Block Time — Block-to-Block Time

Block Time

Block time is the definitive measure of how long a flight operation takes from a commercial and operational standpoint. Unlike flight time (wheels-up to wheels-down), block time captures the full gate-to-gate duration.

Components of Block Time

Block time = taxi-out time + airborne time (wheels-up to wheels-down) + any airborne holding + taxi-in time.

Why Block Time Matters

Block time is fundamental to: schedule construction (how many rotations can an aircraft complete in a day?), crew duty time calculation and rest requirements (regulated by EASA, FAA and national authorities), aircraft utilisation planning and cost accounting (fuel burn, maintenance cycles and ownership costs are calculated per block hour), published schedule — the times shown on tickets are block-time based.

Block Time vs Flight Time

Flight time (also called air time or flying time) is measured from wheels-off to wheels-on. Block time is always longer. The difference — ground time including taxi — is significant at congested airports. At major hubs, taxi times can add 20–30 minutes to a short block.

Schedule Padding

Airlines add schedule padding (extra time above the actual expected block time) to absorb routine ATC delays and reduce the risk of arriving late. A flight that is scheduled for 2h30m but typically takes 2h15m has 15 minutes of padding. Excessive padding improves OTP statistics but reduces aircraft utilisation efficiency.