According to data released by UK's OAG Aviation Worldwide Ltd, the sector which connects the business capital of Mumbai with the political establishment in Delhi is next only to South Korea's Seoul Gimpo-Jeju airports (64,991 flights) and Australia's Melbourne-Sydney airports (54,519).
The sector saw heavy air traffic between the two airports in 2017, leaving behind San Francisco-Los Angeles and Cape Town-Johannesburg air routes.
Two other Indian domestic sectors routes also featured in the Top 20 Busiest Domestic routes list. While Bengaluru-Delhi sector was ranked 11 on the list with 29,427 flights, the Bengaluru-Mumbai route was ranked 16 with 23,857 flights.
Surprisingly, four out of the top five busiest air routes is in the Asia-Pacific region. Los Angeles-San Francisco sector was the only North American entry in the top 10 list that did not feature a single European destination.
But when it comes to punctuality, the Mumbai-Delhi route recorded on-time performance (OTP) of 59.14 % - one of the worst among the 20 busiest air routes.
Air route connecting Japanese cities Tokyo Haneda-Osaka topped the list witnessing an OTP of 90.40 %. The route which was listed as the 17th busiest in the OAG list saw flights departing and landing within 15 minutes of their scheduled time.
Jeju-Seoul, the busiest route, had an average on-time performance (OTP) of 74.06 %, the report added.