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Airline Delays Called Undercounted Because of Data Flaws

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Dec. 20 (Bloomberg) -- Flight delays are significantly undercounted at some of the biggest U.S. hub airports, skewing airlines’ on-time performance statistics disclosed to travelers, according to an inspector general’s report.

Statistics for carriers such as American Airlines Group Inc., Delta Air Lines Inc. and United Continental Holdings Inc. don’t include late arrivals by regional partners that account for almost one-fourth of U.S. flights and are exempt from reporting delays, the Transportation Department report said.

Philadelphia International Airport, for example, had 38,000 tardy flights in 2012, more than twice the official count of 13,800 published by the Department of Transportation’s Bureau of Transportation Statistics, the study found.

“BTS’s published flight delay data present the public with an incomplete picture of the number of delays that actually occur at a given airport or are generated by all carriers,” the report said.

Republic Airways Holdings Inc.’s Chautauqua Airlines, which flies for all three of those major carriers, isn’t required to report delays because its passenger revenues are less than 1 percent of the industry total, according to the report.

While regional airlines conduct more than half of all flights, they carry fewer people per plane and therefore generate less revenue than major carriers. Carriers that don’t report delays operate 24 percent of scheduled flights, said the report, by Jeffrey Guzzetti, assistant inspector general for aviation audits.

178,000 Delays

In 2012, almost 178,000 flights that arrived at least 15 minutes late at the U.S.’s largest 35 airports weren’t included in the Transportation Department’s reports, the inspector general found. The number of delays at those airports would swell by 25 percent if all late flights were included.

Delays would increase by at least 50 percent at 10 of those 35 airports if all carriers were included, the IG found. Those airports include Detroit Metropolitan, Charlotte/Douglas International and Washington’s Reagan National.

Regionals tend to get more delays during periods of congestion because rules crafted by the FAA and major carriers often favor larger planes with more passengers, George Donohue, an engineering professor at George Mason University in Fairfax, Virginia, said in an interview.

“The regionals are the ones that get hammered,” said Donohue, a former associate administrator at the FAA who has studied airline on-time data.

Changes Expected

The BTS expects to propose changing its rules to require broader reporting early next year, Bill Adams, a DOT spokesman, said in an e-mail. “This builds on the department’s other steps to reduce delays, such as its rules on tarmac delays that have virtually eliminated the long waits aboard aircraft that passengers used to experience too frequently,” Adams said in the statement.

If reporting requirements were changed to include all regional airlines flying for a major carrier, along with airlines that have as much as 0.5 percent of total industry revenues, the agency would capture 92 percent of scheduled passenger flights, according to the report. It now receives 76 percent of flight data.

Fifteen airlines report delay data to the BTS. One regional carrier, Mesa Air Group Inc.’s Mesa Airlines, voluntarily reports its late flights.

Tardy Flights

Andrea Huguely, a spokeswoman for American, Morgan Durrant, a spokesman for Delta, and Megan McCarthy, a spokeswoman for United, didn’t immediately respond to e-mail requests for comment. Kelly Murphy, a spokeswoman for the Washington-based Regional Airline Association, also didn’t respond to an e-mail.

The report says tardy flights fell, by 33 percent from 2000 to 2012, using the government’s flawed data. It didn’t say what the trend would be if all delays had been counted.

The decline occurred as airlines shrunk, airports added runways and the U.S. Federal Aviation Administration introduced new air-traffic technology.

Delay totals are also depressed because carriers have added time to their published schedules.

Flying Time

The amount of time airlines scheduled for flights exceeded the actual flying time without delays on 98 percent of 2,021 routes examined by the IG.

While the practice has reduced delays on chronically late flights, it hasn’t reduced congestion at airports where carriers have scheduled more flights than can be accommodated, the report found.

In separate reports, the IG also found flaws in an FAA safety-data collection program and a contract to train the agency’s air-traffic controllers.

While the FAA has improved its ability to collect raw airline data in search of safety trends, it doesn’t allow its inspectors to access the information, according to the report.

In a $859 million contract with Raytheon Co. to train controllers, the FAA hasn’t achieved half its goals, the IG found. While the agency hoped to reduce training times, it increased by 41 percent from 2009 to 2012 under the contract, according to the report.

To contact the reporter on this story: Alan Levin in Washington at

To contact the editor responsible for this story: Bernard Kohn at

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