Pan Am Flight 103 bombing investigation
The investigation into the bombing of Pan Am Flight 103 began after Pan Am Flight 103, en route from Frankfurt to Detroit with stopovers in London and New York City, was blown up at 19:03 on 21 December 1988 over Lockerbie in Dumfries and Galloway, Scotland. The perpetrators had intended the plane to crash into the sea, destroying any traceable evidence, but the late departure time of the aircraft meant that its explosion over land left a veritable trail of evidence. The investigation led to the prosecution, conviction, and imprisonment of Abdelbaset al-Megrahi.
Investigators
In Scotland, responsibility for the investigation of sudden deaths rests with the local Procurator Fiscal, who attends the scene and may direct the police in the conduct of their inquiries. The Procurator Fiscal holds a commission from the Lord Advocate, who is Scotland's chief law officer. Responsibility for the Lockerbie investigation thus rested with Jimmy McDougall, the Procurator Fiscal in the nearby burgh of Dumfries, and with the Dumfries and Galloway Constabulary, by number of officers the smallest police force in the UK. According to a paper presented by the then Lord Advocate Colin Boyd, to a conference of law officers in 2001, the ordinary resources available to them were inadequate to deal with such an investigation.The police effort was therefore augmented by officers from all over Scotland and the north of England, and the Procurator Fiscal was given support from the Crown Office and Procurator Fiscal Service in Edinburgh. Funding the investigation quickly became a political issue and Margaret Thatcher announced that central government, not the Scottish Office, would meet any additional costs involved.
On 27 December 2018, Wired, an online news website, published a long article; it highlights that the head of the U.S. Justice Department’s criminal division, Robert Mueller, oversaw the case. Additional details are given.
Search for clues
On 28 December 1988, just a week after the crash, the Air Accidents Investigation Branch announced that they had found traces of high explosives and that there was evidence that Pan Am 103 had been brought down by an improvised explosive device. Over a thousand police officers and soldiers carried out fingertip searches of the crash site that lasted for months, retrieving 4 million pieces from the fields and forests of southern Scotland. The searchers were divided into groups of eight or ten, with the instruction: "If it isn't growing and it isn't a rock, pick it up." They were asked to look out particularly for items which might be charred and which might therefore have been close to an explosion.British military helicopters flew over the crash site, pointing out large pieces of wreckage to the search parties. Private helicopters, equipped with thermographic cameras, were drafted in to survey the heavily wooded areas surrounding Lockerbie. Within hours of the crash, photographs of the area taken by a French satellite were delivered to the investigators. High-resolution photographs from spy satellites were also provided by the United States Department of Defense and National Aeronautics and Space Administration. Every item picked up was tagged, placed in a clear plastic bag, labelled and taken to the gymnasium of a local school, where everything was X-rayed and checked for explosive residue with a gas chromatograph, after which the information was entered into the Home Office Large Major Enquiry System.
Reconstruction of the aircraft and luggage containers
All parts of the recovered aircraft were taken initially to a hangar at Longtown, Cumbria, where they were examined by investigators from Britain's AAIB; they were then moved to the AAIB's headquarters at Farnborough Airfield in Hampshire for the fuselage of the Boeing 747 to be partially reconstructed. Investigators found an area on the left side of the lower fuselage in the forward cargo hold, directly under the aircraft's navigation and communications systems, where a small section of about square had been completely shattered, with signs of pitting and sooting. The fuselage skin had been bent and torn back in a so-called starburst pattern—petalled outwards—a pattern that was evidence of an explosion.The forward cargo hold had been loaded with capacity baggage containers, made either of fiberglass or aluminium, and filled with suitcases. After the explosion, most of these containers showed damage consistent with a fall from, but two of them—metal container AVE4041 and fibre container AVN7511—showed unusual damage. From the loading plan, investigators saw that AVE4041 had been situated inboard of, and slightly above, the starburst-patterned hole in the fuselage, with AVN7511 right next to it.
The reconstruction of container AVE4041 showed blackening, pitting, and severe damage to the floor panel and other areas, indicating that what the investigators called a "high-energy event" had taken place inside it. Though the floor of the container was damaged, there was no blackening or pitting of it. From this, and the distribution of sooting and pitting elsewhere, investigators calculated that the suitcase containing the bomb had not rested on the floor, but had probably been on top of another case, though there was no proof that the explosion had occurred in a suitcase.
Using the damage to adjacent container AVN7511 to guide them, the investigators concluded that the explosion had occurred about 13 inches from the floor of AVE4041 and about 25 inches from the skin of the fuselage. Federal Aviation Administration investigators then conducted a series of tests in the United States, at which Alan Feraday of Britain's Defence Evaluation and Research Agency is understood to have been present. The tests involved using metal containers loaded with luggage, and detonating plastic explosive within Toshiba radio cassette players in garment-filled suitcases, so as to replicate the sooting and pitting pattern of AVE4041. The tests were said to have proved AAIB investigators' theory concerning both the position of the bomb and the quantity of explosive involved.
The results of these tests were used as evidence at the eventual trial to determine the origin of the bomb suitcase. John Bedford, one of Pan Am's loader-drivers at Heathrow, was able to give evidence about the precise location within PA103 of the baggage container, as well as the location of suitcases inside it, all of which helped investigators piece together how the bomb suitcase came to be there. Bedford particularly remembered handling container AVE4041, he told investigators, because he was born in 1940, and his wife in 1941.
Samsonite suitcase, bomb, clothes, and instruction manual
An analysis by the Federal Bureau of Investigation and DERA forensic teams of the fine carbon deposits on AVE4041 and AVN7511 indicated that a chemical explosion had occurred; that a to charge of plastic explosive had been used; and that the device had exploded 8 inches from the left side of the container.DERA's Feraday and Dr. Thomas Hayes examined two strips of metal from AVE 4041, and found traces of pentaerythritol tetranitrate and cyclotrimethylene trinitramine, components of Semtex-H, a high-performance plastic explosive manufactured in Pardubice, Czechoslovakia. In March 1990, Czechoslovak President Václav Havel disclosed that the former communist regime had supplied a large consignment of Semtex through a company called Omnipol to the government of Libya.
During the fingertip searches around Lockerbie, 56 fragments of a suitcase were found that showed extensive, close-range blast damage. With the help of luggage manufacturers, it was determined that the fragments had been part of a brown, hardshell, Samsonite suitcase of the Silhouette 4000 range. A further 24 items of luggage, including clothing, were determined by DERA to have been within a very close range of the suitcase when it exploded, and probably inside it.
The blast fragments included parts of a radio cassette player and a small piece of circuit board. This rang alarm bells within the intelligence communities in Britain, the U.S., and West Germany, as the West German police had recovered a Semtex bomb hidden inside a Toshiba radio cassette player in an apartment in Neuss, West Germany, in October 1988, two months before PA 103 exploded. The bomb, one of five, had been in the possession of members of the Damascus–based Popular Front for the Liberation of Palestine - General Command, led by Ahmed Jibril, a former Syrian army captain. Feraday travelled to West Germany to examine this bomb, and though he found that the Lockerbie fragments did not precisely match the Toshiba model, they were similar enough for him to contact Toshiba. With the company's help, DERA discovered there were seven models in which the printed circuit board bore exactly the same details as the Lockerbie fragments.
Further examination of the clothing believed to have been in the bomb suitcase found fragments of paper embedded into two Slalom-brand men's shirts, a blue baby's jumpsuit of the Babygro Primark brand, and a pair of tartan trousers. Fragments of plastic consistent with the material used on a Bombeat and pieces of loudspeaker mesh, were found embedded in other clothing which appeared to have been inside the bomb suitcase: a white, Abanderado-brand T-shirt; cream-coloured pyjamas; a fragment of a knitted, brown, woollen cardigan with the label "Puccini design"; a herringbone jacket; and brown herringbone material, some of which bore a label indicating it came from a pair of size-34 Yorkie-brand men's trousers.
Contained within this herringbone material were five clumps of blue and white fibres consistent with the blue Babygro material. Trapped between two pieces of Babygro fibres were the remains of a label with the words "Made in Malta". This label was the first indication of possible Libyan involvement.
DERA also found the fragments of a black nylon umbrella that showed signs of blast damage. Stuck to the canopy material were blue and white fibres, consistent with the fragments of the Babygro. Investigators were left in no doubt that these items had been wrapped around the bomb inside the Samsonite suitcase. If they could find the person who had bought the clothes, they believed, they would find the Lockerbie bomber.
The instruction manual for the Toshiba cassette player was found in a field 70 miles from Lockerbie by Gwendoline Horton the day after the crash. Later, during the trial, Mrs Horton could not positively identify the official exhibit as the same piece of paper she had found, claiming later that the paper she had found had been more or less intact and not in several pieces. Police at the trial said that the paper had been damaged following a series of forensic tests. Robert Ingram, a civilian search and rescue worker told the court that police had visited him some months after the crash to ask him to confirm finding items that he did not, in fact, recall recovering.