BOTH WASHINGTON AND LONDON have now expressed the view that Russian Metrojet Flight 9268 was ‘more than likely’ downed by an explosive device placed on board the aircraft.

Both US and British government agencies are citing intelligence sources that speak of an inside job or terrorist ‘assist’ at Sharm el-Sheik Airport. They claim that Islamic State affiliates on the Sinai Peninsula, either Ansar Bayt al Maqdis or Province of Sinai may have persuaded an employee at Sharm el Sheik to place an explosive device on board the ill-fated flight which was carrying 224 passengers and crew to St Petersburg.

In the aftermath of the incident, the Egyptian authorities have sacked key figures at the airport including its head of security. The Irish Government has followed the example of UK Foreign Secretary by advising Irish air operators not to fly to or from Sharm el-Sheik for the foreseeable future.

The Russians have prior bitter experience of attacks on their passenger aircraft. In August 2004, two commuter flights operating from Domodedovo International Airport, Moscow were destroyed by female Chechen suicide bombers.

The women, Satsita Dzhebirkhanova and Amanta Nagayev boarded the passenger flights – one to Sochi and the other to Volgograd – with plastic explosives concealed on their persons. Like drug mules, the women are believed to have concealed the high explosives internally, in body cavities.

Both aircraft were destroyed at high altitude during the cruising phase of flight. Volga AviaExpress Flight 1353 disappeared from radar screens without warning 26 minutes after take-off and all 43 passengers and crew on board were killed. Siberia Airlines Flight 1047 disappeared shortly after and all 46 on board were killed in an explosion at high altitude.

Wreckage of the Russian plane. Associated Press Associated Press

During the investigation of the crashes, Russian authorities found explosives residue and traces of high explosive RDX on debris from both planes.

Suspicions surrounding Metrojet Airbus A321

Suspicions were aroused when the Russian Metrojet Airbus A321 disappeared from radar screens 23 minutes after take-off on Saturday after it approached its cruising altitude.  The timing of its disappearance is significant for a number of reasons.

Most air crashes occur during the take-off and landing phase of flight. The Airbus A321 is a highly reliable aircraft with an excellent safety record. Accidents involving Airbus aircraft during the cruising phase are rare and normally involve a constellation of negative factors such as bad weather, technical faults and cockpit incidents.

None of these are reported to have occurred on Saturday. No mayday warnings were issued by the cabin crew and no automatically generated fault indicators were sent either. The plane appeared to simply fall from the sky after a fast moving – instantaneous – catastrophic event.

Investigators and intelligence sources will also compare the duration of the doomed flight to that of Pan Am 103 – which was destroyed by an explosive device placed in the luggage hold – over the Scottish village of Lockerbie in December 1988.

Wreckage of the Pan-Am Boeing 747 in a Scottish field at Lockerbie in 1988. PA PA

Sequence of events similar to Lockerbie incident 

Two hundred and seventy passengers and crew – mostly US citizens – were killed in that incident including 11 people on the ground. The sequence of events and the distribution of debris – including range and lateral spread of plane fragments and bodies – in the case of Metrojet Flight 9268 are broadly similar to that of the Lockerbie incident.

The timing, sequence of events and sudden loss of structural integrity also mirror the destruction of Russian Volga AviaExpress Flight 1353 in 2004.

For now, the crash investigators will be mapping and tracking debris from the wreckage in order to establish the central focus of the plane’s disintegration. They will be looking for evidence of external impact or internal detonation along with evidence of stress fractures or tell-tale signs of weaknesses in the mainframe of the aircraft.

They will pay particular attention to any of the signature signs of a high explosive device including metal curled outwards or blast and burn patterns along with the shrapnel effects consistent such an improvised device.

Post mortem examinations of victims of the crash – particularly, where possible, of passengers located close to the centre of gravity of the detonation would reveal the high temperature burn effects and pulping of internal organs along with the shattering of bones that are consistent with the impact of high explosives on soft tissue.

Poor record of disclosure

It is not clear how communicative Egyptian and Russian investigators will be with regard to such findings. They Egyptians have a poor record in disclosing the findings of previous air incidents.

In October 1999 an Egyptian Boeing 767 passenger jet – EgyptAir Flight 990 – was deliberately crashed into the Atlantic Ocean just south of Nantucket en route from New York to Cairo International Airport.

All 217 passengers and crew on board were killed in that incident by the pilot in an act of suicide similar to that perpetrated by GermanWings Flight 9525 first officer, Andreas Lubitz in March of this year.

In the subsequent US examination of the incident involving EgyptAir, the Egyptian authorities were uncooperative and reluctant to release the findings of the air accident investigation report. With so much at stake for Egypt’s international prestige, stability and tourism revenues, it will be interesting to see how transparent and timely the current investigation will be.

Investigators at the scene of the crash. Associated Press Associated Press

The Russian authorities will certainly be anxious to find out precisely what happened to its citizens over the Sinai Peninsula. Particularly so given President Putin’s recent offensive against Islamic State in Syria. If Islamic State’s claims prove to be correct – in regard to destroying the Russian aircraft – it will be the most significant attack on civil aviation by militant Islamists since 9/11.

Whatever the outcome of the investigation into the loss of Metrojet Flight 9268 – tensions will be running high among militant groups and state actors with access to North African and Middle Eastern air space and facilities.

This set of factors – including the fate of Malaysian Airlines Flight MH17, destroyed by a Russian BUK missile over Ukraine – ought to inform the operations of all major airlines and charter flights in the region. Until the facts are clarified – if they ever are – caution should be the order of the day.

Dr Tom Clonan is a former Captain in the Irish armed forces. He is a security analyst and academic, lecturing in the School of Media in DIT. He is also an Independent candidate for Senate-TCD Panel. You can follow him on Twitter here.

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