IndiGo, India’s largest airline, and rival GoAir recently won a reprieve when the Directorate General of Civil Aviation (DGCA) extended a 31 January deadline for modification of P&W engines installed on their A320neo planes to May-end. But a slew of incidents, the latest being the return of an A320neo aircraft on Thursday following a loud noise during a flight from Mumbai to Hyderabad, highlights the risks passengers would have to endure unless the engines are fixed or a blanket ban imposed by the regulator on flying A320neo planes with P&W engines.
Until modifications are made to the faulty P&W engines, IndiGo and GoAir planes have been permitted to fly on the condition that at least one of the two engines on the A320neo aircraft has been modified. But flying an aircraft even with such precautionary steps may not be an adequate protection.
“It is assumed that one engine will have a malfunction, but what if by sheer coincidence the remaining one also develops a fault, the risk is very high,” said Amit Singh, an air operations and safety expert, and a captain at Gulf Air.
“It is a known defect and cannot be treated as a regular fault. When will DGCA say enough is enough based on a scientific evaluation?” said Singh, alleging that the regulator is “commercially driven and (therefore) does not want to ground the aircraft”.
The European Union Aviation Safety Agency (EASA) issued a fresh warning in December about a potential dual-engine failure on the A320neo family of planes fitted with P&W engines. In an airworthiness report issued in December, EASA said low-pressure turbine blades on some P&W engines on A320neo planes had low damage tolerance and could immediately “fracture”, or develop cracks on impact.
“This condition, if not corrected, could lead to dual engine in-flight shutdown, possibly resulting in reduced control of the aeroplane,” the aviation regulator said and asked airlines to replace at least one, if not both P&W engines, by March-end.
To be sure, DGCA told IndiGo in Novemberthat its efforts to modify the glitch-prone older P&W engines on the A320neo planes were not satisfactory. The regulator intervened after a series of technical snags last year involving P&W engine-powered A320neo planes operated by IndiGo. DGCA has threatened to ground all the affected planes if IndiGo and GoAir are not unable to modify the affected P&W engines by the extended 31 May deadline.
IndiGo, which controls around half of the domestic air passenger travel market, will have to complete procurement of as many as 135 engines and replace all its older engines by the deadline, according to plans submitted to DGCA, Airbus and P&W.
Out of IndiGo’s fleet of more than 250 planes, 96 are P&W engine-powered A320neos.
A spokesman for IndiGo did not respond to queries on whether the airline would expedite procurement of P&W engine replacements and consider grounding aircraft with unmodified engines. A spokesperson for P&W India declined to respond to queries.
By January-end, IndiGo is expected to complete the modification of about 70% of the affected engines, a government official said on condition of anonymity. GoAir will need to replace 13 P&W engines.
A senior pilot of an Indian airline, who has flown the A320neo with P&W engines, said the engines are problematic and repairing them is costly as it can’t be addressed with simple fixes such as software upgrades. “It probably needs structural changes, which are not easy,” he said on condition of anonymity. CFM engines on the same aircraft, he added, had proved far more reliable. P&W’s rival, CFM International, a joint venture of General Electric Co. and Safran SA, supplies LEAP-1A engines for A320neos.
In June, IndiGo announced an order for jet engines worth $20 billion from CFM to power its 280 A320neo and A321neo aircraft, following the snags with P&W engines.
Another senior pilot, who declined to be named, said the lack of reliability of P&W engines affects the extended diversion time operations (EDTO) allowed by regulators to airlines, which means that A320neos with P&W engines would have to stick to a flying path that is always in close proximity to other airfields on its flight path.
Passenger planes are generally allowed a maximum leeway of around 200 minutes of flying to the nearest airfield, whereas others with low reliability track record may be required to fly within 60 minutes of the nearest airport. The lower the engine reliability, the longer an aircraft has to travel.
“For example, even within India, a domestic airline may not be able to fly to Port Blair because of the EDTO requirement as there are no airports close by and the aircraft has to fly for a long time over the sea,” the pilot said.
Intense competition has resulted in cut-throat fares, prompting airlines to buy engines that are the most fuel-efficient. Jet fuel accounts for 30%-40% of an airline’s costs.
H.S. Khola, a former director general of civil aviation, said a comprehensive solution is needed as air travel growth within the country has probably outpaced a “maturing of the system”.
“These are issues that may one day create a serious problem, if they are not handled properly. The safety audit has to be of a very high level. These should not be dictated by commercial aspects,” he said.