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Technical Directive #14 - On-Time Reporting

Technical Directive #14 - On-Time Reporting

Research and Innovative Technology Administration
Bureau of Transportation Statistics
Office of Airline Information
Title 14 Code of Federal Regulations Part 234
Amended, Technical Directive #14
Issue Date: October 2, 2006
Effective Date: January 1, 2007

This technical directive replaces Technical Directive #13. Pinnacle Airlines will be required to submit Airline Service Quality Performance Reports, while ATA and Hawaiian Airlines have fallen below the one-percent scheduled domestic passenger revenue threshold and are no longer required to report (14 CFR 234.3). Hawaiian Airlines indicates that it will report as a volunteer carrier. St. Louis Lambert and Portland International airports are added back to the Reportable Airports List while Pittsburgh International is deleted from the list.

The Office of Airline Information issues accounting and reporting directives to update the reporting air carrier and reportable airport lists, and to clarify the reporting regulations when the need arises.

I. Introduction
II. Applicability
III. Definitions
IV. Data Requirements for DOT On-Time Disclosure Reports
V.Report Format and Instructions for On-Time Disclosure Reports and Mishandled-Baggage Reports
VI.Submission of Reports
VII.Record Retention
VIII. Data Requirements and Instructions for CRS Disclosure
IX. Reporting the Causes of Cancelled and Delayed Flights
X. Security Screening

I. Introduction

Part 234 of the Department of Transportation's (Department's) Regulations, "Airline Service Quality Performance Reports," requires certain U.S. air carriers to submit scheduled flight performance data and mishandled-baggage information to the Department, and to provide on-time performance codes to Computer Reservation System (CRS) vendors. These data are used to monitor each carrier's on-time performance and baggage handling, and to provide information to consumers. The scheduled flight performance data are filed electronically. The mishandled-baggage information is submitted as a one-page hardcopy report with the required certification and transmittal letter. The on-time performance codes are filed with the Department, and supplied to CRS vendors in accordance with the procedures set forth in 234.8 and 234.9 and in this Technical Directive.

II. Applicability

1. Each reporting air carrier providing scheduled domestic passenger operations at a reportable airport will file "On-Time Flight Performance Data," if its share of the industry's total domestic scheduled-service passenger revenues exceed one percent, based on Form 41 data for the 12 months ended June 30. Each year, the Office of Airline Information updates the list of reporting air carriers.

2. For calendar year 2007, 19 air carriers are required to report. Carriers that generated $743 million or more in domestic schedule passenger revenues in the 12 month period ended June 30, 2006, are required to submit Airline Service Quality Performance Reports. The following is a list of the reporting carriers:

AirTran
Alaska
America West
American
American Eagle
Atlantic Southeast
Comair
Continental
Delta
ExpressJet Airlines d/b/a Continental Express
Frontier
JetBlue
Mesa Airlines
Northwest
Pinnacle Airlines d/b/a Northwest Airlink
SkyWest
Southwest
United
US Airways

Also, Hawaiian and Aloha Airlines will report voluntarily. US Airways' and America West's reports are combined under the US Airways code.

3. The reportable airports with respect to which data must be submitted to the Department are those airports located in the 48 contiguous states enplaning 1 percent or more of the industry's domestic scheduled-service passengers, as reported on the Form 41 Schedule T-100. The Office of Airline Information updated T-100 enplanements for the 12 months ended June 30, 2006. For calendar year 2007, there are 32 reportable airports, which met the threshold of over 6.5 million passengers.

AIRPORT CODE
Atlanta - Hartsfield Jackson ATL
Baltimore/Wash. Int'l Thurgood.Marshall BWI
Boston - Logan International BOS
Charlotte - Douglas CLT
Chicago - Midway MDW
Chicago - O'Hare ORD
Cincinnati Greater Cincinnati CVG
Dallas-Fort Worth International DFW
Denver - International DEN
Detroit - Metro Wayne County DTW
Fort Lauderdale Hollywood International FLL
Houston - George Bush International IAH
Las Vegas - McCarran International LAS
Los Angeles International LAX
Miami International MIA
Minneapolis-St. Paul International MSP
Newark Liberty International EWR
New York - JFK International JFK
New York - LaGuardia LGA
Oakland International MCO
Orlando International OAK
Philadelphia International PHL
Phoenix - Sky Harbor International PHX
Portland International PDX
Salt Lake City International SLC
St. Louis Lambert International STL
San Diego Intl. Lindbergh Field SAN
San Francisco International SFO
Seattle-Tacoma International SEA
Tampa International TPA
Washington - Reagan National DCA
Washington - Dulles International IAD

4. The reportable flight operations for which data must be submitted to the Department are all scheduled nonstop domestic passenger operations by a reporting air carrier to or from any reportable airport.

5. In addition to the required data for each reportable flight which must be submitted to the Department, a reporting carrier may also submit the required data for every other nonstop domestic passenger flight it holds out to the public pursuant to a published schedule. In addition, any carrier not included in paragraph II. 2. of this Technical Directive may voluntarily become a reporting carrier and submit Form 234 for its reportable flights for every nonstop domestic passenger flight it holds out to the public pursuant to a published schedule, provided that the BTS Assistant Director, Airline Information (AI), is advised beforehand. Such voluntary data must be submitted for a minimum of 12 consecutive months. The voluntary submission must meet the exact reporting specifications set forth in this directive. Volunteering carriers that wish to discontinue reporting after one year must advise the Assistant Director, AI, a minimum of 30 days before discontinuance, so that the necessary changes can be made to the Department's data programs.

6. Changes in reporting air carriers and reportable airports will be made as necessary by the Assistant Director, AI, under authority delegated in 385.19 of the Department's regulations.

III. Definitions

Definitions used in this directive include those in 234.2 as well as the following:

1. 'CRS' means a 'system' as defined in 14 CFR 255.3 of the Departments regulations,

2. 'Domestic operation' means a flight operation within or between the 50 states of the United States, the District of Columbia, the Commonwealth of Puerto Rico and the U.S. Virgin Islands, and the territories and possessions of the United States. Transborder operations are not included.

3. 'Flight' for purposes of the data to be reported to the Department, means one or more scheduled nonstop operations identified by a specific flight number in conjunction with a specific origin-destination city-pair designation; e.g., flight 102 DCA-ATL-MIA includes two separate flights (DCA-ATL, ATL-MIA).

4. 'Flight' for the purposes of CRS disclosure, means nonstop operations as defined above, plus scheduled one-stop and multi-stop operations identified by a specific flight number in conjunction with a specific origin-destination city-pair designation; e.g., flight 102 DCA-ATL-MIA includes three separate flights for purposes of CRS disclosure (DCA-ATL, ATL-MIA, DCA-MIA).

5. 'Flight operation' means a specific operation of a given flight on a given day; e.g., if flight 102 DCA-ATL operated daily during the month of July, then it had 31 flight operations in July.

6. 'Gate arrival time' is the instance when the pilot sets the aircraft parking brake after arriving at the airport gate or passenger unloading area. If the parking brake is not set, record the time for the opening of the passenger door.

7. 'Gate departure time' is the instance when the pilot releases the aircraft parking brake after passengers have loaded and aircraft doors have been closed. If passengers were boarded without the parking brake being set, record the time that the passenger door was closed.

IV. Data Requirements for DOT On-Time Disclosure Reports

1. Each reporting air carrier will file Form 234 for each calendar month. Each report will include all nonstop domestic passenger scheduled flight operations by the reporting carrier that serve one or more of the reportable airports.

2. For each nonstop flight operation serving a reportable airport, the following data elements will be reported:

A. Carrier (Two Letter Code)
B. Flight Number
C. Departure Airport (Three Letter Code)
D. Arrival Airport (Three Letter Code)
E. Date of Flight Operation (Year/Month/Day)
F. Day of Week of this Flight Operation (Monday = 1...Sunday = 7)
G. Scheduled Departure Time as Shown in the Official Airline Guide (OAG) Pursuant to § 234.4(f)
H. Scheduled Departure Time as Shown in CRS Selected by the Carrier as its Data Source Pursuant to § 234.4(f)
I. Gate Departure Time (Actual) in Local Time
J. Scheduled Arrival Time as Shown in the OAG
K. Scheduled Arrival Time as Shown in CRS
L. Gate Arrival Time (Actual) in Local Time
M. Difference in Minutes Between OAG and Scheduled Departure Time: G minus H
N. Difference in Minutes Between OAG and Scheduled Arrival Time: J minus K
O. Scheduled Elapsed Time Per CRS in Minutes: K Minus H
P. Actual Gate to Gate Time in Minutes: L Minus I
Q. Departure Delay (Difference in Minutes Between Actual Departure Time and CRS Scheduled Departure Time): I Minus H
R. Arrival Delay (Difference in Minutes Between Actual Arrival Time and CRS Scheduled Arrival Time): L Minus K
S. Elapsed Time Difference (Difference in Minutes Between Actual Elapsed Time and CRS Scheduled Elapsed Time): P Minus O
T. Wheels-Off Time (Actual) in Local Time
U. Wheels-On Time (Actual) in Local Time
V. Aircraft Tail Number
W. Cancellation Code
X. Minutes late for delay code E
Y. Minutes late for delay code F
Z. Minutes late for delay code G
AA. Minutes late for delay code H
AB. Minutes late for delay code I

CANCELLATION CODES
A-Carrier Caused
B-Weather
C-National Aviation System
D-Security

DELAY CODES
E-Carrier Caused
F-Weather
G-National Aviation System
H-Security
I-Late Arriving Aircraft

3. The data format for the elements listed in paragraph 2 above will comply exactly with either one of two flight record field specifications set forth in section V. Report Format and Instructions for On-Time Disclosure Reports and Mishandled-Baggage Reports.

4. All scheduled and actual arrival and departure times will be reported in local time using a 24 hour clock; e.g. 3:15 p.m. will be 15:15, midnight is 24:00, and one minute after midnight is 00:01. In using local time, the reporting carrier must adjust for time zone differences in computing data elements O, P, and S.

5. Times should be reported in whole minutes; e.g. two hours equals 120 minutes.

6. Flight operations that begin and end in different months will be reported in the month in which they begin.

7. Extra-section, nonscheduled and charter flights will not be reported.

8. Flight cancellation information will be incorporated in the appropriate flight record for the canceled flight operations by entering zero in the data field I (Gate Departure Time), zero in data field L (Gate Arrival Time), zero in data field T (Wheels-Off Time), and zero in data field U (Wheels-On Time). Aircraft tail number must be reported for canceled flights; however, when a flight has been canceled before a specific aircraft has been assigned to that flight, you would leave field V (Aircraft Tail Number) blank.

9. Information on flights which operated but were diverted to an alternate destination will be incorporated in the appropriate flight record for the diverted flight operation by entering the actual departure time in data field I (Gate Departure Time), zero in data field L (Gate Arrival Time), and zero in data field U Wheels-On Time (Actual).

10. All numeric fields for which data are unavailable will be zero-filled.

11. Any data field resulting from calculations involving such zero-filled fields will also be zero-filled.

12. For data fields Q, R, and S use positive numbers to indicate time in minutes for departure/arrival/elapsed time delays. Use negative numbers to indicate time in minutes for departures, arrivals ahead of schedule and elapsed times less than scheduled.

13. Fields M, N, Q, R, and S have positive and negative values:

a. When reporting in the ASCII comma delimited format, as described in the specifications set forth in section V.3. Email Attachment Reporting Requirements, these fields will indicate this attribute as the actual numeric value, preceded by a "-" negative sign when the number is negative.

14. Reporting numeric data:

a. When reporting in the ASCII comma delimited format, leading zeros are NOT necessary for "Minutes" fields (M, N, O, P, Q, R, S, X, Y, Z, AA, and AB).

b. Leading zeros will be used for "Time" fields (G, H, I, J, K, L, T, and U). These fields use a 24 hour clock and will use a leading zero to show 0800 for 8:00 AM (2000 for 8:00 PM.)

V. Report Format and Instructions for On-Time Disclosure Reports and Mishandled-Baggage Reports

1. Transmittal Letter.

An electronic version of the transmittal letter will accompany each carriers data submission. The transmittal letter must identify the carrier and month and year for which the data are being submitted, and contain the following information:

a. A certification statement identifying an appropriate official of the reporting carrier. The certification statement will read:

I, (Name) and (Title), of the above-named air carrier, certify that the e-mail attachments having the BTS Form 234 "On-Time Flight Performance Report" and the Mishandled-Baggage Report are to the best of my knowledge and belief, true, correct, and complete reports for the period stated.

Date:

Signature:

Name (Please Type or Print):

b. The name(s) and telephone number(s) of the carriers staff who can be contacted to resolve problems regarding both carrier data and technical matters.

c. For control purposes, a statement indicating the total number of flight operations and unique flight numbers in the Form 234 submission.

d. For the initial submission, a description of the data submitted, specifying whether the email attachment includes data for only reportable airports or for all domestic scheduled nonstop flight operations.

e. For the initial submission and for subsequent changes, a statement identifying the source of the scheduled arrival and departure times used in the report: (1) Official Airline Guide in effect on (date) and (2) the name of the computer reservation system used for reporting purposes, pursuant to 234.4(f).

f. When reporting by e-mail, the transmittal letter may be submitted as an email attachment, so long as the Reporting Carriers Certifying Officials contact information is included.

2. Mishandled-Baggage Report.

The reporting carriers Mishandled Baggage Report shall be made into an electronic document separate from the transmittal letter.

This report will show the mishandled-baggage information for the reporting month and include the following items:

Name of Carrier

Month and Year of the Data included in the Report

Number of Domestic Scheduled Passengers Enplaned

Number of Mishandled-Baggage Reports Filed with Carrier

3. E-mail Attachment Reporting Requirements.

a. Form 234, "On-Time Flight Performance Report," shall be filed in the ASCII comma delimited format by e-mail attachment. The data will be reported without summarization, with a separate flight record for each reportable operation. Flight records will be sequenced by date of flight (field E) within market (fields C and D), within flight number (field B).

b. The format for ASCII submissions will be:

(1) Comma Delimited:

Within each record, fields are to be separated with commas.

This is NOT a comma-separated-values (.csv) format. It does NOT have formulas, quotes around text fields, or other special embedded codes such as would be made by Microsoft Excel.

Note: When a flight has been canceled before a specific aircraft has been assigned to that flight, you would leave field V (Aircraft Tail Number) blank, resulting in adjacent commas (e.g. ,, ).

(2) File Naming Convention: (File Name is Case Sensitive)

The file will be named: CCyyyymm.DD

Where uppercase CC is the two character IATA Carrier Code.

Where yyyy is the numeric century and year of the data reported.

Where mm is the numeric month of the data reported.

The uppercase ".DD" is the literal file extension required for system identification at the Office of Airline Information.

Example: AA200301.DD = American Airlines, 2003, January

(3) Field Specifications for Reporting on Diskette or by Email Attachment (ASCII)

Field Description Type Length Comments
A Carrier code Character 2 Two letter IATA code
B Flight number Character Max length of 4  
C Origin airport code Character 3 Three letter Airport code
D Destination airport code Character 3 Three letter Airport code
E Date of flight operation Num 8 Format ccyymmdd
F Day of the week of flight operation Num 1 Mon = 1, Sun = 7
G Scheduled departure time as shown in Official Airline Guide(OAG) Num 4 Local time 24 hour clock
H Scheduled departure time as shown in CRS(selected by the Carrier) Num 4 Local time 24 hour clock
I Gate departure time (actual) Num 4 Local time 24 hour clock
J Scheduled arrival time per OAG Num 4 Local time 24 hour clock
K Scheduled arrival time per CRS Num 4 Local time 24 hour clock
L Gate arrival time (actual) Num 4 Local time 24 hour clock
M Difference between OAG and CRS scheduled departure times Num Max length of 4 In minutes (2 hours=120 min) G minus H
N Difference between OAG and CRS scheduled arrival times Num Max length of 4 In minutes J minus K
O Scheduled elapsed time per CRS Num Max length of 4 In minutes K minus H
P Actual gate-to-gate time Num Max length of 4 In minutes L minus I
Q Departure delay time (actual minutes CRS) Num Max length of 4 In minutes I minus H
R Arrival delay time (actual minutes CRS) Num Max length of 4 In minutes L minus K
S Elapsed time difference (actual minutes CRS) Num Max length of 4 In minutes P minus O
T Wheels-off time (actual) Num 4 Local time 24 hour clock
U Wheels-on time (actual) Num 4 Local time 24 hour clock
V Aircraft tail number Character 6  
W Cancellation code Character 1 Values are A, B, C, D
X Minutes late for Delay Code E Carrier Caused Num Max length of 4 In minutes
Y Minutes late for Delay Code F Weather Num Max length of 4 In minutes
Z Minutes late for Delay Code G National Aviation System (NAS) Num Max length of 4 In minutes
AA Minutes late for Delay Code H Security Num Max length of 4 In minutes
AB Minutes late for Delay Code I Late Arriving Flight (Initial) Num Max length of 4 In minutes

CANCELLATION CODES:
A Air Carrier
B Weather
C National Aviation System (NAS)
D Security

DELAY CODES:
E Carrier Caused
F Weather
G National Aviation System (NAS)
H Security
I Late Arriving Flight (Initial)

VI. Submission of Reports

1. Carriers shall send electronic copies of their reports to: ontime.support@dot.gov

2. Additional options for correspondence include:

Address: The address for the Form 234 data submission and the Mishandled-Baggage Report is:

U.S. Department of Transportation
Research and Innovative Technology Administration
Bureau of Transportation Statistics
Office of Airline Information, RTS-42, Room 4125
400 Seventh Street, S.W.
Washington, DC 20590-0001

Fax: The fax number for the Office of Airline Information is (202) 366-3383.

For assistance, carriers should contact Mr. Bernie Stankus at 202-366-4387.

3. Due Dates. The due date for Form 234 and the Mishandled-Baggage Report is 15 days after the applicable reporting month, i.e., data for the month of March are due by April 15. If the 15th day falls on a weekend or Federal holiday, the due date will be the next workday.

4. Enforcement. Penalties for late filing or noncompliance with these reporting requirements will be assessed in accordance with 49 U.S.C. 46310.

5. Missing or Incomplete Records. Any carrier subject to this directive which does not file the required data for any period, or files incomplete data, will submit a sworn statement of an officer that the carrier was unable to provide the data because it did not have and could not obtain the necessary records. That statement, as well as the veracity of the information and the data submitted, will be subject to 18 U.S.C. 1001, regarding criminal penalties for false statements made to a government agency. The statement will be filed with the Director, Office of Airline Information, at the address in paragraph 1 above, three days prior to the due date.

6. Special Circumstances. Requests for waivers, exceptions, extensions, or other considerations will be submitted in writing to the Director, Office of Airline Information, at the address in paragraph 1 above.

VII. Records Retention

Form 234 and the Mishandled-Baggage Report are statistical reports. The record retention requirements for statistical reports are governed by Part 249, "Preservation of Air Carrier Records" of the Departments Regulations. Specifically, 249.20-6 requires the information supporting a statistical report to be maintained by the carrier for three years.

VIII. Data Requirements and Instructions for CRS Disclosure

As required by 234.8 of the Departments Regulations, each reporting carrier providing data pursuant to this directive will calculate an on-time performance code for each reportable (nonstop) flight included in its monthly data submission to the Department, and for each one-stop or multi-stop flight that includes a reportable flight segment as specified below. That calculation will be carried out as follows:

1. Each reporting carrier will compute the arrival delay in minutes for each reported (nonstop) flight operation in its monthly data submission by subtracting the scheduled arrival time for each flight operation per its CRS records (data field K) from the actual gate arrival time (data field L).

2. Using the data derived from the computation in paragraph 1 above, each reporting carrier will calculate, for each nonstop flight in its data submission, the percent of that flights operations that were on-time during the month (i.e., arrived sooner than the CRS scheduled arrival time + 15 minutes). The calculation will be performed by dividing the number of reported operations of each flight that arrived less than 15 minutes after the scheduled arrival time, by the total number of reported operations of that flight during the month.

3. Each reporting carrier will convert the percentage derived from the computations in paragraph 2 into a one digit CRS on-time performance code for each reportable flight operated during the month as follows:


Percent of operations of the flights that were on-time CRS on-time performance code
90 to 100 9
80 to 89.9 8
70 to 79.9 7
60 to 69.9 6
50 to 59.9 5
40 to 49.9 4
30 to 39.9 3
20 to 29.9 2
10 to 19.9 1
0 to 9.9 0

4. New flights as defined in 234.2 for which no on-time percentage is available yet will be designated with the CRS data code "N" (no record).

5. Each reporting carrier will include the appropriate one digit CRS code (0 through 9 or "N") as a standard data element in each flight schedule it provides the OAG and/or any CRS vendor(s), for every reportable flight.

6. In addition, using the procedure illustrated in this paragraph, each reporting carrier will include the appropriate one digit CRS code (0 through 9 or "N") as a standard data element in each flight schedule it provides the OAG and/or any CRS vendor(s), for every one-stop or multi-stop flight, or portion thereof, that includes a reportable flight as a final flight segment.

Examples:

If flight 102 operates EWR-DCA-ATL-MIA, provide the on-time performance codes for:

102 EWR-DCA (calculated per paragraphs 1-4 above)
102 DCA-ATL (calculated per paragraphs 1-4 above)
102 ATL-MIA (calculated per paragraphs 1-4 above)
102 EWR-ATL: assign 102 DCA-ATL performance code
102 EWR-MIA: assign 102 ATL-MIA performance code
102 DCA-MIA: assign 102 ATL-MIA performance code

If flight 103 operates BUF-SYR-EWR-DCA, provide on-time performance codes for:

103 SYR-EWR (calculated per paragraphs 1-4 above)
103 EWR-DCA (calculated per paragraphs 1-4 above)
103 BUF-EWR: assign 103 SYR-EWR performance code
103 BUF-DCA: assign 103 EWR-DCA performance code
103 SYR-DCA: assign 103 EWR-DCA performance code

If flight 104 operates MKE-DTW-CMH-LEX, provide on-time performance codes for:

104 MKE-DTW (calculated per paragraphs 1-4 above)
104 DTW-CMH (calculated per paragraphs 1-4 above)
104 MKE-CMH: assign 104 DTW-CMH performance code

7. A flight that is not a new flight will be assigned the on-time performance code calculated for the flight that it replaces, even if the two flights do not have the same flight number.

8. No later than the 15th day of each month, each reporting carrier will deliver or arrange to have delivered to its CRS vendor(s), updated on-time performance codes. If a carrier relies on a third party to supply such flight information to CRS vendor(s), the carrier will provide their flight information, including the appropriate CRS on-time performance codes, at the same time that the carrier submits its monthly flight data to the Department.

9. The calculation and assignment of on-time performance codes for flights other than reportable flights, as permitted in 234.10, will follow the procedures set forth above. Carriers are required to perform those calculations only for reportable flights, and for one-stop or multi-stop flights, or portions thereof, that include a reportable flight as a final flight segment, but may do so for all flights at their option.

10. No carrier may provide on-time performance codes to the OAG or to any CRS vendor(s) for any flight during any month unless the carrier also provides the required flight data for the month to the Department as specified in Part 234 and in this Technical Directive.

IX. Reporting the Causes of Cancelled and Delayed Flights

1. There are four categories for cancellation:

A. Air Carrier
B. Extreme Weather
C. National Aviation System
D. Security

2. There are five categories for delayed flights:

E. Air Carrier
F. Extreme Weather
G. National Aviation System
H. Security
I. Late Arriving Aircraft

3. Causal data must be reported for cancelled and late arriving flights (flights that arrive at the destination airport 15 minutes or more after the scheduled arrival time. No causal data are required for flights that are considered on-time or for diverted flights.

4. For all late flights, you account for the cause and length of departure delays of 6 minutes or longer (with the exception of No. 5 below). Carriers may choose to report only the predominant departure delay but they must do it on a consistent basis. Also, carriers that report predominant cause of delay must abide by No. 8 below.

5. When there are multiple causes of delays that start at the same time, report the cause of delay having the longest duration.

6. Reported delay minutes must equal the arrival delay. When the arrival delay is greater than the departure delay, the difference is attributed to NAS.

7. When departure delay is greater than the arrival delay, report the arrival delay minutes. If there were multiple delay causes, prorate the time-savings to each cause of delay. Report in whole minutes and do not report a negative number for the length of delay.

8. Causal delay minutes assigned to late arriving aircraft can be equal to or less than but not more than the delay time of the previous flight operated with the same aircraft with one exception, i.e. a carrier swaps aircraft between routes to lessen delays.

(At 2 p.m., aircraft N0011 arrived on time and its next flight segment is scheduled to depart at 5 p.m. Aircraft N0012 was scheduled to arrive at 1 p.m. and is still en-route. The next scheduled flight with this aircraft is at 2:10 p.m. The air carrier swapped aircraft and the 2:10 p.m. flight departed at 2:30 p.m. The carrier reported a 20 minute delay for late arriving aircraft even though the previous flight with this aircraft arrived on-time.) The flight scheduled to depart at 2:10 p.m. would have departed even later if the air carrier had not swapped aircraft.

Causal Delays and Cancellations

The primary purpose for collecting causal data is to categorize delays and cancellations so that system problems can be identified and the appropriate parties can take corrective action.

Air Carrier Delays or Cancellations

Below is a list of examples of causes for delays and cancellations that we believe are within the control of the air carrier. This list should be used as a guide for the type of occurrences that should be reported as an air carrier delay and/or cancellation. It should not be considered a complete list, and we welcome comments on additions or deletions.

Air Carrier

Aircraft cleaning
Aircraft damage (except bird strikes, lightning/hail damage)
Airport curfew
Awaiting the arrival of connecting passengers or crew
Awaiting alcohol test
Awaiting gate space
Baggage loading
Cabin servicing
Cargo loading
Catering
Computer outage - carrier equipment
Crew legality (pilot or attendant rest)
Damage by hazardous goods
Engineering Inspection
Public Health, etc.
Flight paperwork
Fueling
Gate congestion
Government forms not properly completed - INS, FAA, Agriculture
Ground equipment out of service
Hot brakes restriction
Last minute passenger
Late mail from Post Office
Late crew
Lavatory servicing
Maintenance
Medical emergency
Out of service aircraft
Oversales
Positive passenger baggage match
Passenger services
Potable water servicing
Pre-flight check
Ramp congestion - blocked by another aircraft under carrier's control
Ramp service
Removal of unruly passenger
Revised weight sheet
Shortage of ramp equipment
Slow boarding or seating
Snow removal (when it is a carrier ramp service function)
Stowing carry-on baggage
Weight and balance delays

Weather

Below is a list of examples of causes for delays and cancellations that we believe are the result of weather. This list should be used as a guide for the type of occurrences that should be reported as an air carrier delay and/or cancellation. It should not be considered a complete list, and we welcome comments on additions or deletions.

Weather

Below minimum conditions
Clear ice inspection
Deicing aircraft
Earthquake
Extreme high or low temperatures
Hail Damage
Holding at gate for enroute weather
Hurricane
Lightning damage
Pre-planned cancellations that result from predicted weather
Snow Storm
Thunder Storm
Tornado

National Aviation System (NAS)

Below is a list of examples of causes for delays and cancellations that we believe are in the control of the FAA, airport operators or State/local officials. This list should be used as a guide for the type of occurrences that should be reported as an air carrier delay and/or cancellation. It should not be considered a complete list; and we welcome comments on additions or deletions.

National Aviation System (NAS)

Airport conditions
Airport construction
Air Traffic Control (ATC)
Awaiting ATC clearance while still at gate
Air Traffic Quota Flow Program - ATC
Closed Runways
Computer failure - ATC equipment
Equipment Outage - ATC
Gate hold - ATC
Ground delay program - ATC
Flow control program - FAA
Other disabled aircraft blocking runway
Ramp congestion - blocked by aircraft not under carriers control
Ramp Traffic - Air Traffic Control
Restricted aircraft movement on runways
Volume Delays

Security

Below is a list of examples of causes for delays and cancellations that we believe were the result of security measures outside the control of air carriers. This list should be used as a guide for the type of occurrences that should be reported as an air carrier delay and/or cancellation. It should not be considered a complete list; and we welcome comments on additions or deletions.

Security

Bomb threat
Inoperative screening equipment - TSA
Evacuation of terminal or concourse resulting from security breech
Re-boarding aircraft because of security breech
Sky Marshal caused delay
Weapon confiscation
Lines at screening area that exceed standard time (see X. Security Screening below)

Note: Delays caused by routine passenger screening should not be assigned to "Security" when the wait at screening areas are less than 30 minutes. Also, air carriers should ensure that delays and cancellations assigned to "Security" were not attributable to their own actions or caused by their own employees who fail to follow security procedures.

Late Arriving Aircraft

Late Arriving Aircraft means a previous flight with the same aircraft arrived late which caused the present flight to depart late. The minutes assigned to Late Arriving Aircraft can never be more than the delay time of the previous flight. When assigning a causal code for Late Arriving Aircraft, the carrier must consider the scheduled time between flights and the carriers allotted turn time. (Exception from the same aircraft rule is allowed when carrier substitutes an aircraft for a delayed aircraft in order to decrease the delay of upcoming flights).

Guidance for Calculating Delay Minutes Attributed to a Late Arriving Flight

Minutes attributed to a Late Arriving Flight = Arrival time of previous flight + Scheduled turn time Scheduled Departure time.

Examples:

  1. A Flight was 40 minutes late and arrived @ 2:15. There was a scheduled 20- minute turn-time and the next flight was schedule to depart at 1:55. (2:15 + 20 minutes 1:55 = A 40 minute delay may be attributed to a late arriving aircraft.)
  2. A flight was 60 minutes late and arrived @ 2:15. There was a scheduled 20-minute turn time and the next flight was scheduled to depart at 4:00. (2:15 + 20 minutes 4:00 = no allowable time for late arriving aircraft.

X. Security Screening

1. Long lines at the passenger screening area can cause carriers to delay flights, cause passenger inconvenience and anxiety, and create its own security risks. By the nature of the airline business, many screening areas have processing peaks and valleys, which generally result from a large number of flights being scheduled in a short period of time. While the Department is not mandating how air carriers schedule flights, it may be in the carriers self-interest to review scheduling practices to alleviate delays both inside the airport and on the tarmac.

2. While TSA is in control of passenger screening, the air carriers are responsible for managing the lines up to the screening lanes. Carriers can alleviate the need hold flights for passengers in screening queues by bringing those passengers to the front of the line. Managing the line becomes more problematical when the carrier has multiple flights scheduled to depart at the same time or multi carriers use the same screening areas.

3. Lines at some screening points amass early in the morning, after there were long lines at the carriers check-in-counter. The check-in lines quickly disperse when air carriers add service agents. These passengers gather at the screening queue. The problem could be lessened or avoided by air carriers rescheduling service-agents assignments to encourage a more even flow of passengers to the screening areas.

Procedural Statement

Some carriers use ACARS to track flight times, other carriers have their pilots record the required times.

Carriers have the option of tracking all causes of delays from the moment the delay occurs or only those causes that persist for 6 minutes or longer. Whichever method the carrier elects to use, the carrier must consistently apply the method in its monthly report.

Carriers have the option of reporting multiple causes of departure delays or the predominant cause of departure delays with two exceptions: (1) Causal delay minutes assigned to late arriving aircraft can be equal to or less than but never more than the delay time of the previous flight operated with the same aircraft; and (2) Carriers cannot use minutes assigned to NAS (because arrival delay was greater than departure delay) to disguise another delay cause. For example, a carrier had an 8-minute weather delay at departure and the flight arrived 23 minutes late. The correct reporting would be 8 minutes for weather and 15 minutes for NAS. Whichever method the carrier elects to use, the carrier must consistently apply the method in its monthly report.

Before submitting the first causal report, carriers must submit a dated Procedural Statement for On-Time Reporting advising BTS whether it: (1) uses ACARS to track times; (2) tracks causes of delay beginning with the first minute of delay or only delay causes of 6 minutes or longer; and (3) reports all causes of delays or only the predominant cause of delay. Carrier must email the Procedural Statement to ontime.support@dot.gov. If a carrier elects to change a reporting method, it must submit a revised Procedural Statement for On-Time Reporting before submitting its monthly 234 report.

Donald W. Bright

Donald W. Bright
Assistant Director
Airline Information