We’ve recently noticed that the FlightCancellationStatistics matching total (the total number of originally scheduled flights belonging to this airline/airport) for time_period=today greatly outnumbers the total for prior or future days.

As an example querying today for ident_filter=KPHL
time period, destination, origin, total
twoDaysAgo (577, 578, 1155)
yesterday (590, 582, 1172)
today (1776, 1645, 3421)
tomorrow (504, 503, 1007)
plusTwoDays (415, 418, 834)

Is this a bug or is there a reason the flight totals would be off by this much on day of, but return to normal if looking back a day? We’re attempting to calculate the % of flights delayed/cancelled and this data doesn’t seem to allow for that in its current format.


An event from earlier today allowed erroneous data through our system. Engineers are continuing to address the data errors and correct them.