While most of these commanders quit the airline for better prospects, some of them also parted ways due to the work culture, sources in the Gurgaon-based airline said.
"Around 40 commanders have parted ways with the airline over the past one year as most of them got lucrative offers from Gulf carriers," a source said.
Text messages sent to IndiGo President Aditya Ghosh and airline's PR agency for a comment on the issue did not yield any response.
According to recent DGCA (Directorate General of Civil Aviation) data, Indigo's market share stood at 30.7 percent in July this year over 31.6 percent in June.
Of the around 900 pilots, half of them being commanders, sources said, "the migration accounts for nearly 10 percent of total loss of commanders."
According to sources, Gulf carriers, including Emirates and Qatar Airways, have hired Indian pilots in big numbers in recent months and most of the IndiGo pilots have opted for these airlines.
"Besides tax-free salaries, these airlines also offer a better work environment. Though most of the pilots have left the airline for greener pastures, a few of them also left for better work culture," sources said.
Run by InterGlobe Aviation, IndiGo is one of the two domestic carriers, the other being the Wadia Group-run GoAir, which claim to be profitable.
The airline is likely to hit the capital market next year.
The Foreign Investment Promotion Board (FIPB) has already granted conditional approval to the proposal of InterGlobe Aviation, the holding company of IndiGo, for fresh foreign direct investment in the private carrier.
As per the proposal, equity holding of IndiGo's promoter Rakesh Gangwal through Caelum Investments will be classified as NRI investment and free the FDI limit for fresh investment.     Gangwal through Caelum Investments (incorporated in Delaware, US) holds a 47.88 per cent stake in InterGlobe. Rahul Bhatia owns the remaining stake in the company.
According to FDI rules, foreign companies and foreign airlines are allowed to hold up to a 49 per cent stake in an Indian airline. NRIs are permitted to hold up to 100 per cent in an Indian carrier.
Currently, Gangwal's stake is classified as FDI even though a group of NRIs hold the majority stake in Caelum Investments. As per sources, the proposal is that Caelum will be merged into InterGlobe Aviation. The 147,000 equity shares held by Caelum in InterGlobe Aviation will be cancelled.     

In a cashless transaction, InterGlobe Aviation will issue 147,000 equity shares having face value of Rs 1,000 to NRI owners of Caelum in proportion to the voting units held by them.

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