Aviation regulator DGCA is likely to come out with fresh guidelines on block hours, a yardstick for on-time performance, to remove disparity among airlines. Block hours refer to the moment a commercial aircraft leaves the departure gate until it lands and reaches the arrival gate, or till its engines are working. An airline´s on-time performance as well as facilities and financial compensation to a flyer in case of delay are determined on the basis of block hours. Block hours differ from route to route. Some airlines report good on-time performance by showing additional hours for a particular flight compared to same flights of competing airlines.