Frequency of aircraft departures, the number of connections required for a single trip, and the match between available flights and travelers' desired origin and destination points are all important determinants of scheduling convenience. Because data on connections are currently not available in a suitable format, flight stage length is used here to supplement the information on departures.
Flight stage length is the distance between take-off airport and landing airport. If the mix of origin and destination points are held constant, then an increase in flight stage length implies fewer connections are required for a trip and, therefore, higher quality of air passenger services.
The key relation is that departures and flight stage length will tend to move in opposite directions when changes are due to changes in the number of connections. For example, a trip from city A to city B with a connection in city C will have two departures, but generally a shorter average flight stage length, than the direct flight from A to B with a single departure.
|Domestic Flight Availability||Dec-03||Dec-04|
|Revenue aircraft departures (thousands)||686||760|
|Percent change from same month previous year||10.04||10.80|
|Flight stage length (miles)||694||685|
|Percent change from same month previous year||-0.96||-1.31|
NOTES: The current value is compared to the value from the same period in the previous year to account for seasonality.
The data have been adjusted to have a standard 30-day month by multiplying the data for each month by the ratio: 30/(actual days in month).
The data include both transborder and foreign flights by large U.S. carriers, but not include any flights by foreign carriers.
The dramatic changes in the September 2001 data reflect the impact of the terrorist attacks on Sept.11, 2001, on aviation, including several days in which commercial air operations were suspended.
The data reported here excludes small-certificated and commuter carriers that began reporting T100 data in 2002 for comparability with previous issues.
SOURCE: U.S. Department of Transportation, Bureau of Transportation Statistics, Air Carrier Traffic Statistics Monthly, April 2005.