Culprits of Lockerbie a treatise Concerning the Destruction
The proof that PT35b did not come from
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- Feraday agrees with Thurman on visual match between PT/35b and Thüring MST-13 mother boards
- Fereday wrongly asserts a complete match on materials ( ie
- Feraday’s strange - and strained - conjecture to explain the difference
- Unexplained anomalies in notes on control sample timer DP/111
- Fereday overreaches himself still further
- PT/35b distinguished from Thüring boards by Owen Lewis’s visual examination
- Corner cut-outs
- Commentary on the visual comparison by Owen Lewis
- Possible explanation: that the heat of the explosion had boiled off the lead constituent of the PT/35b alloy coating
- Expert recommendation for testing
- Abortive defence steps during Zeist
- Possibility that Thüring produced boards with different types of circuit coating
- SCCRC supplementary report
- The defence get an answer from Thüring: all their MST-13 boards had tin-lead alloy coatings
- The inference: if PT/35b was unchanged by the blast it could not have come from a Libyan timer
- Propositions revealed by the blob of solder on the fragment’s “1” shaped relay pad
- Tests carried out to determine if the heat generated by the explosion could have evaporated any lead content of the tin-lead alloy coating
- Conclusion 1 : PT/35b had been manufactured with pure tin coating
- Conclusion 2 : PT/35b could not have been manu-factured for Mebo by Thüring
- Additional finding : PT/35b was probably a DIY production
7. The proof that PT35b did not come from a Mebo board supplied to Libya (a) Original RARDE work on PT35b following the FBI match Sample exhibits provided by Mebo As already mentioned it was in mid-November 1990 that the Dumfries and Galloway police team visited Mebo’s offices and obtained MST-13 timers and numerous circuit boards. This was at the behest of the Swiss federal prosecutor’s office and the items were handed over by Edwin Bollier in person on 16 November. They included:
RARDE had also been furnished with the MST-13 acquired by the BATF in Togo and handed on to the CIA. It was given exhibit reference DP-84. Exhibit DP/347(a) was apparently chosen for analysis because, like PT/35b, it had solder masking on the reverse side only (and was therefore from the first batch of 25 supplied by Thüring) and had corners cut out. Feraday agrees with Thurman on visual match between PT/35b and Thüring MST-13 mother boards As already mentioned, James Thurman had asserted that PT/35b and the board he used for comparison (whichever it was, whether the diecast Togo MST-13 timer with marks where the corners would have been cut out, or one with corner cut-outs from a boxed MST-13 which the CIA must have had available) were “as alike as two thumbprints”. In due time, working on the fragment in the RARDE laboratory and comparing it with DP/347(a), as well as with the MST-13 timers DP/111, DP/100 and DP/84, Feraday endorsed Thurman’s opinion. In the RARDE Joint Forensic Report (signed off in December 1991) he stated– “The particular tracking pattern of the fragment has been extensively compared with the control samples of the MST-13 timers and circuit boards (items DP/111, DP/84, DP/100 and DP/347(a)) and it has been conclusively established that the fragment materials and tracking pattern are similar in all respects to the area around the connection pad for the output relay of the MST-13 timer. . . . The conducting pad and tracks present on the fragment PT/35b are of copper covered by a layer of pure tin” (para 7.2.1; reiterated at trial, 13 June 2000, transcript, p.3172). Visually, of course, Feraday was correct. Making due allowance for the fact that the corner cut-outs on boxed timer mother boards were made by hand the fragment and DP/347(a) did appear, at least to the naked eye, to be identical in configuration (see sub-para (a) next, for further detail). Fereday wrongly asserts a complete match on materials (ie as to their chemical constitutents) between PT/35b and control exhibit DP/347(a), clearly knowing this to be incorrect It is to be noted, however, that Feraday did not confine the language of his assessment to a visual match. He had stated categorically that the “fragment materials and tracking pattern [were] similar in all respects”. This had to be taken to include the chemical make-up of materials in the fragment but his assertion is belied by documents only disclosed shortly before al-Megrahi abandoned his appeal in 2009. The documents contain data from metallurgical tests conducted on PT/35b and DP/347(a) and were annotated in Feraday’s own hand. In one note he wrote that the coating of the tracks on PT/35b is of “pure tin” and in the other he recorded that the coating of the tracks on DP/347(a) was approximately “70/30 SN/Pb”, that is 70/30 tin to lead (RARDE documents PT/82 and 88). Both notes were initialled by Feraday and dated 1 August, 1991, that is four months before he signed off the Joint Report, in which the constituent materials were said to be identical. To make the point very clearly, in spite of the fact that in Feraday’s memorandum of 1 August 1991 (not disclosed until 2009) he asserted that the chemical make-up of the coating was different – pure tin for PT/35b but tin/lead for DP/347(a) – in the Joint Report four months later he contradicted himself in asserting that in terms of materials they were “similar.” As John Ashton observes, had the newly released documents been disclosed before the trial they would have provided the basis for robust cross-examination of Feraday (Megrahi, p.361). Feraday’s strange - and strained - conjecture to explain the difference In his memorandum of 1 August, 1991, Feraday sought to offer an explanation for the differences by suggestiong that the tin/lead alloy coating on DP/347(a) may have been applied on top of a layer of pure tin either by dipping or by rolling. He offered no evidential or circumstantial basis for this imaginative conjecture which was probably intended to imply that a tin-lead alloy top coating on PT/35b might have been removed by the explosion. In the event, the explanation was not pursued, probably because an independent expert engaged by the police came up with a modified theory (see further below). In any event Thüring’s production method categorically involved no such procedure, which is believed to be unknown in the industry. The attempted explanation is significant in one very important respect in that it clearly demonstrates Feraday’s acute awareness of the difference, as to the tin-coating, between the fragment and the control sample and excludes any realistic likelihood of innocent oversight when he formulated the unequivocal terms of his assertions in para 7.2.1 of the Joint Report. Unexplained anomalies in notes on control sample timer DP/111 Describing DP/347, the four identical mother boards obtained by the police from Mebo on 16 November 1990, the Joint Report (para 7.1.4) stated– “All four circuit boards are essentially similar in tracking pattern, colour and materials to the green coloured control panels/circuit boards present upon the three MST-13 control sample timers described above as DP/111, DP/84 and DP/100.” Feraday’s note on DP/111, dated 4 July, 1991, describes the tracks of its mother board as copper etched on to the underside coated with a layer of pure tin, although curiously the adjective “pure” was inserted in front of the word “tin”. No test results were cited to verify the description but the Joint Report not only contains no reference to the dissimilarity between DP/111 and DP/347(a), which an objective report would surely have demanded, but is entirely silent too about the content of the coating. If indeed it had been pure tin this would doubtless have been something well worth mentioning in the Joint Report, having regard to its correspondence with PT/35b. If it had in reality been pure tin why was this not mentioned in the Joint Report, given that it would have supported the prosecution case that the fragment came from a Libyan MST-13? The obvious answer which suggests itself is that RARDE eventually realised that the coating could not have been pure tin, or at least that DP/111 had not in fact been tested. Why then was the adjective “pure” inserted in Feraday’s undisclosed note on DP/111? It seems likely that the plain word “tin” was originally used in the note merely because of the common practice in the electronics world of using that word to connote coating with either pure tin or a tin-lead alloy. Perhaps when Feraday checked his note later and re-read the word “tin” he assumed he had meant pure tin, or perhaps it was wishful thinking, having regard to the nature of PT/35b, and he therefore inserted the adjective “pure”. Later when it became clear that all the Thüring boards were coated with a tin-lead alloy, the insertion became an embarrassment and no further reference was made to it.
“the same pattern of tracks will not occur on any other electronic product, only the Mebo brand MST-13 type timers” (joint report, para 7.1.1; trial evidence, 13 June 2000, p.3139). As will be seen later that this statement was hardly justified but his blithe confidence seems to have infected the diligence of the police. (b) Bollier’s red herring Bollier challenges the contention that PT/35b was part of a Thüring board in an MST-13 supplied by Mebo to Libya It has already been mentioned that Edwin Bollier claimed that the fragment in the photograph he had originally been shown by police and which he said he understood from them had been recovered from the Pan Am 103 wreckage was greyish-brown, and was not PT/35b (see Ashton, Megrahi, p.80). There was of course absolutely no evidence to substantiate his allegation but while it may be right to treat it with care it is of note that he also professed to avow that from the photographs of PT/35b he was shown (never having been permitted to examine the actual exhibit) he was confident that it was distinguishable in appearance from the counterpart portion of the Thüring machined mother boards in timers supplied by Mebo to the Libyan military. In particular he claimed he could assert that it was handmade because the curved edge of the fragment was rough. Lumpert’s prototypes, he pointed out, were cut by hand with a hacksaw. Bollier’s contention was cited by Ashton and Ferguson in Cover Up of Convenience (at p.234) but, as has already been mentioned, at the time of writing that book it was believed by the authors that the curved cut-outs were machine-stamped at Thüring (personal communication from John Ashton). However, it is now known that the corners were in fact cut out at Mebo by hand. PT/35b distinguished from Thüring boards by Owen Lewis’s visual examination While Bollier’s input on the visual comparison between PT/35b and the Thüring boards may have been no more than an unhelpful chimera a photograph of PT/35b was subjected well before the trial at Zeist to expert visual comparison with one of the complete machine-made boards. In 1998 the Channel 4 Dispatches programme commissioned Owen Lewis, a military explosives forensic expert, to examine a photograph of the fragment with that of one of the Thüring machined boards (A&F, p.234). Chiefly for the following reasons he found that the two items were dissimilar:
Commentary on the visual comparison by Owen Lewis A simple evaluation of the Lewis conclusions may be made by perusing the photographs in Figure 6, below. It is self-evident that the two pictures of PT/35b depict the fragment at different stages in the process of testing, that on the right clearly being taken later, that is after the section DP/31 was cut from it. Moreover, it is clear that the top edge of the fragment, as depicted in the picture on the right, had been cut away or otherwise removed during the testing process. This was in fact DP/11, described as a “tiny sliver” which had been removed in 1990 in order to analyse the make-up of the laminate. (See the account by Ashton, at p.151, of the acrimonious correspondence between SIO Stuart Henderson and Feraday regarding DP/11.) The effect of the removal of the sliver was to shorten the upright of the “1” shaped touchpad and altered its proportions. But a comparison between the top edge of the “1” in the control sample DP/347(a) and that of the earlier image of PT/35b shows that the top edge of the “1” slants downwards from right to left at exactly the same angle. It is true that the angle and curvature of the cut-out to the right of the “1” differs as between PT/35b and DP/347(a) but that can surely be explained by the fact, as is now known, that the cut-out was not machined by Thüring but undertaken at Mebo by hand use of a hacksaw, with the job presumably being carried out by Lumpert. Some slight variation of the hand-wrought cut out, board to board, was only to be expected, allowing for which the conclusion to be drawn is that there was no relevant visible difference between PT/35b and the DP/347(a). Visually, at any rate, PT/35b could have come from a boxed Mebo MST-13 timer. Chemically, however, as will be seen, the story is rather different. It seems that not all the mother boards had the corners cut. As already mentioned, the Togo timer, an unboxed example, bore a mark where the cut would have been. 
Fig. 8 (c) Developments up to al-Megrahi’s second appeal Independent expert noted a key difference in the tinning between PT/35b and the MST-13 motherboard obtained from Mebo It has been noted that when in the first half of 1990 the experts consulted by the police built up a profile of the PT/35b fragment it was established that its copper circuitry tracks were coated with a layer of pure tin. Two years later, and a year after Feraday’s undisclosed notes on the metallurgical tests pointed out the contrast between the coating of the tracks on PT/35b and that of DP/347(a), the police went back to the original experts and now sought a comparative analysis of PT/35b and DP/347(a), the latter not being available when they were originally consulted. The two experts consulted, Dr Rosemary Wilkinson, a metallurgist at Strathclyde University, and Dr David Johnson, a Manchester University materials scientist, predictably each established that whereas the circuitry coating of PT/35b was pure tin, that of DP/347(a) consisted of a tin and lead alloy. Possible explanation: that the heat of the explosion had boiled off the lead constituent of the PT/35b alloy coating Both experts suggested a possible explanation for the difference, conjecturing that it might be attributed to the heat of the explosion. This was always assuming PT/35b had “survived a close-range explosion involvement,” to use Dr Hayes’s phraseology describing the Toshiba RT-SF16 instruction manual cover, exhibit PK/689. In fact there was nothing in the reports of either Wilkinson or Johnson to indicate that PT/35b had been involved in a bomb blast (a point made in a report by Dr Dennis Ryder, an expert consulted by the defence before trial who was not in the event called as a witness: see Ashton, Megrahi, p.357). Given that lead has a low boiling point Wilkinson suggested that if the original coating of PT/35b had, like DP/347(a), been a tin and lead alloy, the heat of generated by the explosion might have boiled off the alloy’s lead constituent. Expert recommendation for testing Dr Wilkinson advised that her hypothesis needed to be tested experimentally. Recommendation for further testing disregarded by the police The disclosed paperwork reveals nothing to suggest that the police took any action to pursue Dr Wilkinson’s recommendation. Abortive defence steps during Zeist In contrast with prosecution inaction years earlier, after the start of the trial at Zeist the defence did take some steps to follow up Dr Wilkinson’s recommendation. This involved asking Dr Dennis Ryder, an expert with the forensic science agency Capcis, to comment inter alia on her report but he proceeded to tackle the more fundamental question of whether the fragment had actually been involved in an explosion, noting that Wilkinson had said nothing to indicate that it had been. Since, however, both Allen Feraday and the defence forensic expert, Gordon McMillen, appeared to be in no doubt that it had been through an explosion, or at least assumed that it had been (though on what direct evidence remains unclear) the defence chose not to rely on Dr Ryder. The result was that the boiling away of lead hypothesis remained untested. Possibility that Thüring produced boards with different types of circuit coating Rather than that the lead in the coating on PT/35b might have boiled away during the explosion it remained possible that there was a more straightforward explanation of the difference in coating constituency as between PT/35b and DP/347(a). This was that Thüring may have coated the circuitry on some of the MST-13 boards with pure tin while coating others with a tin-lead alloy. Urs Bonfadelli, Thüring’s production manager, referred in his precognition statement to the circuitry being “tin-plated” (30 March, 2000) and at trial he said that the “trackings were in tin” (16 June, 2000; transcript, p.3413). However, although he provided a detailed account of the manufacturing process (transcript, pp.3402-3443) he was not asked by either side whether the coating of the MST-13 boards produced by the company were exclusively tin-lead alloy or whether the company produced some of that kind and some with pure tin coating. SCCRC supplementary report In their supplementary report the SCCRC accepted the untested Wilkinson-Johnson hypothesis that the absence of tin in the PT/35b coating may have been attributable to its having been involved in the explosion but decided that in any event the issue appeared to have little significance. It seems that they took this view because they noted that in stating that the tracking was in tin Urs Bonfadelli made no mention of lead and they concluded that this was consistent with the tracks having been coated with pure tin on all the Thüring MST-13 boards. However, what the Commission failed to appreciate was that within the electronics industry “tin” can mean not only pure tin but can also be shorthand for a tin/lead alloy. (d) Science finally solves the riddle: PT/35b did not come from any of the timers supplied to Libya The defence get an answer from Thüring: all their MST-13 boards had tin-lead alloy coatings Preparing for al-Megrahi’s second appeal his solicitors asked Urs Bonafadelli the obvious question whether the MST-13 boards were coated with pure tin or a tin/lead alloy. The answer was unequivocal. All were coated with an alloy of 70 per cent tin and 30 per cent lead and Thüring only ever made circuit boards with such a coating; pure tin coating required a completely different process which the company had never used (statement to John Ashton, 23 October, 2008). The inference: if PT/35b was unchanged by the blast it could not have come from a Libyan timer The inference was irresistible and finite. It meant that if the coating on PT/35 had not been altered by the explosion as a result of the alloy’s lead content being boiled away by the heat so generated the fragment it could not have been coated with an alloy of tin and lead. It could not therefore have come from any of the timers supplied to Libya. Experts instructed To obtain an answer whether the lead in a tin-lead alloy could have been boiled away in the heat generated by an explosion solicitors acting for al-Megrahi (Taylor and Kelly) sought opinions from two independent experts, Dr Chris McArdle, a specialist in microelectronics and nonatechnology and Dr Jess Cawley, a metallurgist. Propositions revealed by the blob of solder on the fragment’s “1” shaped relay pad McArdle and Cawley agreed with the Crown’s experts that what appeared to be the imprint of a piece of wire in the blob of solder on the “1” shaped relay pad indicated that an electronic component had once been attached and between them they ventured the following propositions: (i) the imprint indicated that the solder had never been hot enough to melt because otherwise it would have flowed across the pad and the imprint would have disappeared; (ii) self-evidently a metal will not evaporate before it melts; (iii) since electronic solder is a tin and lead alloy if the solder had never been hot enough to melt, the lead content could not have evaporated away; (iv) if the lead had not evaporated away from the solder it could not in theory have evaporated away from the alloy coating of the circuitry; (v) plastic explosive of the type used in the Lockerbie bomb produce a flash of intense heat; (vi) as with most metals, lead requires a far longer exposure to high temperature before it will melt, let alone evaporate. Tests carried out to determine if the heat generated by the explosion could have evaporated any lead content of the tin-lead alloy coating A series of experiments were conducted to test the validity of these propositions. A number of boards were fabricated to Thüring’s circuit diagram for the MST-13, some with tin-lead circuitry coating and others with pure tin. A blob of solder was applied to a number of the boards in the same position as that on PT/35b. The boards were scanned with an electronic microscope to confirm the metallic content of the coating. On placing some of the boards with solder blobs in a furnace it was established that the solder took four seconds to melt, plainly far longer than PT/35b would have been exposed to extreme heat had it been in an explosion. The exercise was repeated with some of the tin-lead coated boards with no solder blobs and analysis of the coating using the scanning electron microscope revealed that there had been no change in the constituents of the coating from tin/lead to pure tin. Conclusion 1: PT/35b had been manufactured with pure tin coating The conclusion of the tests was that the explosion could not have changed the circuitry coating of PT/35b from a tin-lead alloy to pure tin and that it must therefore have been manufactured originally with a pure tin coating. Conclusion 2: PT/35b could not have been manu-factured for Mebo by Thüring It followed that PT/35b had not come from a board manufactured for Mebo by Thüring. Conclusion 3: PT/35b could not have come from a board in any of the 20 timers which Bollier asserted had been supplied by Mebo to Libya Finally, it was clear that PT/35b could not have come from a mother board in any of the 20 timers which Edwin Bollier asserted had been supplied by Mebo to Libya. Additional finding: PT/35b was probably a DIY production In his report Dr McArdle noted that the tin coating on PT/35b was very thin, suggesting that the board was probably made using a process known as immersion tin, more commonly employed in ad hoc or “DIY” production than in commercial manufacture. The strong suggestion is that it was counterfeited by some person unknown. (e) Governmental inspired response Following – and possibly as a result of – the McArdle-Cawley findings the Government of Scotland granted Abdelbaset al-Megrahi compassionate release for his life sentence on the ostensible grounds that he was suffering from terminal prostate cancer. The decision seems to have been conditional on al-Megrahi abandoning his second appeal against conviction, so the Crown were never required to submit themselves to the public ordeal of attempting to support his conviction in the wake of the new evidence. The findings reached the public domain with the publication, on February 27, 2012, of John Ashton’s eagerly awaited book Megrahi: You Are My Jury (see pp.354-359). Asked by the producers of the BBC Scotland and Al-Jazeera documentaries aired on the day of publication to account for the contrast between the pure tin coating of PT/35b and the tin-lead alloy coating of DP/347(a) Vicky Torraca, the DSTL public relations and media manager, forlornly attempted to resurrect Feraday’s long lost conjecture in his undisclosed notes. It was quite possible, she explained quoting Feraday, that DP/347(a) had a coating of lead and tin which had been “added (by dipping or rolling) over the top of a track of copper coated with pure tin.” The explanation also found its way to the national press, DSTL being quoted as claiming that “coatings can be modified” (see Severin Carrell, The Guardian, February 27, 2012). In her response to the documentary makers Ms Torraca sought to stress that the control samples supplied came in a variety of configurations and she cited Feraday’s note about DP/111 having a coating of pure tin. As has already been discussed Feraday’s note that DP/111 was pure tin coated is highly suspect and, as we now know, the Mebo Thüring boards were all tin-lead alloy coated. 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