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Airline On-Time Performance in August Improves Over July, Down from Previous Year

Airline On-Time Performance in August Improves Over July, Down from Previous Year


DOT 132-11
Bill Mosley

Thursday, October 13, 2011 - The nations largest airlines recorded a rate of on-time flights in August that was an improvement over Julys mark but down from August 2010s on-time rate, according to the Air Travel Consumer Report released today by the U.S. Department of Transportation (DOT).

Information filed with the Bureau of Transportation Statistics (BTS), a part of DOTs Research and Innovative Technology Administration, shows that the 16 carriers reporting on-time performance recorded an overall on-time arrival rate of 79.3 percent in August, down from the 81.7 percent rate of August 2010 but up from the 77.8 percent recorded in July 2011.

The monthly report also includes data on lengthy tarmac delays, chronically delayed flights, flight cancellations, and the causes of flight delays filed with the Department by the reporting carriers. In addition, the report contains information on reports of mishandled baggage filed by consumers with the carriers, and consumer service, disability and discrimination complaints received by DOTs Aviation Consumer Protection Division. This report also includes reports of incidents involving pets traveling by air, as required to be filed by U.S. carriers.

Tarmac Delays

The carriers filing on-time performance with the Department reported three tarmac delays of more than three hours in August, compared to one in both August 2010 and July 2011.


During August, the carriers canceled 2.5 percent of their scheduled domestic flights, up from both August 2010s 1.0 percent cancellation rate and July 2011s 1.7 percent.

Chronically Delayed Flights

At the end of August, there were 10 flights that were chronically delayed more than 30 minutes late more than 50 percent of the time for three consecutive months.  There were an additional 71 flights that were chronically delayed for two consecutive months. There were no chronically delayed flights for four consecutive months or more. A list of flights that were chronically delayed for a single month is available from BTS (

Causes of Flight Delays

In August, the carriers filing on-time performance data reported that 5.19 percent of their flights were delayed by aviation system delays, compared to 5.69 percent in July; 6.63 percent by late-arriving aircraft, compared to 7.99 percent in July; 5.28 percent by factors within the airlines control, such as maintenance or crew problems, compared to 5.84 percent in July; 0.70 percent by extreme weather, compared to 0.64 percent in July; and 0.04 percent for security reasons, compared to 0.03 percent in July. Weather is a factor in both the extreme-weather category and the aviation-system category. This includes delays due to the re-routing of flights by DOTs Federal Aviation Administration in consultation with the carriers involved.  Weather is also a factor in delays attributed to late-arriving aircraft, although airlines do not report specific causes in that category.

Data collected by BTS also shows the percentage of late flights delayed by weather, including those reported in either the category of extreme weather or included in National Aviation System delays. In August, 39.47 percent of late flights were delayed by weather, up 12.55 percent from August 2010, when 35.07 percent of late flights were delayed by weather, and up 3.30 percent from July when 38.21 percent of late flights were delayed by weather.

Detailed information on flight delays and their causes is available on the BTS site on the World Wide Web at

Mishandled Baggage

The U.S. carriers reporting flight delays and mishandled baggage data posted a mishandled baggage rate of 3.44 reports per 1,000 passengers in August, up from August 2010s rate of 3.42 but down from July 2011s rate of 3.71.

Incidents Involving Pets

In August, carriers reported five incidents involving the loss, death or injury of pets while traveling by air, up from one report in filed in August 2010 but down from July 2011s total of six.  Augusts incidents involved three pet deaths, one injury and one lost pet. 

Complaints About Airline Service

In August, the Department received 1,471 complaints about airline service from consumers, up 18.1 percent from the 1,200 complaints received in August 2010 and up 10.3 percent from the total of 1,285 filed in July 2011.

Complaints About Treatment of Disabled Passengers

The report also contains a tabulation of complaints filed with DOT in August against airlines regarding the treatment of passengers with disabilities.  The Department received a total of 47 disability-related complaints in August 2011, down from both the 71 disability complaints received in August 2010 and the total of 56 filed in July 2011.

Complaints About Discrimination

In August, the Department received 12 complaints alleging discrimination by airlines due to factors other than disability such as race, religion, national origin or sex down from the total of 17 filed in August 2010 but up from the five discrimination complaints received in July 2011.

Consumers may file their complaints in writing with the Aviation Consumer Protection Division, U.S. Department of Transportation, C-75, W96-432, 1200 New Jersey Ave. SE, Washington, DC 20590; by voice mail at (202) 366-2220 or by TTY at (202) 366-0511; or on the web at

Consumers who want on-time performance data for specific flights should call their airlines reservation number or their travel agent.  This information is available on the computerized reservation systems used by these agents.  The information is also available on the appropriate carriers website.

The Air Travel Consumer Report can be found on DOTs World Wide Web site at It is available in pdf and Microsoft Word format.

Air Travel Consumer Report August 2011
Key On-Time Performance and Flight Cancellation Statistics

Based on Data Filed with the Bureau of Transportation Statistics by the 16 Reporting Carriers


79.3 percent on-time arrivals

Highest On-Time Arrival Rates

1. Hawaiian Airlines 94.8 percent

2. Alaska Airlines 90.8 percent

3. Southwest Airlines 83.4 percent

Lowest On-Time Arrival Rates 

1. JetBlue Airways 61.6 percent

2. US Airways 74.2 percent

3. Continental Airlines 74.3 percent

Flights with Longest Tarmac Delays

1. Delta Air Lines flight 897 from New York JFK to Minneapolis/St. Paul, 8/19/11 delayed on tarmac 219 minutes

2. Delta Air Lines flight 562 from New York JFK to San Francisco, 8/19/11 delayed on tarmac 189 minutes

3. United Airlines flight 562 from Dallas/Fort Worth to San Francisco, 8/9/11 delayed on tarmac 183 minutes

(There were only three flights with tarmac delays of more than three hours in August)

Highest Rates of Canceled Flights

1. JetBlue Airways 7.0 percent

2. American Eagle Airlines 4.5 percent

3. ExpressJet Airlines 3.9 percent

Lowest Rates of Canceled Flights

1. Hawaiian Airlines 0.1 percent

2. Alaska Airlines 0.5 percent

3. Frontier Airlines 0.6 percent