airlines crews and Chiles and Whitted to have seen the object within the same 1-minute interval.

    Be that as it may, there is then the question as to what altitude (above ground level, or AGL) the object was moving at. You make the claim that:

    “At the time of these two sightings, Feldvary was flying about 60 miles east of Mansfield. So clearly the object had to be a considerable distance west of both aircraft to be low on the western horizon for both of them.”

    That’s not necessarily true. No question the object was to the west of them, but how far? If both Eastern flights were at approximately the same altitude with wings level and the object itself were approximately in the same horizontal plane, then the object would appear to be approximately on the horizon, regardless of its absolute horizontal separation distance.

    But let’s take your estimated ground track as representing the actual one. Again, by my eyeball estimate it looks like the object was approximately 200 miles abeam pilot Feldvary and on his horizon, when he reported the object. Due to the curvature of the earth, if the object was on his horizon, it was about 70,000 feet above his altitude. To that figure, we should add whatever Feldvary’s altitude was—perhaps 20,000 feet? Coincidentally, that total (90,000 feet) happens to be exactly the same altitude that you give as the estimate for the object’s altitude as it passed Chiles and Whitted, some hundreds of miles away.

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  5. Part 3

    So the implication is that the object was at 90,000 feet (≈ 27 km) when first seen by Feldvary and Mansfield and also at 90,000 feet when it passed Chiles and Whitted, suggesting, I suppose that it was flying at a constant altitude above the ground over that ground track.

    Meteors, of course, don’t do that, even earth-grazing ones. At 18 miles/second, the path that a meteor would take in passing by the earth would be, for all practical purposes, a straight line (in astrodynamics, we call that that straight line the “approach asymptote”). If you can, picture in your mind, the approach asymptote of a bolide passing by the earth at lower and lower altitudes. For reference, the orbital altitude of the International Space Station is about 250 miles (400 km, plus or minus). A space rock on an approach asymptote at Space Station altitude would whiz by the earth without even creating a visible glow and would therefore not technically qualify as being a meteor. At somewhere around 125 km altitude, the approach asymptote would just “kiss” a density level of the atmosphere where the air would start to be thick enough to cause incandescence and thus be visible (briefly) as a meteor. At this threshold altitude, there is enough atmospheric density to cause visible incandescence, but not enough to slow the original bolide very much, so it would continue on out of the atmosphere on a straight line. (People mistakenly refer to that as “skipping off the atmosphere”, but it’s not really doing that.) As the approach asymptote gets lower and lower, the density of the atmosphere rises exponentially with depth. By the time you get to 75 km altitude, virtually all bolides are incandescent.

    Actually, it is the shock wave of compressed air standing out in front of the nose of the bolide that causes most of the incandescence. It is this exact same pressure on the nose that causes the bolide to decelerate. As the bolide decelerates, its path starts to deviate from a straight line and bends toward the earth. If the deceleration is severe enough, two things will happen; the deceleration puts inertial stresses (tending to cause breakup) in the body of the bolide and the path of the bolide bends down until it is pointing at the ground. At that point, it is no longer an earth-grazing bolide, it is an earth-intercepting bolide. Once breakup begins, it proceeds exponentially, terminating in a bright flash. You can see that the difference in altitude between when a bolide goes from earth-grazing to earth-intercepting is pretty small; most meteors breakup in the 50 to 100 km range. So, if the approach asymptote is lower than about 50 km, the meteor has a good chance of not leaving the earth. The daylight earth-grazing 1972 event over the US and Canada had an altitude of lowest approach of about 57 km and lost about 5% of its velocity. If the approach asymptote intercepts the atmosphere at an altitude from 50 up to about 120 km (a band of about 50 km), it has a chance of being an earth-grazing bolide. If it is above that, it will not be a meteor at all. If you take the ratio of the cross section of the earth to the cross section of the 50 km thick band of atmosphere, you get the relative probability of a meteor being earth-grazing or not. My back of the envelope calculation says the probability of a visible meteor being an earth-grazer is about 1/2 of 1%. That explains why they are not seen very often. In my lifetime of 60+ years, I have seen only 1 that I am certain of.

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  6. Part 4


    By the way, I question whether it is true that “In 1948, earth-grazing fireballs were not recognized by science”. It may well be true that nobody had a good movie recording of such an event until the 1972 event, and for that reason the general public and the PR types that the USAF had working in Blue Book might have been clueless. But I can’t believe that any professional meteoriticist (such as Lincoln La Paz) would have have doubted the theory behind earth-grazing fireballs.

    What this discussion is getting at, however, is that if the object that was the subject of the Chiles-Whitted UFO case was really at 27 km altitude when it was seen by Feldvary and Mansfield going southwesterly AND it was also at 27 km altitude when seen by Chiles and Whitted hundreds of miles to the south, it would have to have tunneled through the earth somewhere in between if it was moving in a straight line, as earth-grazing fireballs do. Clearly, it was not an earth-grazing fireball.

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  7. Larry, thanks for your criticism. Most of the points you raise I went through in reaching my conclusions, but I didn't want the post to ramble on. So:

    1 - Click on the map image to see a larger version with legible notations. This would clear up some things.
    2 - I calculated the distance using geometry over a spherical earth; I didn't assume a conclusion and then 'back into it' as you suggest, except to note that any reasonable estimate of the distance from Mansfield and Fedlvary put the object on a course that matched the observations of Massey and Chiles. Indeed, when I started the analysis I was thought the outcome would be an estimate of the actual velocity of the object. Looking at the map, note that Feldvary was 60 miles east of Mansfield, and the object was 20 degrees above the horizon as seen by Feldvary. Even if the object Feldvary saw was directly over Mansfield, it would have been at an altitude of 20 miles. But it wasn't; Manfield also saw the object near the horizon, although no elevation was given, but presumable well under 45 degrees, otherwise it wouldn't have been judged as 'near the horizon'. It had to be a substantial distance and elevation from them both. And any such distance and bearing (you can adjust the trace of the course back and forth over land if you want) would put the object between Massey and Chiles, just as described by them.
    2 - I calculate the object as at 40 miles altitude and 50 mi/sec when seen by Feldvary and Mansfield; and at 16 miles altitude and 15-18 mi/s when seen by Massey and Chiles. So indeed it was very rapidly decelerating and descending. Perhaps enough to finally bring it to splash down in the Gulf of Mexico...
    3 - I state that earth grazing fireballs were relatively unknown at the time because of the constant statements in the AFOSI reports that 'it can't be a meteor because they don't move horizontally', which is the common belief. Indeed, the scientists attached to the project did decide it was a bolide, but this was not accepted by the USAF.
    4 - The time given by Chiles was probably accurate, because of the impact of the sighting and the conversations with traffic controllers about the object. The reports by Mansfield and Feldvary were made a couple of weeks later, only after a USAF request to airlines to report if anyone else saw an object that night. They both gave a time fifteen minutes earlier, but this was just because they both knew it was sometime after they had checked in with the Blackstone controller, which presumably they would know the usual times of that event based on their departure times. Neither remarked to air traffic control at the time and had no reason to take note of the time on their chronometer. I mention the possibility that they had discussed the sighting with each other and maybe had a concensus on the time. As far as Massey's sighting being an hour off, note that at this time daylight savings time was different from state to state (indeed if you look at the Eastern Airlines flight schedules of the time you'll see they had to indicate both a consistent 'aircraft time' on the schedule and the local time, which varied even within a time zone). Therefore there could be some confusion. The AFOSI investigators considered it a sighting of the same object, so whatever local understanding of the relative times they had at the time allowed them to reach that conclusion. The alternative is to believe that an extraordinary object was seen by Massey, went somewhere for an hour, then flew again exactly one hour later on the same bearing and position past Chiles. Even the Chelyabinsk analysis was thwarted by differing time hacks on the modern electronically-coordinated video footage (including the satellite imagery (!) ). So it is easier to believe that four sightings of an extraodinary object at around the same time on one eventing are the same object, rather than taking every time given in 1948 was precisely accurate and trying to make deductions from that...

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  8. Part 5

    Also FYI, I checked the historical records for the Montgomery AL airport on the day in question at:

    http://www.wunderground.com/history/airport/KMXF/1948/7/24/DailyHistory.html

    As you can see, they report visibility as 10 miles, with significant events being rain and thunderstorms. However, it doesn't say at what time those events occurred. Anyway, visibility would be a question when someone is supposed to have seen an object 80 miles or more away.

    Maybe someone has more precise weather information than I could find?

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    Replies
    1. To obtain the surface data from the NCDC archives go to: www.ncdc.noaa.gov
      Select: Data Access (at top)
      Select: Quick Links
      Select: Integrated Surface Data, Hourly, Global
      Select: ISD/CDO (under Integrated Surface Database, Hourly, Global)
      Click: "SIMPLIFIED Options"
      Click: "Agree to terms"
      Input: Geo region: North America
      Click: "Continue"
      Click: "Continue"
      Select: Station ID in the list, and "Continue"
      Select; Date Range and "Continue"
      Check: Inventory Review, enter email address, and submit
      Click: on the URL to view records (wait a bit for the records to load)
      A copy will also be sent to your email.

      Delete
  9. http://www.bluebookarchive.org/page.aspx?PageCode=MAXW-PBB4-45

    "...The night was clear with a bright moon and broken cloud coverage of 4/10 at 6,000 feet..."

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  10. OK, thanks for the clarification. I mistakenly thought you were claiming something that you are not. Now I think I understand what your assumptions are. Basically, you are assuming that the line along which the object travelled (the approach asymptote) was at its point of lowest approach to the earth (perigee) right when it flew by Chiles and Whitted. That would mean that to them, it would appear to be approaching in a horizontal plane. In order to create the same viewing angle that they reported at that instant (half a mile away and 500 feet above) you assumed that the object was about 16 miles (about 85,000 ft) high because it would have been about 80 miles away. You then traced the trajectory back to the point where the object was when it was first seen by Feldvary. I’m going to refer to that as point “A”. By simple geometry, the object would have been at about 40 miles (211,000 ft) altitude at point A, taking into account the curvature of the earth. The ground track distance between points A and C comes out right at 600 miles, by my calculation. At the point midway between A and C (call it point “B”) you put the object at 17 miles altitude (90,000 ft). That would put it about 300 miles away, on Chiles-Whitted’s horizon, if they were able to see that far. I reverse engineered your geometry, and agree that there is a straight line connecting points A, B, and C.

    So now, we can think about what the physical consequences of such a trajectory would be. In my day job, I design space missions that require atmospheric entry, so I am familiar with the physics involved. Let’s assume that the speed at point A (it’s “entry velocity”) was 50 mile/sec when it was at 40 mile altitude, as you postulate and that it’s speed at point B was 32 mile/sec when it was at 17 mile altitude. That means it lost 18 mile/sec of speed somewhere on the A-B path when it was descending by 23 miles over a path length of 300 miles. It turns out that such an object would not be decelerating uniformly over that course.

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  11. The force that causes a bolide to decelerate is essentially the ram air pressure on the front face of the bolide. That pressure is numerically equal (in appropriate units) to the density of the air (ρ) times the speed (v), squared, all divided by 2. Aerodynamicists refer to that quantity as “q”, so q = (ρ v2)/2. The density of the atmosphere increases exponentially with depth into the atmosphere from the point of entry, and that is where the surprise lies. The air density at 17 mile altitude is about 165 times thicker than it is at 40 mile altitude. That means that the object would have maintained most of its entry velocity until it got down close to the 17 mile altitude.

    The average speed between point A and B was (50 mile/sec + 32 mile/sec)/2 = 41 mile/sec. At this average speed, the object would have taken about 7.3 seconds to traverse the 300 miles between A and B. In reality, however, the object would have traversed the first 240 miles (my estimate) at the original speed in about 4.8 seconds. It would then have traversed the remaining 60 miles or so at an average speed of 41 mile/sec giving it approximately 1.5 sec to slow from 50 mile/sec to 32 mile/sec. By my (further) back-of-the-envelope calculations, the object would have had been experiencing an average of 2000 g’s of deceleration and an average stagnation-point pressure of about 12,500 psi. The peak values for those quantities would probably have been larger than the average values by perhaps a factor of 2 (my estimate). I think this would have been enough to cause the vast majority of naturally occurring bolides to break up.

    If the object were travelling at the lower speed of 18 mile/sec at point C (only about 55% of the speed at point B), then it would have experienced quite a bit lower dynamic pressure and decelerations at that point, even though the atmosphere would have been denser at the 16 mile altitude. The reduction in velocity more than makes up for the increase in air density.

    The point here is that if the object were going to break up in the atmosphere along the path A-B-C, it probably would have done so at point B, at least 300 miles ahead of Chiles and Whitted. The forces on the bolide would have been getting steadily weaker from that point on.

    When meteor breakups occur, they usually proceed exponentially fast. When the internal stress in the body of the bolide caused by deceleration exceeds the bearing strength of whatever the bolide is made of, it starts breaking apart. Because each piece of the original body is now smaller than the original, all the pieces immediately experience even higher internal stress (because of the square-cube law of scaling) and break apart, forming even smaller pieces, and so on. It is not really an "explosion", but an exponentially increasing disintegration. Each piece, of course, is still travellng at the cosmic velocity it had when breakup started and produces its own incandescent shock front. But now, the total surface area of all the pieces and therefore the total optical power being radiated into the atmosphere is many orders of magnitude greater than when the bolide was a single piece. It’s when this kind of breakup occurs that you get a massive flash and the deposition of the bolide’s entire momentum into the atmosphere that creates the pressure wave that blew walls down and windows out in Chelyabinsk, earlier this year.

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  12. If that had happened, I think there is no question it would have been observed by Feldvary and Mansfield not to mention observers on the ground. Clearly, the object did not break up at point B. But I think you are right that the object that those two saw at 0230 was most likely a common meteor. That means that either it was an uncommonly strong one (nickel-iron type) or it was perhaps somewhat higher than your estimated altitude at point B and not heading for perigee at point C. In that case, it would have continued on right past point C at a higher altitude and perhaps sailed right back out of the atmosphere.

    This leads me to the conjecture that there were two separate events. Feldvary and Mansfield sighted a conventional meteor entering the atmosphere at a fairly flat angle at 0230 which did not break up, and Chiles and Whitted did not see it pass their position 10 seconds later, for whatever reason. At around 0240, Massey saw an Unconventional Flying Object sail past his position (under a cloud deck, or at least under the altitude at which the air temperature fell below the dewpoint and caused poor visibility). Perhaps he was confused about which time zone he was in and so, erroneously reported the time as forty minutes past the hour of 0100 unstead of 0200 (i.e., 0140). Five minutes later, Chiles and Whitted saw the same unconventional object fly past their position at about the same altitude as Massey reported. The fact that Feldvary and Mansfield sighted a conventional meteor 10 to 15 minutes earlier than Massey and Chiles and Whitted sighted an unconventional object is not surprising, as millions of meteors occur every day

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  13. Luke: thanks for the pointer to the Blue Book archive; that answers a question I had. Chiles and Whitted were flying a DC-3. Most piston engine/propeller airplanes operate most efficiently at a cruise altitude around 8,000 ft, yet they were cruising at 5,000 ft, and I was wondering why. Now it is clear that they were cruising at the highest altitude they could consistent with their magnetic course being between 0 and 179 degrees and being below the clouds. I would interpret the aviation weather reported in the Blue Book report as meaning that the air was "clear" of other well formed clouds below the bottom of the cloud deck at 6,000 ft which covered 40% of the sky. In other words, the cloud deck they were flying under constituted the lowest clouds (probably also including ground fog). This is consistent with the National Weather Service records for the area (for example, Montgomery but also others) which show that there was about a 5 to 6 degree F temperature difference between the air temperature at the ground and the dew point. Given the nominal lapse rate of about 2 degrees F for every 1000 ft of altitude, one would predict that the air would start start getting saturated a few thousand feet above ground level. Atmospheric haze starts occurring when the relative humidity reaches 100%, but solid cloud formation usually requires the air to be at the supersaturated condition of perhaps 105% relative humidity. I suspect that haze (microscopic water droplets) underneath the cloud base is what contributed to the visibility being reported from the ground as in the 10 to 15 mile range.

    In any case, I was not aware that Chiles and Whitted reported the object as pulling up into the clouds as it passed them. It may be plausible that they could have mistaken the fiery tail of a meteor as the cigar-like shape of a UFO, but they clearly reported the object as maneuvering relative to the bottoms of the clouds (6,000 ft). If the meteor in your theory never got closer that 16 miles to the ground, I don't see any possible way it could have been mistaken for what Chiles and Whitted reported.

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