Recent news of two Airbus 320neo aircraft incidents involving IndiGo and GoAir has led to a great deal of discussion. This, at a time when rival aircraft Boeing 737 Max remains grounded with an ongoing congressional investigation in the US. Questions and speculation have arisen about flight safety. This article highlights the A320neo aircraft and the engine that powers it.

The A320neo was developed as a result of rivalry between Boeing and Airbus. Both manufacturers were keen to produce an aircraft that airlines would order in significant volumes. For this, fuel efficiency was the key. And fuel efficiency largely depends on engines. Thus the name NEO: New Engine Option. In India, its first customer was IndiGo, which placed an order of 150 units. GoAir soon followed with a 72-aircraft order. The first A320neo took to Indian skies in March 2016.

Customers of the aircraft can select engines from two manufacturers: CFM International, and Pratt and Whitney (P&W). While CFM adapted its existing and extremely successful engine (CFM56) via modifications, P&W built a new engine from the ground up—the first such effort in the last three decades. Both were aiming for a quieter, more powerful and more fuel-efficient engine. Both Indian launch customers chose the P&W engines.

But the engine introduction brought with it a host of challenges.

After the A320neo began operating here in 2016, initial issues emerged. These were with the P&W engines and those related to start times, spurious cockpit warning messages and hydraulic fluid temperatures. They resulted in delays of aircraft delivery. The issues were addressed via hardware and software upgrades. But soon, more issues emerged, including those involving fan blades, combustor chamber issues (necessitating replacement of components) and component failures. These, too, were addressed collaboratively between the engine manufacturer, the airlines and Airbus through the end of 2017.

Until 2017, airlines were cognisant of the fact that new engines have teething issues, and that these were being addressed. But the challenges continued.

The year 2018 saw the emergence of additional issues. The most significant of these led to an emergency airworthiness directive. The problem was traced to a part called the knife-edge seal.

This year has seen further challenges. Problems have been traced to its third-stage low pressure turbine, and its main gear box; vibrations have been reported as well.

While each issue, as it emerges, is being collaboratively addressed, several others have cropped up. These often require grounding of aircraft, delays in delivery schedules and operational changes.

As the problems continue, these have frustrated the regulator, the public and the airlines themselves.

The regulator in charge of Indian skies is the Directorate General of Civil Aviation (DGCA). For the most part, it follows the the Federal Aviation Administration (FAA) of the US, and the European Aviation Safety Agency (EASA). This is in line with global norms. Yet, given the concentration of the A320neos powered by P&W in the Indian skies, industry experts say the regulator in this case needs to take a more proactive stance.

Looking back, one can see a pattern of patchy and reactive actions by India’s regulator. In 2017, the regulator mandated increased engine inspections. This started with a requirement to conduct examinations of the engine at 1,500 flight hours, which was later reduced. For warning messages traced to a specific component, initially the DGCA had allowed an extra 10 hours of flight time to recover the aircraft. This, too, was later revoked.

In 2019, when EASA issued an emergency airworthiness directive (EAD) for the A320neos powered by P&W engines, the DGCA followed suit. Experts say DGCA should have led this charge.

Recently, the DGCA directed both IndiGo and GoAir to replace unmodified engines, giving the airlines 15 days for it. This was then extended. Later, a new directive was issued instructing IndiGo to ground all A320neo family aircraft with unmodified P&W engines for every new A320neo plane added. The deadline this time was 31 January 2020.

The assignment of dates, extensions and waivers have led many to question the logic behind the DGCA’s timelines and the impact on flight safety. Aviation, after all, is a very exacting industry and the primary fiduciary duty of all stakeholders is passenger safety.

The regulator’s challenges are also compounded by the fact that the regulatory risk assessments are not shared publicly, apart from lack of digitization and a talent crunch, since it is staffed with generalists rather than aviation specialists. Add to that the viral spread of information via social media. As such, speculation abounds. And questions remain.

To be clear, one has to delink the aircraft and the engine. The majority of the DGCA’s directives are related to the P&W engines and not to the aircraft itself. For A320neos powered by P&W engines that entered commercial service in 2016, these P&W engines now have a record of over 4 million flight hours of passenger service and an in-flight shutdown rate of 0.01 per 1,000 engine flight hours—well within global norms.

But the ongoing engine issues have several speculating whether they are linked to design, operating environments, operational parameters or other factors. Items such as pending certification to fly longer distances over water and a possible delay in deliveries of newer aircraft are also adding to the speculation.

With 182 A320neos currently in the Indian skies and 75% of them powered by P&W engines, everyone has a common question. By when does P&W expect its engines, and by extension the A320neo, to be completely incident-free?

Satyendra Pandey was head of strategy for GoAir and also led the advisory and research teams at the Centre for Aviation (Capa)

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