The Directorate General of Civil Aviation (DGCA) has provided relief to IndiGo and extended the deadline for replacing all snag-prone Pratt and Whitney (PW) engines in the airline’s fleet by four months, though the engine maker recently identified a new problem.
In November 2019, the DGCA instructed IndiGo to replace 120 engines on its PW-powered A320neo planes by the end of January 2020, following four instances of mid-air engine shutdowns in the span of a week. However, on December 16, 2019 PW notified a new cause for glitches in the low-pressure turbine in engines — “fracture of Mid Turbine Frame (MTF) Piston seal” — and advised boroscopic inspection of the engines. Following this, another 15 engines were identified for replacement. The watchdog has now said that the airline can replace all its engines by May 31, 2020.
Holiday delay
In a statement, the DGCA said that IndiGo will be able to replace only 70% of these engines by the January 31 deadline. “The procurement of modified engines was adversely impacted due to holidays during Christmas and New Year at MRO [maintenance, repair and overhaul] facilities,” the DGCA reasoned.
However, IndiGo has already replaced one out of two engines per PW-powered A320neo in its fleet, in accordance with a different advisory issued by the DGCA.
“It is expected that the mitigation measures put in place, such as the introduction of MTF Piston Seal, in addition to the existing Boroscopic Inspections and introduction of Alt Climb procedure, will help in containing the engine failures on wing,” said the DGCA.
The Alt Climb procedure refers to the lower thrust during climb advised by the DGCA after it found in November that the application of higher thrust during take-off by IndiGo pilots may be related to engine incidents.
