Keeping Aircraft Reliability Competitive Through Its Life Cycle

The first entry into service of any new aircraft  typically has a ‘honeymoon’ phase that is a  relatively trouble-free operation. This applies to  both existing and new platforms. However, this  phase typically lasts much longer for an existing  platform’s newly built aircraft. This is where feedback from the  Original Equipment Manufacturer (OEM) and communication  with other airlines with similar fleet types is critical to gain  traction in reliability, maintainability, and overall  cost control as the aircraft gains time in service.  Operational economics will always play a role  in the ultimate life cycle of an aircraft, but  if the aircraft’s reliability is competitive, it  can be an overwhelming factor to keep it  in service. 

An airline’s fleet size and data  quality are certainly integral in the  reception of its reliability input and it  has to be representative of the World  Wide Fleet data by the OEM. Each  operator has unique routes and operating  environments that play a big role in the  long-term understanding of the fleet  reliability data, especially over time in  service. The Approved Reliability Program  based on the Maintenance Review Board  (MRB) of each operator also plays a critical  role in continuous airworthiness and  improvement of the aircraft over its life  cycle. However, the reliability can easily  be enhanced by staying engaged in the  analysis of pilot discrepancies, non-routine  and routine maintenance discrepancies, and  work cards. Understanding these discrepancies  and their causes can yield tremendous insights,  leading to increased reliability. 

Rotable shortages often occur after many years of operation  as the aircraft matures through its life cycle. Teardown reports and  communication with the vendor regarding the faults can result  in an airline maintenance task or improved troubleshooting,  preventing schedule interruptions and extended out-of-service  times. If these types of events are addressed during the entire  aircraft life cycle, it adds to an overall effort to maintain a very  high level of reliability. 

"The Aircraft Will Tell You  What It Needs Throughout  Its Life Cycle, Through  Various Discrepancies.  The Goal Should Not Just  Be How To Correct The  Discrepancy, But Also  How To Prevent It From  Occurring Again" 

Advances in technology to improve reliability can be collected  from other OEM platforms or by attending trade shows. Some  advancements are very difficult and can be expensive to adapt to  aging platforms, while others make sense from a reliability and  cost of ownership perspective. One of the best examples in recent  times is the manufacturing advances in LED lighting. In the past,  it was accepted that bulbs had a known life; if critical they could be  put on a time replacement interval, based on statistical analysis.  On some platforms, inoperative bulbs play a significant  role in dispatch rates (on-time departures), due to  criticality or accessibility, which translates to  an uncontrollable delay in flight departure.  Consequently, the navigation lights were  recognized by many OEMs and they  created a modification to add additional  bulbs to be switched (some automatic and  other manual) as an approved alternate.  These types of modifications are costly  and require significant man-hours and  downtime to install. However, with  advances in direct replacement, LED  lighting technology has dramatically  changed failure rates, and with a relatively  low cost, they have become a way to  improve safety and dispatch reliability. 

Non-critical fatigue of the airframe  and components come into play as the  life cycle continues. A review of the  OEM’s service bulletins can yield much  insight into ways this can be kept in  check. Continuous monitoring of aircraft  for out-of-service discrepancies through  scheduled and unscheduled inspections can  help formulate plans to install preventative  reinforcements, replacements, and alterations  to avoid recurring fatigue-related findings; thereby,  increasing the availability of the aircraft and preventing  disruptions of aircraft in service. 

The aircraft will tell you what it needs throughout its life  cycle, through various discrepancies. The goal should not just be  how to correct the discrepancy, but also how to prevent it from  occurring again. Detailed attention and corrective measures to  what the aircraft requires to operate from the beginning to the  end of the life cycle will yield the highest reliability possible.