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: Aircraft Security


This chapter will discuss the development of the aircraft's flight deck separation between the pilots, the cabin crews and the passengers, and the implications of the physical barriers. The development of aircraft is considered with the introduction of flight deck doors being an improvement from a curtain. Even though the doors were unlocked and freely accessible to all occupants, the presence of the door encouraged a division of attitudes. Forward of the door were the pilots who flew the plane and made the critical decisions; aft of the door was the cabin crews who looked after the passengers and received orders from the pilots. This thinking is partly due to regulations that have stemmed from the nautical industry, which aviation has developed from in a legal transport context. Like ships, the Captain is fully in-charge of the aircraft, the crews and the passengers.

A number of accidents/events occurred in the 1980s and 1990s relating to the crews (pilot, cabin crew) not communicating effectively, which was partly attributed to the flight deck door being kept closed. Post the 9/11 terrorist attacks on US soil, the flight deck door became a reinforced structural item, being bullet-resistant and locked to keep out would-be aggressors. Additionally, the use of Sky Marshals on flights worldwide became more pronounced in order to covertly manage cabin security and prevent terrorists gaining access to the cabin. Lastly, hydrogen peroxide-based explosives have been extensively used in ground-based terrorist attacks from 2005 onwards, with potential attacks on passenger aircraft in summer 2006 being foiled by UK Security Services. Immediate restrictions on hand luggage liquids were instigated worldwide as an effective counter to this new method of downing commercial aircraft by suicide bombers.

Flight Decks with Curtains and Doors

The mass of the aircraft is a significant factor in aviation, due to the physical performance, including the lift generated. The engines provide the thrust that propels the aircraft forward, which in turn causes the air forward of the aircraft to flow over the wings, and the wings deflect the air flow around them, thus creating lift.

The weight, or more correctly, the mass of the aircraft must be overcome by the lift generated by wings, so if the aircraft is unable to reach sufficient forward speed to create sufficient lift, the plane does not take off. It is this mass-limiting balance that aircraft designers have addressed, even from the earlier days of flight. Early powered aircraft used technologies developed in fabric-covered ultra-lightweight rowing boats, coupled with a motorcycle engine, to allow for powered flight. Typically, the militarisation of new aircraft technology has allowed these small aircraft to develop further, to fly faster, higher and to carry more mass (e.g. fuel, bombs, passengers, etc.). All of the aforementioned mass limitations have been addressed effectively since the end of the First World War, and the ongoing development of high bypass turbine engines has resulted in much greater engine performances.

These early pre-war aircraft had no physical separation between the flight deck and the passenger cabin, partly due to mass limitations, because additional interior structures reduce the carried mass of the aircraft. When a partition was introduced between the flight deck and the cabins, the 'lightweight' solution was a curtain, yet this did not provide the necessary levels of privacy and noise isolation for the flight deck occupants. The advancement of plastics, resins and composite structures in the late 1950s and early 60s allowed for a newer lightweight aircraft interior to be used extensively throughout the interior fittings. With the dedicated privacy of the flight deck, created from a walled partition, the physical presence has also created changes in behaviours.

As discussed in Chapter 6, the culture of us and them between the pilots and cabin crews has been a detrimental factor for many years. The physical presence of the separating bulkhead and door has played an active part in many events, in particular the British Midland Flight 92 accident on 8 January 1989. The B737-400 was being flown from Heathrow to Belfast Airport (Northern Ireland). In-flight, the flight crew misdiagnosed engine vibrations as a pending failure of the starboard (right side) engine. The pilots turned off the starboard engine and the aircraft attempted to land at the maintenance base at East Midlands airport. Prior to landing, the flight crew made a public address to the passengers and cabin crew that the reason for the diversion was because of problems with the engine on the right. The passengers on the left side of the aircraft could see burning debris being ejected from the exhaust of the so called 'good' left engine. No one from the passenger cabin (be it cabin crews or passengers) challenged the pilots' PA. No one brought the error to the attention of the pilots that the passengers and cabin crews could see that the left engine was the defective engine. On approach to East Midlands Airport, the left engine began to deteriorate further and the engine began to fail, reducing the thrust output. The pilots were unable to restart the right engine in time, and the aircraft stalled short of the runway, crashing into the embankment of the Ml motorway just south of junction 24. There were 47 fatalities in this crash, 74 serious injuries out of the 126 passengers and crew on board. The absence of a post-crash fire enabled the injured passengers and crews to be removed from the aircraft without further injury. After the publication of the UK Air Accident Investigation Branch report, the facts were established and the aviation industry tried to learn lessons from this event. They did this by educating pilots and cabin crews of the need to actively listen to PAs, and if a mistake is made, such as in the case of the British Midland accident, for the crews to feel comfortable to openly share those views by communicating with the Flight Deck. UK airlines used this event as a case study for their crews to discuss, highlighting the importance for a cabin crew member to feel empowered enough to enter the Flight Deck and convey their concerns. Likewise, some airlines encouraged their pilots to consider leaving the Flight Deck door open, to bridge this us and them culture, and to remedy the communication difficulties that have occurred over the years.

British Airways 2069, 29th December 2000

This British Airways flight was departing London Gatwick airport, bound for Jomo Keyatta Airport in Nairobi, Kenya. The aircraft in question (see Figure 7.1), a B747-400 aircraft, was fully loaded with 379 passengers and 19 crews, jetting off to Kenya to see in the New Year.

British Airways had worked hard over the years on crew resource management, more so since the British Midland crash, to encourage good open communications between the pilots and the cabin crew. On this flight, like so many other flights, the crews worked well together with the cabin crew visiting the flight deck regularly, and the flight deck door was opened/closed without any fuss in this normal working environment. Later in the flight's cruise all was normal, so the Captain left the flight deck to take a rest, leaving the two other first officers at the controls. At around 5 am local time flying at 35,000ft, a mentally unstable Kenyan passenger, Paul Mukonyi, ran through the upper deck cabin, into the flight deck and attacked one of the first officers. In a very violent struggle between Mukonyi and the pilot, the autopilot was


British Airways 2069 aircraft involved in the cabin incident (passenger attempted homicide/ suicide). (Paul Link.)


BA 2069 Flight track indicating the position of aircraft during the storming of flight deck by perpetrator. (Google Maps.)

accidently disengaged and the plane rapidly descended, with a maximum decent rate of 30,000 ft per minute. The passengers, Captain and crews managed to subdue the assailant, and the aircraft continued on to its destination. The approximate location of the aircraft on the planned flight track during the event is shown in Figure 7.2. In the subsequent investigation, a number of reports after this event suggested that Mukonyi wished to take the aircraft by force, or commit a multiple homicide/suicide event. Although the aircraft later landed safely in Nairobi as scheduled, a small number of passengers required additional medical treatments due to the violent manoeuvres that the aircraft performed. The reporting of this event was very high profile at the time, as the passengers included Bryan Ferry, the musician and his family, the Goldsmith family and Jemima Khan (nee Goldsmith) who married the ex-Pakistan international Cricketer Imran Khan, currently the Prime Minister of Pakistan at the time of writing. The shocking event was captured on a passenger's video camera as Mukonyi was dragged from the flight deck by passengers and crew.

Unfortunately for British Airways, this was not the sole incident where a passenger had tried to storm the flight deck. Two years earlier on 13 February 1998, the Stone Roses lead singer, Ian Brown, was flying on BA 1611 from Paris to Manchester. In-flight there was a significant event where Brown threatened to chop off the flight attendants' hands. Later Brown attempted to storm into the flight deck during the final descent phase of the flight. Brown was arrested on arrival, prosecuted and was sentenced to a custodial detention of four months in a UK prison.

These events have highlighted the ease at which an individual could gain access to the aircraft flight deck, compromising the safety of the crews and the aircraft. The physical barriers were kept to an absolute minimum between the passenger cabin and the flight deck, yet this breech of security, even with the extensive media attention, did not change the working practices at the time.

Aviation security is a concept and skill that has been taught to all pilots and cabin crews for many years. The syllabus includes events that rarely take place, such as hijackings. More frequent events are roleplayed, including the safe management of intoxicated passengers and restraint techniques approved by the carrier, including the use of the handcuffs and restrains that are carried on all aircraft. In-flight security events (including the restraint/ cuffing of passengers) have been a common occurrence for many years, partly attributed to the availability of alcohol onboard the aircraft.

One such event was experienced by an Asian carrier in the late 1990s, where a passenger on an ultra-long haul flight from Asia Pacific to Europe became aggressive and abusive to the cabin crews and passengers. The cabin attendants tried to manage the problem, but this had little effect on the drunk individual. The Captain decided to leave the flight deck and tell the passenger of the consequences of their actions. Being an ultra-long haul flight, the aircraft had a complement of 4 pilots. The Captain's strong words of advice were ignored, so assistance was sought from strong, able-bodied passengers: a number of professional international rugby players assisted the crews in physically subduing the intoxicated passenger, while the cabin crew cuffed him (with his hands in front of his torso).

The verbal abuse and disruptive behaviour continued in the passenger cabin, even though the passenger was seated and cuffed. Passengers nearby were distressed, so the cabin crew decided to move the passenger from the cabin to the toilet (with the passenger still cuffed), and to lock him in the toilet to prevent him from further interacting with the other passengers. While the decision to lock him in the toilet might seem like a reasonable solution, the reality was somewhere different. While in the locked toilet, the cuffed passenger decided to burn toilet papers and paper hand towels with a cigarette lighter that was concealed on his person. Fortunately, all aircraft toilets were fitted with a smoke detector that alerts crews throughout the aircraft if smoke and fire was detected.

The toilet door was removed, the cuffed occupant forcibly removed and the fire extinguished. The perpetrator was later arrested by the police upon landing and prosecuted for endangering the aircraft, the crews and the passengers, resulting in a lengthy custodial sentence.

The importance of this smoke detector is highlighted in a previous accident with Air Canada on 2 June 1983, where a toilet fire in-flight caused the Air Canada aircraft to land at Cincinnati Airport, with 23 fatalities. The danger of in-flight fire is a significant worry to any pilot, as the risk of the flash over phenomena could result in a non-survivable cabin environment. It would be almost impossible to extinguish a fire with the apparatus in the aircraft if this point has been reached. Flash over is achieved when the temperature of the fire raises the surround materials to a level that exceeds the flash point temperature, meaning that all nearby materials spontaneously combust without the need for a flame: everything flammable bursts into flames at this stage, including the cabin occupants.

These events provide a worthwhile lesson to all airlines and crews trying to manage a confrontational cabin passenger, which is not to use the toilets as a makeshift detention cell, as the risk of arson can lead to a more catastrophic event.

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