Fireflies: The X-15 ‘UFO’ Sighting Controversy.

Curtis Peebles
Magonia 78, June 2002

Between late November and mid-December 2001, the UFO UpDates Internet mailing-list saw an exchange of postings regarding the UFO sighting made by Maj. Robert White on his July 17, 1962 flight in an X-15. This provides a case study of belief, the interactions between believers and sceptics, how evidence is presented, and how it is accepted or rejected. Although there are similar exchanges every day on the various news groups, what makes this example different is the availability of data from the X-15 flight itself.

This includes the pre-flight plans, the transcripts of the in-flight radio messages and the post-flight debriefing, as well as flight data such as the Mach numbers, altitudes, and dynamic pressure on the vehicle. This, along with the historical context of the sighting, provides a benchmark against which the differing statements can be measured.

The thread began with a November 29, 2001 posting by James Oberg, which objected to a reference to the X-15 sighting in Filer’s Files 16 from April 1999. George Filer had said that the object was greyish in colour and 30 to 40 feet away, but did not mention that the object was tumbling and looked like a piece of paper. [1] Oberg commented that “engineers postulated he was seeing ice flaking off the engine nozzle, super-cooled by the liquid oxygen propellant and broken loose by the firings of the X-15′s attitude control thrusters once it was in space. This explanation came to satisfy everybody in the X-15 program, especially in hindsight when nearby tumbling ice flakes became a common sight on orbital missions.” [2]

Don Ledger made the initial reply to Oberg’s posting by saying, “Flakes of ice in the vacuum of space I can buy into but not within the atmosphere at supersonic speeds – and thirty to forty feet away tumbling in front of the pressure wave – which incidentally should be well aft of the X-15. That’s one strong piece of ice flake. NASA et al seem to be getting away with the ice flake explanation for a lot of sightings and to be honest-I think it’s getting a bit old.” [3] This issue, the dynamic pressure on the X-IS at the time of the sighting, became central to the subsequent debate the following day, November 30.

The issue was taken up by David Rudiak, who had been critical of Oberg’s earlier postings. Rudiak wrote that, “White reached an altitude of about 60 miles travelling about 4,000 mph. I don’t know at what point in his trip he sighted the object. Let’s assume it was at his maximum altitude of 60 miles. There’s not much atmosphere up there, but it’s also not a true vacuum. Meteorites made of rock and metal, not to mention satellites, start burning up at this altitude, but not this flat, fragile, completely non-aerodynamic ‘ice flake.’ “Yeah right!” he continued, “Furthermore, besides this flat ‘ice flake’ being impervious to vaporisation by frictional heat, it was also immune to frictional drag. After breaking off the engine in the rear, it somehow migrated forward to be seen tumbling outside of White’s side porthole.”

Rudiak then turned sarcastic, writing, “It’s truly amazing what ‘ice flakes’ are capable of doing in the imagination of a debunker. The physical properties of such ‘ice flakes’ are so remarkable, I’m surprised NASA doesn’t make our spacecraft out of them. Why use metals and ceramics when we could use ‘ice flake’ skins, thus eliminating frictional drag and re-entry problems, all with one simple, inexpensive material?” He concluded by saying, “I don’t know what it was either and am likewise open to reasonable suggestions. But `ice flakes’ strike me as physically impossible under the given circumstances.” [4]

Lan Fleming, a supporter of the face on Mars, took a different tack. Based on data from a French space website, he noted, “White’s X-15 flight in July of 1962 reached an altitude of 96 kilometres, which technically at least, qualifies as a space flight. There is probably still some atmospheric drag at that altitude, but probably not enough to prevent ice particles from ‘hovering’ near the plane for some time rather than being swept away quickly.” He then raised a different issue, noting, “I do wonder, however, where the water vapour that could form such ice particles came from. If there’s little air at an altitude of 96 km, then there also isn’t much water vapour in that rarefied air that could condense into ice particles. X-15 flights were very brief, so I would think waste water was not being dumped overboard, eliminating another possible source of ice. The ice would probably have to have formed while the plane was at lower altitudes. But this plane was moving at hypersonic speeds which generate enough friction at lower altitudes to require the plane’s skin to be constructed from heat resistant alloys. How does atmospheric water condense into ice on such a hot surface?” [51]

There was a series of postings on December 1. Rudiak sent a long and critical response, which centred on the issue of dynamic pressure. After noting that White’s flight reached 60 miles altitude, he continued: 
Is 60 miles up considered ‘space’? No, and furthermore Oberg knows it. If it were ‘space.’ then NASA would be conducting its orbital space missions there – save a helluva lot of energy, for one thing, boosting objects into orbit.

Why doesn’t the space shuttle or the international space station fly only 60 miles up’? Too much residual air friction, that’s why. In fact, the unshielded space station would start burning up and dragged out of orbit in no time, just like meteors start burning up at 60 to 70 miles altitude

At sea level, standard pressure is 760 mm of mercury. For every 10 miles increase in altitude, air pressure falls by a little over one order of magnitude. At 60 miles, the pressure has dropped nearly 10 million times

While that might count as a near vacuum in a lab on Earth, that’s not the way an object travelling thousands of miles per hour experiences it. There is still significant frictional drag and heating, even for a streamlined, metallic craft designed to travel at hypersonic speeds like the X-15. 60 miles is still considered to be within the Earth’s atmosphere and, even though very rarefied, is not space.’ Some people might call it the ‘edge of space.’

Enter Oberg’s paper thin ‘ice flake’ that supposedly broke off a rear nozzle, then floated forward, and tumbled outside Bob White’s X-15 window. What chance does an ice flake have of surviving in such an environment (60 miles up, travelling about 4000 mph) and doing the things that Oberg claims it could do’? About as much chance as the proverbial snowball in hell

In the real world, a thin, non-aerodynamic sheet of ice like that would have been dragged backward and disintegrated almost instantaneously

Instead of dealing with the science and FACTS, Oberg has to resort to ridicule. You see, it’s not his explanation that’s ridiculous, it’s those ufologists who don’t have enough sense to recognise a true, prosaic explanation, even though it’s scientifically impossible under the actual conditions of the sighting (which Oberg won’t even acknowledge).”
Rudiak concluded by saying, “In Oberg’s response, we find two Klassic staples of debunking technique: l. Any `explanation,’ no matter how stupid or impossible, is preferable to none. 2. Even if a valid objection is raised to the aforementioned ‘explanation’ never admit error. Instead evade, stonewall, ridicule, obfuscate, whatever, such as ‘Do you have any evidence he wasn’t in space’ or ‘Oh, what do you expect of Ufologists — they just never accept a true, prosaic explanation.’” [16]

Ledger made two postings, the first of which brought the issue of a cover-up into the debate. He said, “White’s strained remark about that there are ‘things’ out there seems to be one of those guarded remarks made by someone who has been told ahead of time to not use certain terms over an un-protected radio source. I’m sure that when White saw this ‘thing’ that his knowledge of his own environment., aerodynamics and possibly a fair grounding in physics, would have ruled out a prosaic explanation of the event …. ” [7]

In a second posting, sent soon afterwards, Ledger returned to the dynamic pressure issue, saying, “You would have thought that more consideration would have been given to what this was since it was in close proximity to a vehicle motoring along at 4,000 mph. A sparrow impacting the leading edge of a wing (or windshield) on a light aircraft travelling at only 130 knots can lead to disaster. It always amazes me how these reports get blown-off by the bevy of high priced talent associated with each individual project. Or does it?” [8]

Fleming also made a posting on the issue of dynamic pressure. He wrote that the atmospheric pressure at 60 miles might “actually be about 10 times higher” than what Rudiak had calculated. Based on a speed of Mach 5.45, or about 3,500 miles per hour, he wrote, “The pressure that blowing air exerts on a stationary object is the air density times the square of wind velocity. So the pressure exerted by air 60 miles up against an object travelling at 3,500 mph is equivalent to the pressure exerted by a wind blowing at 14 miles per hour at sea level air pressure.” He added,”That seems too high to allow a flake of ice to appear to hover rather than being swept away, but a more substantial chunk of ice still might hover near the aircraft for a substantial period of time.” He continued to doubt that there would be water to form such flakes, and wrote, “It does seem that the standard ice particle explanation used to explain away all alleged space shuttle UFOs is being forced to fit a very different situation.” [9]

These postings, in turn, led to a number of replies by Oberg on December 2. Of these, two addressed Rudiak’s objections. The first, regarding his comment about spacecraft with “ice flake skins,” Oberg suggested that Rudiak “spend more time reading reality-based books and articles about real aerodynamics and space operations,” rather than “be so overwhelmed by reality-free imaginations.” Oberg noted that the reason meteors are incandescent at 60 miles was due to their high speeds, which he said were around 10 to 20 miles per second. He continued, “The X-15 at its high point is moving at most only a few hundred feet per second.” Oberg concluded by writing, “The fix for this is for you to learn more about the subject, not make fun of ideas you can’t seem to understand.” [10] Regarding a second comment by Rudiak, on the ice flake disintegrating under the high dynamic pressure and temperature, Oberg repeated his comment that the X-15 was travelling at only a few hundred miles per hour. [11]

Concerning Fleming’s doubts about ice forming at high altitude during the X-15′s flight, Oberg noted, “Both around the cryo-tanks and the super-cold propellant lines, ice always formed while the X-15 was on the carrier plane. Atmospheric condensation at those altitudes was common.

Once out of the atmosphere different kinds of jets were fired to point the X-15. They also could have effects on things tucked away in the aft end, for example.” [12] Oberg also said that Fleming’s calculations of a 14 mile per hour equivalent wind speed on the X-15 were based on wrong assumptions about the initial conditions. [13]

Oberg sent a reply to Ledger as well, about the issue of the ice flake drifting in front of the X-15. Oberg noted, “Actually, once exo-atmospheric, the X-15 itself points itself in any random direction using wing-mounted jets. It can do this to point instruments, or for sightseeing, and ultimately to line itself up for re-entry. During this time, even something flaking off its back end can easily wind up in front of the cockpit window as the spacecraft rotates.” [14]

Oberg concluded by sending an e-mail which listed a number of Internet sites and quotations regarding the X-15. In this posting, he said, “…speeds on such missions reached 3,600 mph. Since engine cut-off was about 25 miles, with a vertical rate of 3,600 mph, you can see how at a 32 ft per sec per sec deceleration, the upward fall lasts about 150 seconds and traverses 40 miles straight up. All the way, it’s a ballistic regime and anything coming off the vehicle travels along with it over the arc and back down.” [15]

The believers were quick to challenge Oberg’s statements on the X-15′s speed, flight path, and manoeuvres. Fleming, for instance, noted on December 2, “You seem to be assuming that on its high-altitude flights, the X-I5 was going straight up and then fell straight down, with almost no velocity relative to the ground at the high point of its trajectory.” He continued, “I assumed instead that the plane probably was on a parabolic trajectory, maintaining a hypersonic speed at the highest point.” Referring to a drawing of an X-15 flight which showed such a path, Fleming concluded “…then White’s speed at the highest point in his trajectory, 60 miles up was 3,370 mph, perhaps a little lower due to frictional energy losses. The pressures would still be on the order of a wind blowing at more than 10 miles per hour at sea level. No ice flake is going to hover near the aircraft with those pressures acting on it.” He also added, “These flights lasted less than five minutes, so if something hung around long enough for White to notice it, it must have been visible over a fairly wide range of altitudes. It might have been visible at lower altitudes where the air is denser, not just at the top of his trajectory while White was technically in space.” [16]

Rudiak echoed these comments on a December 3 posting, saying, “This is very strange physics, Jimbo…. According to you, the X-15 had a vertical velocity equal to its total velocity, meaning it would have been travelling straight up!” He continued, “When you make ridiculous statements like this, it just further hurts your credibility as being an aerospace expert. Instead the term ‘pelican science’ starts to come to mind.” Rudiak added that if the X-15 had been flying at only a few hundred feet per second, “…then Oberg’s ice sheet hypothesis might be saved. The effective near-vacuum ‘wind’ at 60 miles would then be reduced by 2 or 3 orders of magnitude from the hypersonic velocities assumed by Lan Fleming and myself.” He continued that “…such low velocities at peak altitude seem to be just more baloney from Jim Oberg, along with his 40 miles and 3,600 mph straight up,”‘ then added “…Oberg probably made up that low velocity figure, perhaps in an attempt to save his ‘ice sheet’ explanation.”

Rudiak also addressed the questions of the X-15′s manoeuvring, and the source of the ice. He noted that Oberg had failed to provide any evidence of extreme manoeuvres, and that it seemed unlikely that White would have manoeuvred very much, as he had to be correctly positioned for re-entry. Rudiak dismissed the possibility that ice formed on the liquid oxygen tank could have been the source of the object. He noted, “After engine burnout, the tanks would be empty. No more ice would form, particularly in the extremely and conditions of these altitudes.” [17]

Rudiak expanded on these comments with a December 5 posting. He said Oberg “…made statements about the X-15 that were so grossly erroneous, no real aerospace expert should ever have made them, no matter how rusty his memory may have been. They were more like embarrassingly erroneous. One wonders if he is even writing his own material anymore.” Rudiak continued with a list of what he called “…the bone-headed errors he (or his shill) made.” These included, Rudiak wrote, claiming that White’s flight reached a top speed of 3,600 miles per hour. “In reality,” he wrote, “it was Mach 6.04 or 4,070 mph, which I determined after only a few minutes search on the Net.” He concluded the listing by saying, “But look at his shoddy performance here: no facts, no science, just error on top of error, some of it no doubt deliberate, trying to bolster his shaky `ice crystal’ theory. He doesn’t sound like much of an expert at all nor someone obsessed with getting at the truth.”

In the same posting, Rudiak repeatedly raised the issue of dynamic pressure. In one case, he accused Oberg of “split hairs about this being ‘space’ and not in the atmosphere. Yes, this was a near-vacuum, but at the X-15 hypersonic speed, there was still significant friction and a breeze blowing. That’s a very important point, one Oberg tried to sweep under the rug, by talking of this being ‘space’ and falsifying the actual velocity of the craft as being only hundreds of feet per second instead of thousands. The effective wind, though not strong, would be sufficient to rapidly sweep away any small, non-aerodynamic debris coming off the craft (which would limit any sighting of such debris to only a few seconds). It would probably also be sufficient to quickly break up any thin sheets of ice into smaller pieces.”

Rudiak suggested that paint chips or metal debris might hold together under such dynamic pressure, but that this, too would still have been blown away by the wind. He also noted that, “The complete tape of Bob White’s flight along with data about the craft when this was all happening (where exactly was it, how was it oriented, and exactly how fast was it going) are all important pieces of information, none of it provided to the royal us.” Rudiak concluded that, “Oberg has basically been caught with his pants down, but he will never admit that he totally screwed up if not deliberately and seriously misrepresented the actual situation… He’s like the school bully copying the class nerd’s quiz, then beating him up later for not getting all the answers right. Do your own damn work, Jimbo.” [18]

Oberg contacted the Edwards AFB History Office, and Dr. Ray Puffer supplied him with the transcript of White’s post-flight debrief The section of the December 6 posting dealing with the sighting is as follows:

After engine shutdown I engaged angle of attack hold at 6 degrees alpha, and I seemed to hold this all right. It wasn’t long after I went through 220,000 that I disengaged angle of attack hold and just continued on over the top. It seemed like a hell of a long time to get over the top…. While I was level I started noticing some things and I said, ‘Now wait a minute they must be inside the cockpit,’ but they were outside the cockpit. It looked like perhaps it might have been residue or frost or very small little things going by. I was paying attention and focusing on what these things might have been, and one time a piece of something about the size of my hand, which looked like a piece of paper, went past just going along with the air plane. It was there, there was no question about it.”

Q: “Do you think it. was frost?”

A: “This thing looked too big for that. It looked like a piece of paper, almost the size of your hand”

Q: “Whereabouts in relation to the air plane?”

A: “Just off to the left side, right on the window level. The other ones were out on the right side, little somethings but I couldn’t distinguish what they were. There was no question about it.”

Q: “Did it come from the nose perhaps?”

A: “Well, I thought the other small ones came from the nose, but this other one just stayed there. Okay, going ahead now, my inertial indicator went above 300,000 ft., but I don’t know how high I got. This looked like I was quite a bit higher than the last flight because I could just look out and — you know what the pictures look like when the guy is flying in orbit, well that’s what it looked like.” [19]
Rudiak replied a few hours later, again stressing the effects of dynamic pressure. He remarked, “The ‘little things,’ assuming they were debris off the nose, I assume would drift along the stream lines and pass within inches of the cockpit windows, which sounds like what White is describing. But how did this other flat thingee get way out there, even if it came off the nose’? It should drift right past the windows along with the little things.”

After noting White’s comment that the paper-sized object seemed too big to be frost, Rudiak wrote, “So why did Oberg claim this was ice? White realised it couldn’t be ice. Furthermore, remember Oberg’s song and dance about this was ice formed from the rearward liquid oxygen tank or fuel lines? Obviously even if ice had survived and then later dislodged, it can’t move forward, one of the major objections to the ice theory from the beginning by the gullible UFO believers.”

Rudiak did not limit his critical comments to Oberg. He had gone to the Edwards AFB History Office three years before to research several reported UFO incidents at the base, and met with Dr. Puffer. Rudiak wrote, “Puffer, like Oberg, is a knee-jerk UFO debunker who loves to laugh at the gullible UFO buffs.” The base logs had no mention of the incidents, as Dr. Puffer had told him beforehand. Rudiak concluded that this showed, “absence of evidence is not evidence of absence,” in that sensitive information would not be mentioned in logs, but be handled through other channels. [20]

As the exchanges with Rudiak were going on, Oberg called Bill Dana, a former X-15 pilot and the retired chief engineer at the NASA Dryden Flight Research Centre. Oberg wrote that “He recalled White’s story well. Bob was concerned, at first, he thought he was flying through a field of these objects going by his window, he told me. Turned out, it was ice coming off something – an APU exhaust, I recall, or some cryogenic transporter.” [211

This, in turn, led to a series of exchanges with Fleming which overlapped the postings by Rudiak. Fleming's first reply raised the issue of a cover-up. He wrote, "Maybe too much time passed between when Duran [sic] was a test pilot and when he was a NASA bureaucrat. His ‘recollection’ sounds more like the spindoctoring of the latter rather than the plain-talking expected from the former.”

Fleming again raised the issue of where the ice might have come from. “Guessing that the acronym APU means attitude propellant unit or something similar,” he noted that the X-15′s thruster rockets used hydrogen peroxide. Fleming continued that they “emitted superheated steam as the exhaust product. It seems unlikely to me that steam would freeze into ice flakes under near-vacuum conditions on surfaces that had been heated to over 1,000 degrees centigrade during passage through the lower atmosphere only seconds before.” He added, “Anything that White saw ‘going by his window’ was moving from the nose toward the tail, and it is not at all likely to have been ice flakes.” [22]

Oberg replied to Fleming’s comments within a few hours. He wrote, “I’m disappointed with your readiness to reject the firsthand comments of people who were right there, with vague allegations of ‘spindoctoring’, a suggestion of deliberate fraud.” Oberg also noted that “APU” actually stood for “Auxiliary Power Unit.” The three APUs on the shuttle burn hydrazine to move the control surfaces and the main engines. He added, that “water vapour is a by-product,” then continued, “Both water and hydrazine freeze readily in space because of robust evaporative cooling, despite sunlight or structural temperatures.” Oberg also added that the X-15′s thrusters also emitted water as a by-product. [23]

Fleming reiterated his conclusion that neither the X-15′s thruster rockets nor its APUs could have produced ice. He wrote, “Since the APUs used extremely hot hydrogen peroxide as fuel, it seems unlikely that their exhaust could be a source of ice for the same reason that the thrusters seem to be an unlikely source of ice. In any case, the APUs were positioned behind the cockpit and ice from that location wouldn’t have got in front of the cockpit.” [24]

In another follow-on posting, Fleming also defended his comments about Dana, saying, “Spin-doctoring isn’t fraud. If it was, they’d have to build more prisons to hold all the bureaucrats and politicians who do it. Dana (sorry about getting the name wrong), said that the object White observed turned out to be ice, giving the impression he’s talking about the results of some investigation, but without exactly saying it. It could not have turned out to be ice because that simply doesn’t make sense.” He concluded that, “Given White’s obvious excitement over his observation, it’s odd that it seems to have aroused so little interest among project scientists.” [25]

On December 8, Fleming sent a posting on his calculations on how an object would behave under the assumed dynamic pressure. He wrote, “If the object was about 7 inches long in the direction of the wind and had a density of around 3g/cc (like some paints) it could have been moved about 2 feet in 5 seconds and 8 feet in 10 seconds by wind pressures equivalent to those of a 10 mph wind at sea level.” Such a speed, Fleming concluded, meant the object would be out of sight from the X-15 in 30 seconds, and its movements would have been easily visible to White from 40 feet away. Fleming concluded they would probably never know what the object was, as “The documentation of any conclusions about the nature of the object reached by X-15 project scientists seems to have gone down the rabbit hole.” [26]

The December 8, 2001 postings marked the effective end of the debate over the X-15 sighting. Personal attacks were made on Oberg for the next week, but these contributed nothing to the question of what had happened on the flight. Ironically, despite the many thousands of words exchanged over the key point in the debate, this was never settled. What exactly was the dynamic pressure on the X-15 at the time of the sighting? To answer this question, we must look at the historical background, and the flight data.

The historical background to Major White’s X-15 sighting began nearly five months before. On February 20, 1962, John Glenn was launched on the first US orbital spaceflight. As his Mercury spacecraft went from the night side of the Earth into daylight on its first orbit, Glenn noticed thousands of very small, luminous particles swirling around the spacecraft. They were moving slowly, at a speed Glenn estimated to be 3 to 5 miles per hour from ahead of the spacecraft, but he did not think they were originating from it. As the Sun rose, the objects became harder to see. Because of their yellow-green colour, Glenn called them “fireflies.” [27]

Some thought they were a natural phenomenon of the upper atmosphere, while others believed the fireflies were paint chips or ice from the Mercury spacecraft. The Soviets soon announced that the second Soviet cosmonaut, Gherman Titov, had also seen fireflies during his August 1961 spaceflight. Titov said that he first noticed them from his booster rocket, and later from the retro rockets. The Soviets dubbed them the “Glenn effect.”

The third firefly sighting was made on April 30, 1962, during an X-15 flight by NASA research pilot Joe Walker, which reached an altitude of 246,700 feet. After the X-15 landed, film from an aft-facing camera showed several fireflies. They were described by a NASA spokesman as “barbell shaped, bright-orange in colour, and passing in groups up to six behind the X-15.” Opinion ranged from “definitely something up there,” to “film spots,” to “sun rays on the lens.”

The Walker X-15 sighting was publicised at the National Conference on Peaceful Uses of Space, held in Seattle on May 10, 1962. When asked at the meeting about the sighting, Walker replied, “I don’t feel like speculating about the nature of these objects. All I know is what appeared on the film in later study. I saw nothing myself during the flight of this nature. From what we can tell, they seem to be disk-shaped, or perhaps even cylindrical. But it’s impossible to estimate their size or their distance from the camera.” Soon afterwards, Paul Bikle, the director of the NASA Flight Research Centre (now the NASA Dryden Flight Research Centre), said, “It was either paint, or frost, peeling from the fuselage and going back.” [28]

Soon afterwards, on May 24, 1962, Scott Carpenter was launched into orbit aboard a Mercury spacecraft. During his three-orbit flight, he also saw fireflies during each sunrise. To Carpenter, the objects looked more like snowflakes than fireflies, and did not seem luminous. They also came in a wide range of sizes, brightness, and colours. Some were white, some were gray, and one looked like a helical shaving from a lathe. They seemed to be moving at different speeds, but were not moving out and away from the spacecraft. At dawn on his third orbit, Carpenter was reaching for an instrument when his gloved hand bumped against the capsule’s hatch. A shower of fireflies then drifted past his window. A second tap on the hatch produced another group, as did a third tap on the wall. The outer skin of the Mercury spacecraft was covered with ice from the water cooling system and/or the hydrogen peroxide jets. This, and not some high-altitude natural phenomenon, was the cause of the fireflies. [29]

Overshadowed by the Mercury orbital flights, the X-15 program continued to fly at higher speeds and altitudes. Walker’s April 30 flight had set a new world altitude record, while Maj. Robert White had become the first man to fly Mach 4, 5, and 6 in a winged aircraft. In early July 1962, White was preparing to set a new altitude record of over 50 miles. The seventh flight of X-15 #3 was planned to have an engine burn time of 80 seconds, which would accelerate it to 5,150 feet per second. This was sufficient for the X-15 to reach a peak altitude of 282,000 feet, at which time it would have slowed to a speed of 4,200 feet per second. The goal of the flight was to make the second test of the MH-96 flight control system. [30] The first three attempts to make the flight had to be aborted after the B-52 took off, due to technical problems. Another attempt was cancelled before takeoff on July 14, due to a request by the Atomic Energy Commission. They were conducting a low-yield nuclear test at Yucca Flat, code-named Small Boy. Not until July 17 was everything ready. [31]

The X-15 was launched from the B-52 at 9:31 a.m., at an altitude of 45,000 feet over Delamar Dry Lake in Nevada. White successfully ignited the rocket engine, and the X-15 accelerated in nearly level flight. After 30 seconds, the X-15 had reached a speed of Mach 2.1, but it was flying at only about 43,000 feet, rather than the planned 53,000 feet. Due to its high speed and lower-than-planned altitude, the maximum dynamic pressure (also called max q) reached about 850 pounds per square foot (psf). White then pitched the X-15 up, establishing a 41 degree climb angle, and engaged the MH-96 pitch hold. The X-15 accelerated upwards, but as it did so, the dynamic pressure dropped rapidly as the air became thinner.

The engine shut down after an 82 second burn (two seconds longer than planned), at a speed of Mach 5.2. The X-15′s altitude was 159,000 feet, but the dynamic pressure on the vehicle had dropped to below 40 psf. White said later at the debrief that he shut the engine down manually, although the log for engine #103 lists a burnout due to fuel exhaustion. In either case, there still was residual liquid oxygen and liquid anhydrous ammonia in the X-15′s tanks. White abruptly went from a 4 G acceleration to being weightless at engine shutdown. The residual propellant was also weightless, and floated in the tanks. After burnout, White engaged the MH96′s alpha hold, and the X-15:
NASA 1: “You’re going higher by our plot than anticipated and this is putting you farther down range.”

White: “Ventral is engaged, speed brakes coming open.”

NASA 1: “OK, looks like you’re about the peak and speed brakes out.”

White: “Roger.” “There’s a lot of things out there.”"Absolutely is!” “What’s my angle of attack’?”

NASA 1: “We don’t have any better presentation than he does. We’re coming back down through, approaching 285. Anticipate a position in correction turn to the right whenever you have the ability to do so.”

White: “Roger absolutely the view.”

NASA 1: “We’re still not getting much on angle of attack.” White: “OK, it’s going to start going back, here we go.” [33]
The X-15′s speed as it reached the peak altitude was about Mach 4.8 (4,500 feet per second). As the X-15 began its descent, its speed again began to increase. The vehicle did not show measurable dynamic pressure until it had descended to about 270,000 feet. To the X-15 program engineers, during this two minute period, the vehicle had experienced zero psf dynamic pressure. The onboard instrumentation was not sufficiently accurate to measure the minute pressure from the residual traces of atmosphere. Nor was any effort made to calculate the dynamic pressure, as it had no importance for the research goals of the flight.

Using atmospheric density tables, it is possible to calculate that the dynamic pressure on the X-15 at maximum altitude was about .02 psf Variations in atmospheric temperature and density would change this by no more than 30%. (The value would therefore range, at most, from .014 to .026 psf. ) The dynamic pressure of a 10 mile per hour wind at sea level is .256 psf. This is at least 10 times greater than the dynamic pressure actually experienced by the X-15 at 314,750 feet. Simply put, the air was too thin, and the X-15 was flying too slowly for there to be meaningful dynamic pressure. An ice flake would not be immediately incinerated or broken up, but rather would remain intact. A low density ice flake would be affected more by the fractional dynamic pressure than the more massive X-15. The relative motion for an ice flake would be just under 3 miles per hour at most. This is much smaller that had been calculated using the 10 miles per hour assumed wind speed. An ice flake would appear to White to be flying more or less along with the X-15, particularly as he had to remain focused on flying the vehicle. [34]

The X-15 was accelerated by the Earth’s gravity as it fell, and as a result, it actually reached its highest speed during the descent — Mach 5.45 at about 120,000 feet. This was equivalent to 3,757 mph, or 5,510 feet per second. During the re-entry, an angle of attack of 20 degrees was maintained, followed by a 5 G pullout. The dynamic pressure also increased as the X-15 descended into thicker air. Max q during the descent reached 1,186 psf, at an altitude of 65,000 feet and a speed of just over Mach 3.7. White glided back to a successful landing at Rogers dry lake. The flight had only taken 10 minutes and 20.7 seconds. [35]

As a result of the new altitude record, Major White was awarded astronaut wings. Air Force regulations then defined ‘space’ as beginning at an altitude of 50 statute miles (264,000 feet). It was not necessary to go into orbit to be considered an astronaut. [36] There were thirteen such space flights made during the X-15 program. A total of eight X-15 pilots exceeded 50 miles; Maj. Robert White (1 flight), Joe Walker (3 flights), Maj. Robert Rushworth (1 flight), Capt. Joe Engle (3 flights), Jack McKay (1 flight), Bill Dana (2 flights), Maj. Pete Knight (1 flight), and Capt. Mike Adams (1 flight). NASA research pilots Walker, McKay, and Dana, being civilians, were not eligible for astronaut wings. [37]

Press attention soon focused on the flight. In its July 27, 1962 issue, Time magazine carried an article on the X-15 program. This included the statement, “But for White and his fellow X-15 pilots, the greatest reward for their work is the satisfaction of probing the mysteries inside the sky. In last week’s flight Bob White found a new mystery for scientists to puzzle over: through the X-15′s thick left quartz window, he saw a strange sight: ‘There ARE things out there,’ he radioed enthusiastically over his voice radio. There absolutely is.”‘ The article continued that it was a slowly tumbling hand-sized object, that Major White thought it was about 30 to 40 feet away, greyish in colour, and that he had no idea what it was. [38]

This was followed in early August, when a group of newspaper reporters was brought to Edwards AFB to see the various research activities, including an X-15 flight. They interviewed White about the sighting, and saw a film of the object from a camera aboard the X-I5. United Press International reporter Douglas Diltz wrote that, “A possibility the X-15 encountered strange phenomena in space arose today with scientists unable to identify a mysterious object….” He quoted a scientist as saying, “It is impossible to explain the object’s presence at this time. As a matter of fact, we aren’t even sure what White saw and the camera photographed were two different objects.” Diltz wrote that the film showed “an object that darted above and behind the plane.” [39]

Another reporter on the trip was James Goodloe, a staff writer with the Birmingham (Alabama) Post Herald. In his article, Goodloe wrote, “White said the object moved gradually toward the rear on the left and was about 30 to 40 feet from the plane. He said he doesn’t know what it was but he said he doesn’t attach any particular significance to it.” The article also had a photo taken from the X-15 film. It showed an irregular white object against a black sky, as it tumbled above and behind the X-15. [40]

Although it is a subjective impression, none of the news articles seemed to hype the sighting, but rather used it to give colour to the story. Diltz also talked about Maj. Robert Rushworth’s low speed/low altitude X-15 flight on August 9th, while Goodloe wrote about the use of F-104 aircraft for landing practice, and described the X-15′s design and shape. The Time magazine article did not use the term ‘fireflies’, but this seemed to be context of the sighting. None of the articles indicate the object was anything more than a natural phenomenon.

The records also do not indicate that either Major White or any of the X-15 personnel attached any importance to the sighting. Major White’s comments about the sighting amounted to half a page of text in a six page report. Although the term ‘fireflies’ was not used in the report, the question asking if White thought the object was frost indicates this is what the engineers were thinking. Although White did not think it was frost, John Glenn also thought the same way. Major White’s report was a detailed description of the X-15′s and MH-96′s behaviour during the flight. He talked about the angle of attack and sideslip measurements becoming inaccurate at high altitude, the view outside the windows, a yaw oscillation he experienced during re-entry, his assessment that if the stability augmentation system (SAS) failed at high altitude, “You can toss in the towel,” the pain in his arm during re-entry due to its cramped position, his concerns about overshooting the lake bed, his comparison of the SAS and MH-96 systems, the difficulty of holding a heading at peak altitude, and similar operational issues. [41]

The X-15 program was a fast-paced effort, with several flights being planned at the same time. It was necessary to quickly analyse the flight data, identify any potential dangers, and incorporate the data into later flights. This was a difficult, time consuming task with only slide rules and mechanical calculators. The yaw oscillation during White’s re-entry was deemed a concern, and plans were made for a later X-15 flight to check this out. The sighting itself was a curiosity which did not affect the research program. UFO believers were interested, however, and the X- 15 sighting was soon incorporated into the belief system.
The debate over the X-15 sighting points out the central role, and usefulness, of the idea of a cover-up to believers

The August-September 1962 issue of The UFO Investigator, the newsletter of the National Investigations Committee on Aerial Phenomena (NICAP), carried a short article on Major White’s sighting titled, ‘AF Criticizes NASA Release of Mystery Object Photo.’ It quoted a letter to a NICAP member from Maj. Carl R. Hart, who was described as the “AF official UFO spokesman.” Major Hart said, “As usual, NASA has gone out on a limb on this,” and added, “The news story was the first intimation the AF had of the problem.” The article stated that NASA scientists “frankly admitted” that they “could not explain the object or its presence in space.” The release of the photo was described as following a three-week investigation and questioning of Major White. [42]

Both X-15 sightings, the initial one on Walker’s April 30 mission and Major White’s sighting, were mentioned in NICAP’s 1964 report, The UFO Evidence, Major White’s sighting was described as being of an object “like a piece of paper” which followed the X-15 for about 5 seconds, and which then “darted above and behind the plane.” [43] The wording was the same as Diltz’s newspaper story on White’s sighting. The X- 15 sighting would be mentioned from time to time over the next four decades, until the postings began on UFO UpDates in late November 2001.

As a case study in the interaction between believers and sceptics, several points can be made. The first has to do with evidence. The believers’ estimate of the dynamic pressure on the X-15 was based on the rate at which atmospheric density drops as altitude increases. As a result, they calculated that the X-15 experienced the equivalent of a 10 to 15 miles per hour wind at sea level. As the postings continued, this estimate became accepted as fact. The believers argued that an ice flake would be quickly swept away and/or be destroyed. Since the object kept pace with the X-15, it had to be anomalous. The estimate they were drawing this conclusion from, however, was based on a rough rule of thumb, and the result was an order of magnitude or more in error.

A related point is how evidence is accepted or rejected. The believers argued that no ice could survive the heat and vibration of the climb, that there were no sources of water to form new ice at high altitude, and no means to freeze it, as the propellants had been completely used up. Oberg argued, based on his experience as a shuttle ground controller, that the hydrogen peroxide used by the thruster rockets and APUs produced water vapour, and that this would freeze in the vacuum conditions. This was rejected by the believers. An additional factor, not recognised by either side, was that even after burnout, there was still propellant in the X-15′s tanks. In many photos of X-15 landings, frost can be seen on the underside of the vehicles. This formed during the approach despite the heating of reentry. Thus there was a means for water vapour to freeze.

A further point is that of research. The postings had to be responded to quickly. There was little time for extensive archival research, and there was a tendency to make “off the cuff” comments – examples of this being Oberg’s statements about the X-15′s low speed at peak altitude and its manoeuvres, and Rudiak’s remarks about meteors burning up at 60 miles and the X-15 not being in space. Oberg contacted the Edwards AFB and Dryden History Offices. None of the other protagonists did so. The majority of the research was done on the web, which has significant weaknesses. Based on web data, Rudiak said that the X-15′s top speed on the July 17, 1962 flight was Mach 6.04. This web data was in error, as the fastest X- 15 #3 ever flew was Mach 5.73. Fleming was correct in saying that the flight’s top speed was actually Mach 5.45, but he had no way of knowing that this actually occurred during the descent, after the sighting, and not during the climb. The critical data, such as the transcripts and the flight data, were not available on the web.

The debate over the X-15 sighting also points out the central role, and usefulness, of the idea of a cover-up to believers. The issue entered the postings almost immediately, and remained throughout. It was used to explain away the lack of any evidence of an extraordinary event. It was used to explain away Dana’s recollections about what had occurred. It was used to explain away the contradiction of a secret sighting of an alien spaceship being freely discussed with newspaper reporters. Finally, it was used to conclude that the truth about the sighting would never be known, as this had been hidden away beyond all chance of recovery by the all-powerful conspiracy and its legions of evil minions. Thus the belief system is preserved.

  1. Filer’s Files #16 1999, archived at under the date April 24, 1999. The email listed regarding this thread are also archived at this URL, on the dates and with the forwarding times listed.
  2. Re: Filer’s Files #48 – 2001 Oberg (November 29, 16:28:55 ).
  3. Re: Filer’s Files #48 – 2001 Ledger (November 29, 23:59:07).
  4. Re: Filer’s Files #48 – 2001 Rudiak (November 30, 22:34:27).
  5. Re: Filer’s Files #48 – 2001 Fleming (November 30, 22:47:17).
  6. Re: Filer’s Files #48 – 2001 Rudiak (December 1, 02:51:47).
  7. Re: Filers Files #48 – 2001 Ledger (December 1, 10:53:40).
  8. Re: Filer’s Files #48 – 2001 Ledger (December 1, 11:08:22).
  9. Re: Filer’s Files #48 – 2001 Fleming (December 1, 15:50:32).
  10. Re: Filer’s Files #48 – 2001 Oberg (December 2, 10:11:44).
  11. Re: Filer’s Files #48 – 2001 Oberg (December 2, 10:18:04).
  12. Re: Filer’s Files #48 – 2001 Oberg (December 2, 10:17:57).
  13. Re: Filer’s Files #48 – 2001 Oberg (December 2, 14:29:27).
  14. Re: Filer’s Files #48 – 2001 Oberg (December 2, 10:21:50).
  15. Misunderstanding The X-15 Ersatz UFO Controversy Oberg (December 2,10:32:06).
  16. Re: Filer’s Files #48 – 2001 Fleming (December 2, 14:29:25 ).
  17. Re: Misunderstanding The X-15 Ersatz-UFO Rudiak (December 3, 06:52:05).
  18. Re: Misunderstanding The X-15 Ersatz-UFO – Rudiak (December 5, 00:27:17).
  19. Re: More On The X-15 – Oberg (December 6, 08:58:34). “Angle of attack,” also called “alpha,” refers to the angle between the airflow and the wing. This measurement is independent of an aircraft’s climb angle. White’s climb angle was 41 degrees (measured relative to the horizon), while the X-15′s angle of attack was 6 degrees (measured relative to the airflow). “Alpha hold” refers to a feature on X-1 5 #3′s MH-96 adaptive flight control system. The pilot could set the angle of attack, as well as the pitch, yaw and roll, and the system would automatically hold it.
  20. Re: More On The X-15 – Rudiak (December 6, 16:30:46).
  21. Re: More On The X-15 – Oberg (December 5, 00:15:48).
  22. Re: More On The X-15 – Fleming (December 5 13:29:55)
  23. Re: More On The X-15 – Oberg (December 6, 15:53:47).
  24. Re: More On The X-15 – Fleming (December 6, 16:16:26).
  25. ..
  26. ..
  27. ..
  28. “X15 Film Shows Mysterious Objects,” Los Angeles Herald-Examiner May 11, 1962, and “Just What Was It X-15 Photographed Way Up There?,” Desert Wings, May 18, 1962. Edwards AFB History Office X-15 newspaper file.
  29. Swenson, et al, This New Ocean, p 452, 453.
  30. X-15 Flight Request Flight No. 3-7-13, X-15 Flight Data Flights 3-1 to 3-15, Dryden ory Office. None of the documents related to the flight were ever classified.
  31. Flight Research Center 1962 Daily Diary, Dryden History Office file # 1-3-10-1 A-6.
  32. X-15 Flight Request, Time history of Mach number, altitude, and dynamic pressure based on radar data for flight 3-7-14, and Beatty radar tracking plot, X-15 Flight Data Flights 3-1 to 3-15, Dryden History Office, and X-15 Research Airplane Flight Record, Dryden History Office file # L1-6-9B-12.
  33. “Altitude Record Flight” pilot transcript, X-15 Flight Data Flights 3-1 to 3-15, Dryden History Office. A segment of this was also posted in Re: More On The X-15 – Oberg (December 7, 09:20:18).
  34. All calculations of dynamic pressure were done by Dr. Kenneth W. Iliff, who was an X-15 research engineer.
  35. Time history of Mach number, altitude, and dynamic pressure based on radar data for flight 3-7-14, and X-15 Research Airplane Flight Record, Dryden History Office.
  36. Dennis R. Jenkins, Hypersonics Before the Shuttle A Concise History of the X-15 Research Airplane (NASA 2000), p 61, 62, 117.
  37. Tim Fumiss, Manned Spaceflight Log New edition (London: Janes 1986) p 15-16, 20, 23-25, 31, 33-34, 43, 46-48, and Robert Godwin, X-15 The NASA Mission Reports (Burlington, Canada: Apogee Books, 2000), 392. Maj. Mike Adams’ astronaut wings were awarded posthumously. During the ascent on his November 15, 1967 flight, an electrical problem and vertigo distracted Adams. As X-1 5 #3 (the same vehicle Major White had flown) reached its peak altitude of 266,000 feet, its nose was pointed 15 degrees to the right. With no significant dynamic pressure on the vehicle, the X-1 5 continued to follow a ballistic trajectory, and there was no change in the flight path. Apparently due to the vertigo, Adams mistook a roll indicator for a sideslip (heading) indicator, and turned the X-1 5 farther to the right until it was 90 degrees to the flight path. It was re-entering the atmosphere sideways. At 230,000 feet, and a speed of Mach 5, the dynamic pressure had increased, and the X-1 5 went into a flat spin. This continued for 43 seconds, at which time the X-1 5 was at an altitude of 120,000 feet and going Mach 4.7. Some combination of pilot action, aircraft stability and the MH-96 control system caused the X-1 5 to recover from the spin. Tragically, the X-1 5 immediately began a pitch oscillation (nose up and down). The MH-96 system was saturated, making the pitch oscillation self-sustaining and increasing in severity. The X-1 5 was descending at 160,000 feet per minute and dynamic pressure was increasing at a rate of nearly 100 psf per second. The g-forces increased to +1- 15 Gs, and, at an altitude above 60,000 feet, the X-1 5 broke up. Maj. Mike Adams was killed in the crash.
  38. Re: Filer’s Files #48 – 2001 Oberg (November 29, 16:28:55 ).
  39. Douglas Diltz “X15 Sky Mystery Grows,” Los Angeles Herald-Examiner (August 9, 1962) Edwards AFB History Office X-1 5 newspaper file.
  40. James Goodloe, “To X-15 Pilot Space Object Still Resembles Paper,” Birmingham Post Herald (August 10, 1962) Edwards AFB History Office X-15 newspaper file.
  41. “Altitude Record Flight” pilot tr•anscript, X-15 Flight Data Flights 3-1 to 3-15, Dryden History Office.
  42. “AF Criticizes Release Of Mystery Object’ Photo,” The UFO. Investigator (August-September 1962), p B. 43. Richard H. Hall, editor, The UFO Evidence (New York: Bames & Noble Books, 1997), p 139.
  43. Richard H. Hall, editor. The UFO Evidence, Barnes & Noble Books, 1997, p.139