LO
ConstraintProcess & self-service2023-08-28
When the UK's flight-plan system failed on 28 August 2023, processing fell from about 800 plans an hour to about 60 done by hand; the CAA's review judged scaling manual capacity up not justified
Air traffic controlleroccupation page →
Event date / reported
2023-08-28 · reported 2024-05-31
Evidence stage
ConstraintFailure, rollback, regulation or cost is suppressing adoption. Can lower an assessment or widen its uncertainty.
Tasks this bears on
When the plan breaks
An emergency, a radio failure, a runway incursion, a line of weather that closes the arrival gate — the minutes where the standard procedure has run out and someone has to build a new plan while the old one is still moving.
Still human-led✓ Evidence-backed
Where this applies
The final report of an independent panel commissioned by the UK Civil Aviation Authority into the failure of the national air traffic service's flight-plan processing system. Once the backup system went into maintenance mode, automated processing stopped and the remaining capacity was entirely manual, cutting the number of flight plans processed from typically 800 an hour at busy times to about 60; manual input could not support flight operations without restrictions on traffic. The operator estimated that matching 80 percent of automated capacity by hand would take about 200 more staff at £10.75m a year, and the panel concluded that expanding manual capacity that far is not justified. The manual work was flight-data entry; controllers handled traffic under the resulting flow restrictions.
What this means
When the automation stopped, the work fell back on people, and people alone could handle under a tenth of it. The review chose not to pay for a manual fallback large enough to replace it — so the non-normal day is handled by restricting traffic and by controllers working with missing data, not by keeping a hidden manual capacity.
What it does not yet show
One failure in one country's system; the manual work described is flight-data entry, and the report does not measure controllers' workload that day.
What you can check
Open CAA CAP2993 (final report) and find "typically 800 per hour during a busy period to approximately 60".
Does it change the assessment?
No. The impact index is never moved by a single event. What this record did: the 1 linked task judgement above now rest on evidence instead of inference.
Source
UK Civil Aviation Authority — CAP2993, Independent Review of NATS (En Route) Plc's Flight Planning System Failure on 28 August 2023, Final report (31 May 2024) · verified 2026-09-29 · Claude (VOLO agent) · interpreted 2026-09-29 · Claude (VOLO agent)
Primary source — published by the party that did this, or the authority of record. No co-signature needed.