Despite what seems like a glut of high-profile aviation accidents recently, mid-flight remains the safest part of any aircraft’s journey. It is the runway that represents the biggest threat to safety, in terms of incursions and excursions. In the US alone last year, there were 793 runway incursions across the country, of which 160 were due to operational error, 487 to pilot deviation, and 146 to vehicle or pedestrian deviation.

With such seemingly fraught surroundings, the International Civil Aviation Organization (ICAO) is working hard with its international partners to bring these numbers down. Mark Brierley finds out what the organisation is doing to stem the tide.

Why are the numbers in runway safety stubbornly lower than in other areas of the industry?

Runway-related incidents and accidents emerge from a particularly complex set of operational and human factors. Efforts by individual stakeholders in the air transport sector to address the underlying causes weren’t delivering the intended results, so we came together to format a multidisciplinary, collaborative approach that has been seeing much greater success.

ICAO presently has 12 dedicated runway safety partners that have been sharing information and developing collaborative responses to these challenges. While this remains, as you point out, a "stubborn" or challenging area for aviation safety experts, you should also note that in 2012-13, our collaborative work led to a 32% reduction in runway-safety-related accidents. More importantly than this, however, is that runway-related fatalities have decreased from 179 in 2010 to just one in 2014.

So while this may be a stubborn area of air transport safety concern compared with a sector that is otherwise quite remarkably safe, from a more common-sense standpoint, it is also one where we are now seeing some excellent recent improvements.

What role does aerodrome design play in improving runway safety? Does this extend safety beyond the runway to aprons and taxiways?

Aerodrome design has an impact on runway safety in two main areas: runway incursions and runway excursions. In terms of runway incursions, complex or inadequate aerodrome design significantly increases the probability of an incursion occurring on a runway. The frequency of runway incursions has been shown in many studies to be related to the number of runway crossings and the characteristics of the aerodrome layout. Common factors include:

  • the complexity of the airport layout, including roads and taxiways adjacent to the runway
  • insufficient spacing between parallel runways
  • departure taxiways that fail to intersect active runways at right angles
  • no end-loop perimeter taxiways to avoid runway crossings.

Unfortunately, many aerodrome improvement projects can result in a more complex aerodrome layout that – together with inadequate aerodrome design standards, signs, markings and lighting, not to mention the lack of standard taxi routes – has worsened the situation.

With respect to runway excursions, proper implementation of ICAO standards and recommended practices (SARPs) during the design of an aerodrome is a very important step in helping to avoid or minimise these incidents. Proper geometric design of the runway and associated facilities, according to the physical characteristics as specified in Annex 14, Volume I, provide a solid foundation for preventing and mitigating runway excursions.

Extending beyond the runway, ICAO is also coming out with taxiway design guidance for minimising the potential for runway incursions. Good taxiway design practices should be part of any comprehensive runway incursion prevention programme, with the prime considerations being to limit the number of aircraft or vehicles entering or crossing a runway, provide pilots with enhanced unobstructed views of the entire runway and correct taxiways identified as hotspots.

Beyond the layout, what other considerations are made with respect to aerodrome design?

The design and provision of runway-associated facilities, such as the runway end safety areas (RESAs), are extremely important in mitigating the consequences of a runway excursion. Recent research programmes and evaluations of actual aircraft overruns into arresting systems have demonstrated predictable and effective safety benefits. Recognising the value of these measures, Annex 14, Volume I has been amended to have arresting systems introduced and to strengthen the requirements for RESAs.

To assist pilots and other aerodrome users in approaching, landing and operating on the airport surface, visual aids and cues such as charts, signs, markings and lighting are all important components of effective aerodrome infrastructure. As well as the existing ICAO provisions addressing the integrated use of visual aids to help prevent runway incursions, recent amendments to Annex 14, Volume I, introduced new provisions for enhanced taxiway centre-line markings and mandatory instruction signs to further strengthen runway incursion prevention through visual aid measures.

Runway surface conditions, including runway surface friction characteristics, are similarly vital to the prevention of runway excursion. New and amended provisions concerning runway friction measurement, and surface condition assessment and reporting have also been incorporated in Annex 14, Volume I. ICAO is developing provisions for a global reporting format, including a common taxonomy for runway surface conditions and their correlation to aircraft braking performance, in order to help prevent excursions on contaminated runways.

A comprehensive proposal containing amendments in the areas of aerodromes, meteorology, flight operations, airworthiness, aeronautical information services and ATC has recently been approved by the ICAO Air Navigation Commission, and will be issued to states and international organisations for consultation prior to being submitted for final adoption by the ICAO Council.

What role does ICAO play in setting the standard for safe aerodrome design and how is it disseminated among the aviation community?

ICAO works with the Chicago Convention’s 191 member states, in addition to global aviation organisations, to develop international SARPs that states reference when developing their legally enforceable national civil aviation regulations. There are currently more than 12,000 SARPs reflected in the 19 annexes to the Chicago Convention, which ICAO oversees, and it is through these provisions – as well as ICAO’s complementary policy, auditing and capacity-building efforts – that today’s global air transport network is able to operate more than 100,000 daily flights safely, efficiently and securely in every region of the world.

How do you effectively marshal the efforts of many worldwide offices to successfully work together and reach a consensus on runway safety?

Intensive international cooperation and coordination have been the hallmarks of the global air transport network ever since the first states came together to draft the Chicago Convention. Essentially, this agreement permits the sharing of every signatory nation’s airspace so that a truly global system can be permitted to function.

In the years since it was drafted, virtually every major development or standard relating to international civil aviation has been agreed through ICAO on a consensus basis – a consensus that includes state and industry players.

Is ICAO’s guidance in this area updated proactively or reactively? How are safety issues identified and rectified?

ICAO is becoming less reactive and more predictive or proactive in its approaches to all aviation safety concerns. This process is consistent with the Safety Management System principles that have been being established across our sector for many years now, and has also been enhanced by the wider availability and sharing of data, which permits more effective analyses.

Accident investigations and other reactive safety approaches still play a critical role, however, in bringing to light important safety findings and recommendations. What is most important is that all relevant information and data gets included in the determinations leading to new or amended safety approaches.

What work are you currently undertaking in this field and when can we expect it to be published?

A number of pending Annex 14 developments were outlined earlier. Beyond this, ICAO is actively engaged with IATA and other Runway Safety Programme (RSP) partners to agree on common language and taxonomy, and establish globally recognised key performance indicators for runway safety.

In 2014, ICAO released the first edition of the Runway Safety I-Kit, which included the new ICAO Runway Safety Handbook and many other references produced by the RSP partners to serve as a single reference for runway safety, and promoting the sharing and exchange of safety information, guidance and tools between stakeholders.

A Runway Safety Go-Team methodology was also developed to harmonise and align the multidisciplinary efforts from all partners and stakeholders in providing on-site assistance to airports on establishing and managing runway safety teams.