How OTP is calculated
OTP = flights on time ÷ flights operated × 100
- Departure OTP compares actual with scheduled departure time.
- Arrival OTP compares actual with scheduled arrival time.
- The common threshold is 15 minutes. Some reports also track stricter or looser thresholds (for example within 0 or 30 minutes) to see the full distribution of delays.
Sources differ on details such as whether a flight exactly 15 minutes late is on time and whether cancelled flights count as late. When comparing OTP figures, check the definition behind them.
How airlines use it
- Daily operations: the operations centre watches OTP by station and by hour to spot problems early.
- Root cause: OTP is broken down by route, station, aircraft type and IATA delay code to find where delays start and how they spread to later flights.
- Schedule planning: routes with persistently low OTP may need more turn time or block time.
- Reputation: published OTP rankings influence how passengers and partners see an airline.
OTP in Wireum Insights
Wireum Insights shows on-time performance by route, station, aircraft type and delay code, next to IROPS and the live fleet, so operations and management teams see punctuality and its causes in one place.