Plenty of people already know that driving to the airport is statistically more dangerous than taking a trip on a commercial aeroplane. What most people don’t realize is just how much safer flying has become in all the decades since that fact became true.
A 2020 MIT study found that the death rate for commercial flights is now at 1 per 7.9 million passenger boardings, compared to 1 per 2.7 million boardings in 1998–2007 and 1 per 1.3 million boardings back in 1988–1997. Even more remarkably, that safety rate continues to climb year over year, even as the global aviation industry continues to handle more flights than ever before.
A lot of these safety improvements can be attributed to hard-earned lessons learned following previous aviation incidents. Over the years, aviation disasters caused by maintenance issues have led to improvements in the upkeep and repair of aircraft, especially at the component level.
Maintaining aircraft parts is a much more difficult challenge than it may seem on the surface. Modern wide-body aircraft can have several million parts, with the famous Boeing 747 having over six million discrete components. Though not all aircraft are as complex as the 747, ensuring the quality of all aircraft parts remains key to aviation safety.
Over the years, the effective maintenance and replacement of aircraft parts has evolved into a remarkable, multi-faceted discipline. As new materials, structural concepts, and regulatory procedures are introduced, the challenge of keeping these components in good working order has also evolved to keep pace. Here are some of the approaches professional maintenance teams take to ensure the utmost safety of aircraft and passengers:
Holistic Maintenance Programmes
Top-tier maintenance programs go beyond the documentation that manufacturers offer and are partly based on the direct experience of crews. Inexperienced crews can cause issues in flight, so modern maintenance programmes emphasize passing on procedures and experiences to ensure consistency in maintenance practices.
To avoid variations in procedures, quality management systems (QMS) are also implemented to provide a structured framework. On top of this, a culture of safety and continuous improvement is also inculcated in maintenance crews to further push the envelope of aircraft part safety.
Structural Fatigue Management
While some aircraft types can serve for decades, accidental damage, environmental deterioration, and fatigue can all take a toll on aircraft components, particularly the airframe. Fortunately, the early detection and replacement of compromised parts can ensure that most aircraft can continue to operate almost indefinitely.
Some methods employed to detect structural issues include manual inspections and the use of advanced non-destructive evaluation (NDE) technologies like ultrasound testers. As new aircraft designs are employed, maintenance teams also adapt their approaches to better suit new parts and materials.
Component Maintenance and Reliability Centred Maintenance (RCM)
Reliability-Centered Maintenance (RCM) is an approach that identifies maintenance tasks based on the tested reliability characteristics of the components. Component maintenance, on the other hand, focuses on ensuring that hardware items reach their rated use cycles through adequate maintenance. Either or both approaches may be used, depending on the context.
RCM involves hard time removal (pre-emptive replacement of components that hit a set number of cycles) as well as condition-based maintenance and functional checks to prevent in-service failures. Common component maintenance tasks include lubrication, inspections, restorations, and discards based on the degradation characteristics of the components.
Addressing Ramp and Maintenance Damage
Ground handling and servicing activities account for a significant portion of aircraft damage. Adding protocols and improvements in areas prone to damage (such as interfaces with servicing equipment) can mitigate these issues. Additionally, maintenance crews must conduct inspections to identify and rectify such damage promptly.
Environmental Control
Environmental factors such as temperature fluctuations, humidity, and exposure to corrosive elements can negatively impact aircraft components. For that reason, aircraft that are not currently in flight operations must be housed in hangars to mitigate these factors. In addition, maintenance crews must apply appropriate coatings and sealants to exposed aircraft parts and ensure proper drainage in areas where potentially corrosive moisture can accumulate.
Technological Integration for Advanced Inspections
Aircraft maintenance crews now employ a significant amount of technology to ensure the integrity of aircraft parts. Aside from the aforementioned NDE technologies, predictive modeling is also employed to give crews an idea of the potential spread of fatigue damage. Being able to detect invisible signs of stress and develop predictive models for crack growth helps in setting appropriate inspection thresholds and intervals, particularly for aging but still-airworthy aircraft.
Training and Certification of Maintenance Personnel
Regular retraining programmes to keep technicians updated on the latest methodologies and technologies are essential for aircraft part maintenance. Continuous education helps technicians stay proficient in handling new maintenance techniques and aircraft components, ultimately improving their work quality. Certification further ensures that personnel meet the most current industry standards and can transition to different maintenance environments.
Future-Proofing Aircraft Parts Maintenance for Safer Aviation
Maintaining aircraft parts according to modern safety standards requires a comprehensive and ever-evolving approach. The pace of aerospace innovation means that the maintenance programmes we see today are not likely to be sufficient for standards that will be in place a decade or so from now. Knowing this, aircraft fleet owners must prioritise maintenance providers that can keep pace with the aviation industry’s increasingly complex demands.
