Poher Report


1. Basic Information Concerning Minot AFB and the UFO Event

2. Descriptions of the Radarscope Photographs

3. 2-D Analysis of the Radarscope Photographs

4. 3-D Analysis of the Radarscope Photographs

5. The Ionized Cloud Surrounding the UFO

Appendix 1

Appendix 2

Appendix 3


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Analysis of Radar and Air-Visual UFO Observations
on 24 October 1968 at Minot AFB,
North Dakota, USA

Claude Poher, Ph.D.

Part 1. Basic Information Concerning Minot AFB and the UFO Events

1.1 Magnetic Orientation of the Runway at Minot AFB

When I received the following map from Tulien and Klotz, I noticed something peculiar regarding the trajectory of the B-52. In the Project Blue Book documentation the runway heading is referred to as 11 / 29, but should in fact be oriented 110 / 290 degrees from geographical north according to the rules of civil aviation.

Figure 1. Enlarged map with indications added in red. In keeping with U.S. conventions, on this map the borders of the farm properties are denoted by dotted lines, commonly oriented north / south and east / west. We see the trajectory of the B-52 drawn with a standard 180° turn in the upper left corner of the map. However, on this map the trajectory of approach of the B-52 is oriented on true courses 125 / 305° and not on courses 110 / 290° as indicated in the documents. It seems that magnetic and true courses do not match one another.

In Figure 1, the trajectory and traffic patterns around the airport do not have this orientation because 290 degrees is almost directly west, whereas the map indicates a trajectory to the northwest. For comparative purposes I located a map of the Minot international civilian airport. We see that the main runway 13/31 is oriented at true headings of 130 and 310 degrees, which conform to the trajectories in Figure 1. The second short civilian runway 08/26 is oriented at 080 /260 degrees true. Therefore, the prevailing winds in the region are oriented 130/310 degrees. An online search located the following regional map showing the position of Minot AFB in relation to the city of Minot, ND.

Figures 2 and 3. Location of Minot International airport and Minot Air Force Base 13 miles north on Hwy. 83; and diagram of the international airport at Minot, ND. Source: Wikimapia, and Minot International (MOT).

Based on the scale of the map, Minot AFB is located 13 miles (21 km) north of the city of Minot, ND. Even though it is unlikely that prevailing winds are different between the two airports, I nevertheless checked wind conditions. Another online search was more difficult, likely because Minot AFB is still a strategic airbase with nuclear missiles on alert. On a web site devoted to civilian pilots I located a simplified air view of the base, in which the runway is clear and the confidential installations are not indicated.

Figure 4. Map providing an aerial view of Minot AFB.

What is apparent is that there is only one runway at Minot AFB. When we compare the course of this runway to the cross rulings, we determine 115 / 295 degrees, which corresponds to information in the documents. Note also that the roads on the map are parallel to the cross rulings, which means that they are oriented N-S / E-W, as is customary in the USA, however, it is curious that the cross rulings are rectangular. By American standards, cartographic cross rulings are generally square with every square measuring one or two statute miles per side [a statute mile is equal to 1609 meters, not to be confused with a nautical mile (nm) which is 1852 meters]. It is also unusual that the runway is not at right angles with the taxiways. I therefore adjusted the pixel scale of the map and corrected the cross rulings.

Figure 5. Drawing of Figure 4 modified in height.

The adjusted map in Figure 5 shows that the runway approaches are at right angles to the cross rulings and the written indications seem adequate. The orientation of the runway is actually 125 / 305 degrees true, which corresponds to the neighboring international civil airport and the orientation of the trajectories of the map in Figure 1. Later, I confirmed this with another map of Minot AFB forwarded by Tulien and Klotz. On this particular map the cross rulings are in statute miles; N-7 is indicated, and the position of the UFO at the time of the B-52 flyover is plotted.

Figure 6. The area of observation with cross-rulings oriented NS / EW in statute miles. The orientation of the runway is exactly 125 / 305° true. The two positions of the stationary UFO (landing sites) are from the documents: “TACAN, 320 radius, 16 nmi” (Memo, 1 Nov. 68a, 1); and map grid “AA-43” (WSC summary). Site #1 is also the general location of the UFO observed for over an hour by personnel at N-7.

Finally, I located an aerial photograph of Minot AFB, which further confirms the accuracy of the previous maps.

Figure 7. Satellite photograph available from: Minot Air Force Base.

1.2. Additional Radar Systems at Minot AFB

According to the account described in the Blue Book documents, only the B-52 onboard radar and a weather forecast radar system detected the UFO. I find this difficult to accept since Minot AFB was a principal Strategic Air Command base with fifteen B-52 nuclear bombers and 150 Intercontinental Ballistic Missiles (ICBM) on constant alert. It is hard to imagine that in such an environment at the height of the Cold War there were no surveillance radars that detected potential enemy planes, incoming missiles, or for that matter, UFOs. Nonetheless, for lack of additional documentation, we must content ourselves with the radarscope photographs filmed onboard the B-52.

1.3. The Two-Mile Jump of the UFO

The Blue Book documents indicate that near the completion of the 180-degree turnaround over the TACAN initial approach fix (colloquially referred to as the WT fix) the B-52 radar operator observed the UFO on his radarscope and noted its distance at 3 nm (5550 meters) to the left of the aircraft. However, during one 3-second sweep of the radar, he noted that the UFO was now located at a distance of only 1 nm (1852 meters), still to the left of the aircraft. According to the map in Figure 1, the UFO would have then remained at the same distance and relative position pacing the B-52 for the next 38000 meters (23.6 mi.). The average distance between the B-52 and the UFO along the parallel trajectories is actually 1930 meters (1.04 nm), which is relatively close to the 1 nautical mile stated in the documents.

Figure 1 also shows two successive radar positions of the UFO in relation to the B-52, which are indicated by two crosshairs (x) in the upper left corner near the WT fix. The distance between the position of the UFO and the aircraft along the dotted lines is exactly 6100 meters. As a result, the UFO would have moved from 6100 to 1930 meters, traveling 4170 meters towards the B-52 in less than three seconds. According to Newton’s law, the most reasonable proposition would assume an equal acceleration and deceleration, and would therefore have to be made in two steps.

Acceleration (A) is simple to calculate:

In the course of this very strong acceleration, the speed (V) attained by the UFO was at maximum velocity in midcourse:

These preliminary results suggest that at the very least the crew of the B-52 should have heard a loud sonic boom; yet no such sound was actually reported (as is often the case with UFOs). As we will eventually see, it also appears that the UFO had sufficient power to achieve an acceleration that would theoretically allow an interstellar voyage.

It needs to be noted that the speed provided in the documents by the Minot AFB officer in charge of the investigation, Col. Werlich, of 3000 mi./hr (4827 km / h) appears wrong, possibly because the necessary two steps of acceleration and deceleration were not taken into account (4170 m in 3 seconds = 5004 km / h; or 3109 mph). Moreover, if both of the crosshairs drawn on the Figure 1 map for the position of the UFO are weather radar positions, then the acceleration would be higher, because the UFO jump represented by a segment of the trajectory in Werlich’s overlay has a length of 6400 meters. This would correspond to:

The maximum speed would then be 4266 m/s, equal to Mach 12, or 15000 km / h (9321 mph). As we will see by analyzing the actual radarscope photos taken onboard the B-52, the speed of the UFO and its acceleration can be calculated more accurately by using less controversial methods.

1.4. The UFO Landing Zone

The position of the rectangle, drawn by Werlich on the overlay map indicating the “probable area of aircrew ground sighting,” is shown in Figure 8. This is the area where the B-52 pilots observed the UFO on or near the ground during the flyover at low altitude. Also indicated are two other landing site locations provided in the Project Blue Bock documents.

Figure 8. The three indicated landing locations of the UFO.

The cross rulings on this map are in statute miles and equal 1609 meters. The coordinates of the landing area situated to the northeast of Grano, ND, are relative to the Deering TACAN transmitter adjacent to the runway at 37% of the length from the northwest end. Werlich indicated the landing area as being 16 nautical miles (29.6 km) from the TACAN transmitter at 320 degrees radial. How this position was obtained is not stated in the Blue Book documents, however, it is possible that there is an error in the 320 degrees azimuth as a result of confusion between the magnetic and true azimuth.[2] The difference would be 334 - 320 = 14 degrees, which is close to the 13 degree magnetic declination for Minot at the time. The northwest landing area (AA-43) is indicated from its coordinates on the grid map. This location is provided in the documentation in the summary that was apparently prepared and submitted by the 91st Strategic Missile Wing, Security Controller. The original source of this information is not specified.[3]

1.5. The Two VHF Transmission Failures

During the two occasions when the B-52 was in close proximity to the UFO, the B-52 VHF radio transmission with Radar Approach Control (RAPCON) was interrupted, while the reception of incoming communications was unaffected. These communications took place on a stated UHF military frequency, although they were actually in the VHF band at 270 Mhz.[4]

The first loss of radio transmission occurred near the WT fix, at the time when the UFO closed on the B-52’s left wing, reducing its distance from 3 to 1 nautical mile (nm). The loss of transmission continued for more than 16 nm, or about 4 minutes, if the airspeed of the B-52 during the descent to the runway was 250 knots (460 km / h, or 285 mph). This speed is plausible because the B-52 was descending from 20,000 to 3200 feet. As soon as the UFO disappeared from the radarscope, VHF communications returned to normal.

The second instance occurred when the B-52 was at its closest proximity to the UFO during the flyover at 4:35 (CDT), at an altitude that was less than 1 nm.[5] In both instances, neither the onboard instrumentation, nor the radio reception appeared to have been affected. Taken together, these two VHF transmission failures pose an interesting physical effect that will be examined in more detail later in this study.

Even though we have witness accounts and post-event interviews of the UFO observation, we should note that these accounts are not always concomitant with the physical data. Because the UFO observation provides us with exceptional physical evidence, specifically 14 radarscope photographs, as well as transcriptions of radio communications between the RAPCON ground controllers and the B-52 co-pilot, we shall rely primarily on this physical evidence in our following analyses.

1.6. Observer Accounts of the UFO Events

Numerous ground witnesses at various locations, as well as the B-52 pilots, observed the bright luminous UFO and reported its movements over a period of three hours. Eight witness accounts are presented in Appendix 3: Observer Accounts of the UFO Events From the Documentation, seven of which are extracted from the Project Blue Book AF-117 Sighting of Unidentified Phenomena Questionnaire. During the Blue Book investigation, the B-52 pilot Major James Partin also completed the AF-117. Partin was not a regular crewmember, but was onboard during this particular mission being evaluated by the B-52 aircraft commander, Captain Don Cagle. None of the six regular crewmembers, including copilot Capt. Bradford Runyon, were interviewed during the Blue Book investigation. However, Thomas Tulien for the Sign Oral History Project (SOHP) recorded interviews with Runyon on 5 May 2000, and 25 February 2005, and extracts from the transcripts have been included in Appendix 3. Rather than a chronological narrative of the events, the documents provide a database of the various witness accounts.

1.7. The Question of the Stars Sirius and Vega

In his final report, Quintanilla concludes that during the sighting period the ground witnesses were either viewing a celestial object or the B-52, and that the pilots could have been observing Vega during the air-visual observation.

“The ground visual sightings appear to be of the star Sirius and the B-52 which was flying in the area. The air visual from the B-52 could be the star Vega which was on the horizon at the time, or it could be a light on the ground, or possibly a plasma.”[6]

In other words, for over three hours on this particular morning, at least 18 witnesses were unable to distinguish a common celestial object, and/or a B-52 on a routine flight path (with and without its landing lights on). We should keep in mind that it was quite typical of Blue Book to ignore witness reports and relevant empirical data, presumably because the reported phenomenon does not support a conventional explanation. Be that as it may, let us explore the final conjecture made by Quintanilla that the observed phenomenon was indeed a star. The two possible stars suggested by Quintanilla are Sirius and Vega, which were visible during the sighting period and most prominent in order of brightness. The Minot AFB coordinates I have used are:

Following are the positions of the stars Sirius and Vega at the time of the observations on 24 October 1968.[7] Azimuth (Az) is ascertained from the geographical north in a clockwise direction, and altitude (alt) corresponds to the height above the horizon. These are the star positions during the initial observation by Smith, Isley, and O’Connor at 2:30 a.m. (CDT; 07 h 30 Z [GMT]).

As a result, Sirius was in the southeast sky (rising to its culmination in the south), and VEGA in the northwest sky (descending to below the horizon in the north). But Isley and O’Connor reported their initial observation of the UFO in the east, while traveling south towards N-7, which does not correspond to the directions of either star. In addition, let us not forget that at least 18 witnesses reported the angular size of the UFO in the order of 23 to 70 minutes of arc according to the location of observation. By comparison, the angular size of the moon is about 30 minutes of arc, so these reports do not correlate to a point star with a null angular size.

Let me point to additional data that further disprove that the object could have been a star. 09 h 28 Z (4:28 a.m. CDT) is the time of the fly-over and air-visual observation of the UFO from the B-52.

These data clearly show that VEGA was in fact not even visible to the B-52 pilots at the time of the reported observation. Also, the B-52 flew directly towards the UFO on a heading of 290° (WNW), and VEGA (at more than 340°) would have been to the right of the aircraft.

In the Blue Book final report, Quintanilla documents the positions of the stars at 08 h 00 Z (3:00 a.m.) as follows:

However, these results are clearly inaccurate since the altitude angle of culmination of a star is determined by: alt = 90° - latitude + declination. The culmination of Sirius at Minot AFB at the time of the observed phenomenon was:

The altitude of Sirius could not have exceeded to 28° as stated by Blue Book. It is possible that their astronomical calculation reflects an incorrect latitude value by 3.16° towards the south, which is a position error of 350 km for Minot AFB. For 08 h 00 Z, with the coordinates for Minot AFB we actually find:

Screen captures of the positions of Sirius (2:30-5:30) and Vega (2:30-4:30) from the perspective of the observers at N-7 during the times of the observations are available here:

The view of the southeast horizon from N-7. During the times of the UFO observations on 24 October 1968, the star Sirius was ascending to the right. Bear in mind, if the reported overcast from 9,000 to 25,000 feet also extended to the south; it is unlikely these stars would be visible. For example, Smith at O-1 noted in his AF-117 that it was “completely overcast” and no stars were visible (4).

The view of the northwest horizon from N-7, during the times of the UFO observations on 24 October 1968. The star Vega was descending below the horizon to the right.

2. Descriptions of the Radarscope Photographs ››