Sunday, June 23, 2024

Rough Waters Ahead: Troubles With The PW1100G

By Bikram Vohra

Even as power plant manufacturers put their best foot forward and attempt to invent sustainable alternatives to fossil fuels, the fallout from the Pratt & Whitney crisis with the Geared Turbofan has generated a fair amount of consternation in the industry. On 26 July this year, it announced the recall of around 1,200 of the company’s 3,000 Geared Turbofan (GTF) engines. 

It saw a need for further inspection of microscopic cracks in a specific batch of high-pressure turbine disks. These engines would be recalled before their standard maintenance schedule, thereby grounding parts of the fleet and playing havoc with flight plans for several airlines.

What makes it so dire is that since its inception in 2016, it has been a successful option for narrowbodies, especially the A320neo. This issue directly hit 57 airlines, according to published reports. It also compounds the negative fallout of crippled supply chains, and in India, we have seen Go First fly deep into the red and declare voluntary bankruptcy because of delays in engine spares by the same company.

The parent company Raytheon has been quick to promise not only compensation but also reassure carriers that there is no compromise in safety, and unlike the issues with the 737 Max or even the smoke in the batteries of the 787 Dreamliner, the planes were not compromised. 

But that comfort does not mitigate the immediate hassle of making planes inactive. Airlines must remove hundreds of Pratt & Whitney PW1100G geared turbofan (GTF) engines from the wings of Airbus A320neo-family jets by the end of 2024 to inspect for defective high-pressure turbine and compressor discs.

With over 10% of aircraft with GTF-powered engines currently parked, more are likely to follow. A quarter of these belong to Go First. The Raytheon assurance aside, there is always a potential threat when a flaw is found. 

The ‘what if’ factor cannot be ignored. After all, Boeing did not ever think that Lion Air and Ethiopian 737 Max aircraft would suffer crashes because of the difference in the angle of attack sensors. The MCAS system took that erroneous information and activated – repeatedly pushing the plane’s nose down during the time it was in the air after take-off.

Go First has replaced 510 Pratt & Whitney PW1100G geared turbofans (GTFs) in recent years, and in its legal filings, reported it suffered because it was managing sixty-four of what it calls “defective” PW1100Gs, citing combustor and other issues. In a scary submission, it is reported lawyers for the carrier have said, “GTF engines suffer from a set of serious design and/or manufacturing flaws and have not remotely performed as Pratt & Whitney (or Go First) expected.”

A few weeks back, Indigo had to temporarily mothball fifty aircraft courtesy of the microscopic contamination in the engines and the recall from Pratt & Whitney. As many as 136 A320s of 313 strong fleet use these engines. Vistara (India): Vistara, a joint venture of Tata Sons and Singapore Airlines, had to deal with engine-related challenges on their A320neo fleet, affecting their operations and necessitating additional maintenance and inspections. 

The same was reported by Air India on its 320neo fleet. It must hurt P &W that Air India has confirmed its order for 800 CFM International Leap-series engines to power its fleet of 210 Airbus A320neo/A321neos and 190 Boeing 737 MAX family aircraft. Soon after the Paris Airshow, the carrier gave CFM the nod.

Another carrier is Spirit, a Florida-based ultra-low-cost airline now removing planes from summer ops in the middle of the summer rush and hurting enough to worry about consequences since it is the largest operator of 320neos, having as many as seventy-nine planes that might have to be grounded in phases. 

Asia Pacific also reported that making its 33 GTF-powered aircraft non-operational will have more than a ‘significant’ impact on its schedule. Lufthansa has probably grounded ten of its A320s for the same glitches.

Wizz Air has had to drop its traffic uplift by 5% and is smarting. Hawaii has echoed its displeasure and had to block five of its routes and is also supporting Go First’s legal case. And this is where things could get sticky and unpleasant. 

Go First has practically gone on record, implying a conspiracy to destroy it. However dramatic this might sound, it does muddy the waters. It has also taken the step of suing the engine maker for INR80 billion rupees (USD977.2 million) in damages at the Singapore International Arbitration Centre (SIAC). Pratt & Whitney “has repeatedly failed to meet” its assurances related to the engines over the years, an airliner spokesperson said.

A report in Moneycontrol puts a certain perspective on how things will pan out. “Even if the Delaware court rules in favour of Go First, Pratt & Whitney will likely pursue the case in a higher court and may even look at an out-of-court settlement. 

Going by the history of legal disputes between aircraft equipment makers and airlines, disputes may take at least a year to get resolved. However, even if the legal dispute between Go First and Pratt & Whitney is resolved, the United States company still faces global supply chain issues, which will limit the supply of engines to Go First for six months.”

Not just that, but the power plant company is not likely to accept any court decision that underscores its incompetence and, through a major award, leaves egg dripping on the manufacturer’s face.

For Pratt & Whitney, it is a major mountain to navigate largely because there is a growing belief in the industry that the manufacturer dragged its feet over the issues facing the GTF. Seen in light of the fact that the demand for narrow bodies up until 2042 crosses 43,610 aircraft, it would be an acceptable figure to tick 33,000 of these, give or take, as single-aisle aircraft. 

The two engine choices are the Pratt & Whitney 1100 GTF family and the CFM 56, a worthy challenger. Unless Rolls Royce pulls a rabbit out of its hat for this segment, the CFM 56 is going to be hardplaced to swim in this sea of riches.

Ironically, the popularity of the GTF engine type is a paradox because it has had problems in the past. The engine was developed to improve fuel efficiency, reduce emissions, and enhance performance, but technical challenges have raised concerns about its reliability and financial implications for airlines and manufacturers. And yet, in counterpoint, it has saved airlines a bundle of cash in fuel costs. That is why the affection for this technology persists.

The 1100 has had issues in the past. One of the major problems with the PW1100G engine was related to the knife-edge seal in the High-Pressure Compressor (HPC) aft hub. This component experienced premature wear, resulting in unexpected engine shutdowns and airline operational disruptions. “Pratt & Whitney then redesigned the seal and collaborated with airlines to implement fixes. 

Another challenge faced by the PW1100G engine was related to the combustor liners and suspected durability. This led to an increase in engine maintenance and overhaul costs. Additionally, the engine’s geared architecture, although providing fuel efficiency gains, introduced complexities and challenges in its maintenance and repair processes.”

Now, this new issue means every aircraft recalled will be inoperable for 60 days, and that is a big loss for every affected airline. This then becomes a grim exercise that could take till the end of 2026 to complete only if Pratt & Whitney has the capacity to fulfil the requirements through its network of service providers in its global supply chain. 

Bikram Vohra is the Consulting Editor of Indian Aerospace & Defence


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