In the end, it was a simple rule that has transformed departures at Mumbai airport. Airlines have been asked to shutdown check-in counters 40 minutes before the scheduled departure time, and have the engines ready 15 minutes prior. If they miss their departure slot, they are sent to the end of the queue. Within a few days, most departures are now taking place on time. I myself experienced this on Saturday morning.
Compare this to earlier when aircraft would queue up and take 30+ minutes to take-off. Someone thought about the problem and solved it. We need more such people in India.
Now, if we could only fix some other issues with the airport. First, we need to reclaim the land that bas been lost to squatters so one more runway can be built. The two X-shaped runways limit the handling capacity. Second, landing still means 30+ minutes of hovering time – how can this change? Finally, Mumbai needs a new airport and for this a decision needs to be made now. It has been stuck for many long years.