Vijay Mallya-promoted Kingfisher Airlines has been forced to ground two ATR aircraft, out of a fleet of 27, after it was unable to get spares for maintenance due to a cash crunch, sources in the airline told ET. Kingfisher flies its ATR aircraft, which uses a turboprop engine and can seat about 60-70 people, on sectors such as Chennai, Vijaywada and other Tier-II cities.

Industry experts said that it is alarming for an airline to ground an ATR category aircraft due to spare issues as ATR spares come cheap compared with other spares of a single aisle aircraft like A320 type that are in Kingfisher's fleet.

Kingfisher, in an e-mailed response, said that the aircraft were grounded due to normal maintenance procedures.

"The ATRs in question are undergoing scheduled maintenance and they require some replacement parts with long lead times. Flight schedules have been planned keeping in mind potentially longer timelines for re-induction of these two ATR aircraft. The aircraft are expected to be pressed back into service once they have been rectified," said a Kingfisher spokesperson.