Faced with new safety hazards as well as with a variety of potential acts of unlawful interference, the aviation community needs to constantly assess the global exposure to risk when trying to mitigate a specific safety or security risk. The overall risk to aviation safety posed by any new security risk, and vice-versa, need to be systematically addressed and well understood by aviation safety and security regulators at a global level.
This is the case for example for supplemental oxygen supply systems installed in aircraft. These systems need to ensure that passengers are protected in lavatories should a sudden loss of cabin pressure occur, but also limit the exposure to any security threat of hostile acts using chemical oxygen generators. Cockpit door design is another example of safety/ security balance that needed to be found. Following the 11 September 2001 attacks, several measures were introduced to reduce the risk of unwanted persons entering the cockpit. Reinforced cockpit door systems were mandated, and their design was subsequently fine-tuned to address the safety risks in the areas of rapid aircraft depressurization, pilot incapacitation, post-crash cockpit access, and door system failure.
...passenger aircraft cargo compartment fire suppression systems are designed to provide protection from the risk of fires that had been determined to be likely to occur at the time of their design.
A more recent example was the prohibition by a Member State of Portable Electronic Devices (PEDs) larger than a smartphone in the passenger cabin, due to concerns that an improvised explosive device (IED) could be introduced in the PEDs with the intent to detonate that IED in the passenger cabin. This has led to the relocation of those PEDs to the cargo compartment. Since almost all of these devices contain lithium batteries, the risk of cargo hold fires was potentially increased. Security risks, mitigated by this measure, were therefore displaced into safety risks.
The Technical Instructions for the Safe Transport of Dangerous Goods by Air (Doc 9284) recommend that these devices be carried in the cabin on the basis that should a PED initiate a fire, cabin crew can take appropriate fire-fighting action expeditiously and monitor the device for re-ignition. Moreover, passenger aircraft cargo compartment fire suppression systems are designed to provide protection from the risk of fires that had been determined to be likely to occur at the time of their design. Those risks did not include the ones presented by lithium batteries.
The ICAO Council, at the first meeting of its 211th Session, agreed to the establishment of a temporary multidisciplinary Cargo Safety Group (CSG), tasked with evaluating existing aircraft capabilities, identifying the safety hazards posed by the carriage of PEDs in checked baggage and assessing the associated safety risks. Based on studies conducted by the FAA and EASA, the CSG concluded that:
- there would be a potential ten-fold increase in the risk of cargo fires if PEDs were relocated from the cabin to aircraft cargo compartments; and
- combining PEDs with other dangerous goods in a Class C compartment could result in an explosion before halon could be sufficiently discharged; no protection would be provided in a Class D compartment for a similar event.
The CSG found that additional data was needed to more precisely determine the safety risks. ICAO therefore sent a State Letter in January 2018 requesting States to provide pertinent data about:
- the number of aircraft with Class D compartments
- the number of incidents involving PEDs that have occurred or been reported since 2007 an estimation or an average number of PEDs carried per passenger per flight and their location during flights.
ICAO has received responses from States as well as from the International Coordinating Council of Aerospace Industries Associations (ICCAIA). The consolidated results are being analyzed in order to contribute to achieving the optimum mitigation strategies to reduce to an acceptable level both security and safety risks posed by the carriage of PEDs.
States that did not respond to the State Letter 2018/02 are invited to send to ICAO the information from their operators on these topics as soon as possible.
This article was originally written for the ICAO EUR/NAT Office’s Newsletter (Issue 3) on May 2018. A full list of their newsletters can be found here.