Types of Delay

ASPM records minutes of delay for five possible causes of flight arrival delays: carrier, weather, NAS, security, and late arrival. The data are provided by the Bureau of Transportation Statistics (BTS) for ASQP flights only. These causes of delay were determined by the Department of Transportation. For additional information, visit "Understanding the Reporting of Causes of Flight Delays and Cancellations from the Bureau of Transportation Statistics Web site. In addition, for flights that show an ASQP reported NAS delay, ASPM reports the most dominant OPSNET delay cause (Weather, Volume, Equipment, Runway, and Other) that matches that ASQP flight.

Carrier Delay

Carrier delay is within the control of the air carrier. Examples of occurrences that may determine carrier delay are: aircraft cleaning, aircraft damage, awaiting the arrival of connecting passengers or crew, baggage, bird strike, cargo loading, catering, computer, outage-carrier equipment, crew legality (pilot or attendant rest), damage by hazardous goods, engineering inspection, fueling, handling disabled passengers, late crew, lavatory servicing, maintenance, oversales, potable water servicing, removal of unruly passenger, slow boarding or seating, stowing carry-on baggage, weight and balance delays.

Late Arrival Delay

Arrival delay at an airport due to the late arrival of the same aircraft at a previous airport. The ripple effect of an earlier delay at downstream airports is referred to as delay propagation.

NAS Delay

Delay that is within the control of the National Airspace System (NAS) may include: non-extreme weather conditions, airport operations, heavy traffic volume, air traffic control, etc. Delays that occur after Actual Gate Out are usually attributed to the NAS and are also reported through OPSNET.

Security Delay

Security delay is caused by evacuation of a terminal or concourse, re-boarding of aircraft because of security breach, inoperative screening equipment and/or long lines in excess of 29 minutes at screening areas.

Weather Delay

Weather delay is caused by extreme or hazardous weather conditions that are forecasted or manifest themselves on point of departure, enroute, or on point of arrival.

OPSNET Delay Cause

Delays to Instrument Flight Rules (IFR) traffic of 15 minutes or more, experienced by individual flights, which result from the ATC system detaining an aircraft at the gate, short of the runway, on the runway, on a taxiway, and/or in a holding configuration anywhere en route.

Such delays include delays due to weather conditions at airports and en route (Weather), FAA and non-FAA equipment malfunctions (Equipment), the volume of traffic at an airport (Volume), reduction to runway capacity (Runway), and other factors (Others). Flight delays of less than 15 minutes are not reported in OPSNET. ASPM reports the most dominant OPSNET delay cause for any flight with an ASQP Reported NAS Delay.