Domestic air passenger volume surged 26 per cent in April to 11.51 million over the year-ago period driven by the tourists season, which began from the previous month, according to DGCA data released today.Indian carriers together flew 11.51 million passengers in April this year as against 91.34 million in the same month last year, thereby logging a 24.1 per cent growth, Directorate General of Civil Aviation (DGCA) data showed.The Gurugram-based IndiGo remained the market leader, having flown more than four out of every 10 passengers as it carried 4.58 million passengers during the month while rival SpiceJet continued to see the highest seat occupancy across its aircraft market at 95.5 per cent.The passenger load factor in April has shown increasing trend compared to the previous month primarily due to beginning of tourist season, the DGCA said.Besides flying the maximum number of passengers, IndiGo also recorded the highest on time performance (OTP) with 86.6 per cent of its flights arriving and departing as per schedule from four metro airports, Mumbai, Delhi, Hyderabad and Bengaluru.It was followed by SpiceJet and GoAir (86.1 per cent each), Jet Airways along with its subsidiary JetLite (82.9 per cent) and Vistara (78.4 per cent). This was Jet Airways best OTP in several months as it was hovering in the range of 50-60 per cent only.Disinvestment-bound Air India recorded the lowest OTP from the four airports with nearly a quarter of its flights failing to depart or arrive on the scheduled time from the four airports."SpiceJet has yet again recorded the highest passenger load factor in the industry. For three years in a row, it has flown with loads in excess of 90 per cent," Shilpa Bhatia, chief sales and revenue officer at SpiceJet said.The overall cancellation rate of scheduled domestic airlines for the month of April stood at 0.64 per cent with new entrants in the regional flight space Air Deccan cancelling 45.60 per cent of their total flights followed by New Delhi-based Zoom Air, which did not operate nearly one-thirds of its services during the months, according to DGCA data.Interestingly, Indian carriers paid a whopping sum of Rs 2.36 crore in compensation to passengers for denied boarding, flight cancellations and delays, the data showed.