*

IndiGo faces staffing crunch due to pilot work hour limits

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Airline cancels at least 90 flights, sources say

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IndiGo blames operational challenges

(Recasts story and adds new details of airport disruption

across three cities)

By Jayshree P Upadhyay, Abhijith Ganapavaram and Dhwani

Pandya

NEW DELHI, Dec 3 (Reuters) - At least 150 flights

operated by India's biggest airline IndiGo were

cancelled and dozens of others delayed on Wednesday, airport

sources said, leaving thousands of travellers stranded and

social media awash with complaints.

According to three airport sources and an IndiGo pilot, the

carrier is facing a shortage of pilots after new government

rules to combat fatigue and boost rest periods for pilots kicked

in on July 1 and November 1, complicating roster management.

In a statement, IndiGo said its operations have been

"significantly disrupted" for the past two days, citing

unforeseen issues including adverse weather conditions and

increased congestion as well as the implementation of updated

crew rostering rules by the Indian government.

That has led to long delays at major airports in the Indian

cities of New Delhi, Mumbai, Hyderabad and Bengaluru, with a

Reuters correspondent inside Delhi airport witnessing scenes of

chaos at IndiGo counters, with passenger anger mounting.

"The 6pm flight is delayed by two hours, and even that gate

has changed four times," said Rakesh Bhanushali, a chartered

accountant from Mumbai, who had been due to fly on Tuesday.

"We are relying on staff completely. Staff are cooperating,

but are frankly saying they are not aware what's happening."

A spokesperson for the airport in Bengaluru said 62 IndiGo

flights had been cancelled on Wednesday.

INDIAN GOVERNMENT HOPING TO BUILD AVIATION SECTOR

India has been banking on a boom in aviation to support

wider development goals, but the latest disruptions throw a

spotlight on the challenges facing its government in balancing

airline interests with pilot welfare.

They also follow an outage at Delhi airport which delayed

hundreds of flights last month.

It was not immediately clear why the larger impact of the

rules change was being felt only this week.

A combination of factors "had a negative compounding impact

on our operations in a way that was not feasible to be

anticipated", the airline said.

IndiGo, which has a domestic market share of more than 60%,

operates over 2,200 flights daily and has been steadily

expanding internationally, challenging rival Air India's

dominance.

India's civil aviation ministry did not respond to Reuters

queries.

IndiGo had an on-time performance of just 35% on Tuesday,

according to government data, the lowest of all Indian airlines.

Its on-time performance this year has typically been above 80%

at major Indian airports.