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Draft Advisory Circular 93-1, Reservations for Unscheduled Flights at High Density Traffic Airports

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Federal Aviation Administration, DOT.


Notice of draft advisory circular and request for comments.


This notice requests comments on Advisory Circular “Reservations for Unscheduled Flights at High Density Traffic Airports.” This advisory circular would harmonize and clarify procedures currently in the Aeronautical Information Manual and the Aeronautical Information Publication, update methods of obtaining reservations to include a new web-based application, discontinue use of telephone modem access, provide for an increase in the number of hours in advance of operation that reservations may be made, and reflect recent statutory changes affecting operations at Chicago O'Hare International Airport.


Comments must be received on or before June 24, 2002.


Comments should be mailed or delivered in duplicate to: U.S. Department of Transportation Dockets, Docket No. FAA-2002-XXXX, 400 Seventh Street, SW., Room Plaza 401, Washington, DC 20590. Comments may also be sent electronically to the following Internet address: http// Comments may be filed and/or examined in Room Plaza 401 between 10 a.m. and 5 p.m. weekdays except Federal holidays.

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Diane Crean, Manager, Terminal Operations/Procedures, ATP-120, 800 Independence Avenue, SW., Washington, DC 20591, telephone 202-267-3538, or facsimile 202-267-5305.

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Comments Invited

Interested persons are invited to comment by submitting such written data, views, or arguments, as they may desire. Communications should identify the docket number and be submitted in duplicate to the address specified above. Electronic filings should be made to the Docket via the Internet. The FAA will consider comments made on or before the closing date for comments before taking any action on the draft advisory circular.

The FAA will acknowledge receipt of a comment if the commentor includes a self-addressed, stamped postcard with the comment. The postcard should be marked “Comments to Docket No. FAA-2002-xxxx. When the FAA receives the comment, the postcard will be dated, time stamped, and returned to the commentor.


The FAA limits flights during certain hours at four high density traffic airports: John F. Kennedy International Airport (JFK), LaGuardia Airport (LGA), Chicago O'Hare International Airport (ORD), and Ronald Reagan Washington National Airport (DCA). (Although Newark International Airport is also designated as a high density traffic airport, the quotas for that airport have been suspended indefinitely.) Reservations for air carrier and commuter flights (also called slots) are allocated in accordance with Title 14 of the Code of Federal Regulations (CFR) Part 93, Subpart S, and are not allocated by the procedures described in this draft advisory circular. Reservation procedures for the “other” of category operations are currently in the Aeronautical Information Manual and other air traffic publications. The Airport Reservation Office (ARO), a function of the David J. Hurley Air Traffic Control System Command Center, allocates these reservations for unscheduled operations. Reservations are allocated primarily by the Computer Voice Reservation System (CVRS), which is currently available using a touch-tone telephone or a computer and telephone modem.

The FAA notes that certain general aviation and other unscheduled flights are currently limited at DCA. If future FAA actions regarding flights at DCA would require changes to the procedures described in this advisory circular, they will be addressed separately. Users should continue to check current NOTAMs for the latest information. Comments about the current flight limits at DCA are beyond the scope of this advisory circular.

This advisory circular announces several changes to current procedures and adds clarifying language. The major changes are discussed below.

The FAA proposes to change the lead-time during which a reservation for an unscheduled operation may be obtained from 48 hours with exceptions to 72 hours with no exceptions. Current procedures allow an operator to make a reservation no more than 48 hours in advance of the operation, with two exceptions. [The first exception is for weekends, which provides that reservations may be made on Thursday for Monday and on Friday for Tuesday. The second exception provides that an additional reservation beyond the 48-hour period may be made if the second reservation is for the same calendar day and is made during the same telephone call. The second exception was adopted to allow an operator to obtain roundtrip reservation availability beginning 48 hours in advance of the operation and to provide an opportunity to revise operational plans should the requested slot times not be available.] The FAA proposes the adoption of a straight 72-hour window to obtain a reservation and the elimination of the 48-hour window with the related exceptions. This new procedure permits an operator to make an arrival or departure reservation at a high density traffic airport (HDTA) beginning 72 hours in advance of the proposed hour of operation. The FAA believes that a 72-hour limit generally provides more advance time for obtaining reservations and planning operations accordingly. In addition, it will address an abuse of current procedures by some operators who obtain multiple reservations beginning at the earliest possible time for the express purpose of exceeding the 48-hour limits during one telephone call. One example of abuse is when an operator obtains a reservation for a 6 a.m. arrival 48 hours in advance and, in the same telephone transaction, makes a reservation for a 5 p.m. departure. The operator then makes additional reservations by second telephone call for a 6 a.m. departure and a 4 p.m. arrival. The operator ultimately conducts only flights arriving at 4 p.m. and departing at 5 p.m. using reservations that were both made more than 48 hours in advance. This results in inequitable opportunities for the operators who comply with the intent of Start Printed Page 38306the procedures. The FAA also has received numerous complaints from operators about certain peak hour reservations being fully allocated before the 48-hour period. This occurs due to the current exceptions to the 48-hour rule. The proposed 72-hour window addresses these issues and is expected to make the reservation process more open and equitable for all users. The FAA will continue to monitor operations and reservation allocation practices to determine whether additional actions are required to promote equitable access to reservations and the HDTA's for all unscheduled operators.

In Summer 2002, the FAA plans to enhance the current CVRS with a web-based interface that will allow users to make HDTA reservations using the Internet, and improve the response time of the touch-tone telephone interface. This replacement reservation system will be known as the Enhanced Computer Voice Reservation System (e-CVRS). At the same time e-CVRS is deployed, the current computer modem connection will be eliminated. The ability to make on-line reservations using the Internet will bring faster and easier reservation capability to many users. The computer modem interface will be discontinued primarily due to supportability and cost issues. The FAA does not plan to develop a replacement for the computer modem interface since it would largely duplicate the web interface.

The FAA is requesting comments on having users provide optional information on aircraft type and the next airport service point immediately prior to or following the operation at a high density airport. Fields for data input would be available using the Internet interface and the telephone interface of e-CVRS would be programmed to accept similar information. It would not be mandatory to provide this data to obtain a reservation. To the extent that it is available, this operational information would be combined with other data available to air traffic control and used for planning purposes. It may also be used to determine whether additional operations could be accommodated based on the expected demand.

Changes will also be made to incorporate recent statutory changes at certain high density traffic airports. On April 5, 2000, the Wendell H. Ford Aviation Investment and Reform Act for the 21st Century (AIR-21) was enacted. AIR-21 provides that (1) effective May 1, 2000, reservations are not required for flights conducting foreign air transportation at ORD; (2) effective July 1, 2001, the high density rule (HDR) will apply from 2:45 p.m. through 8:14 p.m. at ORD; (3) after July 1, 2002, the HDR will be eliminated at ORD; (4) effective January 1, 2007, the HDR will be eliminated at JFK and LGA. Therefore, beginning July 2, 2002, reservations will not be required at ORD and it will be eliminated from e-CVRS after that date.

The FAA will consider other comments beyond those specifically solicited above. However, changes that would require rulemaking are beyond the scope of this proposed advisory circular. In compliance with the Paperwork Reduction Act, a request for approval to collect the necessary information will be submitted to the Office of Management and Budget.

Draft Advisory Circular

1. Purpose

This circular provides information for obtaining instrument and visual flight rule (IFR/VFR) reservations for unscheduled operations at the High Density Traffic Airports (HDTA). The High Density Traffic Airports Rule (Title 14 of the Code of Federal Regulations (CFR), part 93, subpart K) classifies user groups as air carrier, commuter, and other operators. Reservations for regularly scheduled operations conducted by air carrier and commuter operators (also called slots) are allocated in accordance with 14 CFR part 93, subpart S—Allocation of Commuter and Air Carrier IFR Operations at High Density Traffic Airports. Reservations for all other operations are obtained through the Airport Reservation Office (ARO) using the procedures described in this circular.

2. Definitions

a. Reservation

An authorization received in compliance with 14 CFR part 93, subpart K, to operate to and/or from a designated HDTA. A reservation for DCA, JFK, or LGA is allocated on an hourly basis. However, at Chicago O'Hare (ORD) a reservation is allocated on a 30-minute basis. (Reservations at ORD will not be required after July 1, 2002.) A reservation authorizes an operation only within the approved time period unless the flight encounters an air traffic control (ATC) traffic delay. (Note: In addition to obtaining a reservation as described in this advisory circular, it is the separate responsibility of the user to comply with all other NOTAMs, security or other regulatory requirements to operate at an HDTA.)

b. Airport Reservation Office (ARO)

An operational unit of the FAA Air Traffic Control System Command Center that is responsible for administration of slot reservations for the “other” category of operations (nonscheduled flights) at HDTA's.

c. Unscheduled Operation

An operation other than one regulatory conducted by an air carrier or commuter between an HDTA and another service point. Certain types of air carrier and commuter operations are also considered for these purposes as unscheduled. These include irregular charter, hired aircraft service, ferry flights, and other nonpassenger flights.

d. Additional Reservation

An approved IFR and VFR reservation above the hourly IFR quota at an HDTA. Additional reservations are available for unscheduled operations only and are allocated in accordance with the procedures described in this circular.

e. Enhanced Computer Voice Reservation System (e-CVRS)

FAA operates the e-CVRS to make arrival and/or departure reservations at airports designated by 14 part 93 subpart K as HDTA. There is a touch-tone telephone interface and an Internet web interface for making reservations.

3. Discussion

a. The FAA designated John F. Kennedy International (JFK) LaGuardia (LGA), Chicaco O'Hare International (ORD), Ronald Reagan Washington National Airport (DCA), and Newark Intternational (EWR) Airports as high density traffic airports and has prescribed air traffic rules and requirements for operating aircraft to and from these airports (14 CFR Part 93, Subpart K). (The HDR at EWR has been suspended indefinitely.) Reservations for JFK are required from 3 p.m. through 7:59 p.m. local time. Reservations at ORD are required from 2:45 p.m. through 8:14 p.m. local time. Reservations for LGA and DCA are required from 6 a.m. through 11:59 p.m. local time. Helicopter operations are excluded from the requirement for a reservation. Reservations at ORD are not required for any aircraft providing foreign air transportation. Air-21 provides for slot restrictions to be removed at ORD after July 1, 2002, and at JFK and LGA on January 1, 2007.

b. The FAA has established an ARO to receive and process all IFR reservation requests for unscheduled operations at the HDTA's. This office monitors operation of the HDR and allocates reservations for the “other” Start Printed Page 38307category on a “first-come-first-served” basis determined by the time the request is received at the reservation office. Standby lists are not maintained. The ARO uses e-CVRS to make all reservations. Users may access the computer system using a touch-tone telephone or via the Internet. Requests for IFR reservations will be accepted beginning 72 hours prior to the proposed time of operation at the affected airport. For example, a request for an 11 a.m. reservation on a Thursday will be accepted beginning at 11 a.m. on the previous Monday.

c. A maximum of two transactions per telephone call/Internet session will be accepted.

d. The ARO will not provide scheduling according to planned departure/arrival time. Assignments will be made on an hourly or 30-minute basis, e.g., an approved reservation for 2000 UTC covers an operation any time from 2000 through 2059 at DCA, JFK, and LGA, and an approved reservation for 2145 at ORD covers an operation from 2145 through 2214.

e. A reservation does not ensure against traffic delays nor does it guarantee arrival and/or departure within such allotted hours. A reservation also is not an ATC clearance.

f. Users are advised to check current NOTAMs in effect for HDTA's. A reservation from e-CVRS does not constitute permission to operate at an HDTA if additional operational limits or procedures are required by NOTAM and/or regulation.

g. The filing of a request for an IFR reservation does not constitute the filing of an IFR flight plan as required by regulation. The IFR flight plan should be filed only after the reservation is obtained and should be filed through normal channels. The ARO does not accept or process flight plans.

4. IFR Reservations

a. For an IFR operation, an IFR reservation is required prior to takeoff for any operation to or from an HDTA. Users may obtain IFR reservations by (1) calling the ARO's interactive computer system via touch-tone telephone, or via the Internet; or (2) calling the ARO directly. The telephone number for the e-CVRS computer is 1-800-875-9694. Users would then select option number 1 from the menu to make a reservation using e-CVRS. This toll free number is valid for calls originating within the United States, Canada, and the Caribbean. Users outside those areas may access e-CVRS by calling the toll number of (703) 707-0568. The Internet Web address for accessing e-CVRS is​ecvrs.

User may contact the ARO at 703-904-4452 if they have a problem making a reservation using the automated interfaces, if they have a question concerning the HDTA regulations or procedures, of if they wish to make a telephone reservation from outside the United States, Canada, or the Caribbean. (Note: The inability to obtain a reservation because all the reservations have been allocated is not considered as having a problem making a reservation).

b. When filing a request for an IFR reservation, the pilot should be prepared to provide the following information:

(1) Name(s) of high density traffic airport(s) for which the pilot wishes reservation(s).

(2) Date(s) and hour(s) (UTC) of proposed operation(s).

(3) Aircraft call sign, flight identification, or tail number(s). Operators should ensure that for each reservation, the ARO has an accurate record of the call sign or aircraft identification number that will be used for communication with air traffic control. Operators using a 3-letter identifier and flight number for ATC communication should obtain a reservation using that same information. Operators using an aircraft tail number should obtain a reservation using the tail number. Note: The FAA monitors compliance with the requirement to obtain a reservation at the HDTA's by comparing ATC flight records with e-CVRS reservation data. Therefore, in order to ensure comparability of data, the operator should ensure that the call sign/tail number data is the same for both ATC and e-CVRS.

(4) Aircraft type identifier. This information is optional and is not required to obtain a reservation.

(5) Origin/Destination Airport immediately prior to or following the proposed operation at a high density traffic airport. This information is optional and is not required to obtain a reservation. The 3-letter identifier for the airport should be used.

c. Should the requested time not be available, the user will be offered the closest time before and after the requested time. If an alternate time is accepted, this will be considered an allocated reservation.

d. Users are encouraged to advise the ARO whenever a change is needed to a reservation. Changes should be made to e-CVRS reservations by using the telephone interface, the Internet web interface, or by calling the ARO.

e. A reservation should be canceled when a user knows that it will not be used. Cancellations should be made through e-CVRS as soon as practical using the telephone interface, the Internet web interface, or by calling the ARO. Early cancellation of reservation will provide opportunities for other operators to use the limited number of airport reservations.

f. The following information is needed to change or cancel a reservation:

(1) Aircraft 3-letter identifier and flight number or tail number, depending on what information was provided for the original reservation.

(2) Airport for which the reservation was made.

(3) Date and Time (UTC) of reservation.

(4) Reservation number.

5. Additional IFR Reservations

a. If ATC weather and capacity conditions are favorable and significant delay is not likely at an HDTA, the ARO may coordinate with the appropriate ATC facility to determine if additional IFR reservations may be accommodated at the HDTA for a specific time period, (See 14 CFR 93.129.) Generally, availability of additional reservations will not be determined more than 8 hours in advance. If available, additional IFR reservations will be granted on a first-come-first-serve basis using the procedures described in section 4 of this advisory circular. Reservations for IFR operations are not granted by the local ATC facility.

b. An operator who has been unable to obtain a reservation at the beginning of the 72-hour window may find he or she is able to obtain a reservation on the scheduled day of operation when additional reservations may be authorized.

c. ATC will accommodate declared emergency situations without regard to slot reservations.

6. Visual Flight Rules (VFR) Reservations

a. The operator of an unscheduled VFR operation may take off or land an aircraft under VFR at an HDTA if a departure or arrival clearance is obtained from the FAA ATC facility serving the HDTA.

b. Under 14 CFR 93.129, a VFR operation is an additional operation beyond the hourly and half-hourly quotas. VFR additional operations may be granted by ATC if they can be accommodated without significant delay to operations already allocated. In addition, the reported ceiling at the HDTA must be at least 1,000 feet and the reported ground visibility at least 3 miles.Start Printed Page 38308

c. Each HDTA lies within Class B airspace. A clearance from ATC to enter the airspace or depart the airport under VFR constitutes an approval for a VFR additional reservation. No additional reservation under this section is required for VFR operations. Operators who have obtained a reservation from e-CVRS for a VFR operation are encouraged to cancel those reservations at the earliest opportunity so that they may be available for IFR operations.

d. Any time an HDTA is not authorizing VFR operations, a NOTAM to that effect will be issued by the controlling ATC facility and a recording placed on the Automated Terminal Information Service.

7. Making HDTA Reservations Using e-CVRS

a. Telephone users. When using a touch-tone telephone to make a reservation, you are prompted for input of information about what you wish to do. All input is accomplished using the keypad on the telephone. One issue with a touch-tone telephone entry is that most keys have a letter and number associated with them. When the system asks for a date or time, it is expecting an input of numbers. A problem arises when entering a tail number, or 3-letter identifier. The system does not detect if you are entering a letter (alpha character) or a number. Therefore, when entering an aircraft identifier and flight number or aircraft registration/tail number two keys are used to represent each letter or number. When entering a number, precede the number you wish by the number 0 (zero) i.e., 01, 02, 03, 04, * * * If you wish to enter a letter, first press the key on which the letter appears and then pass 1, 2, or 3, depending upon whether the letter you desire is the first, second, or third letter on that key. For example to enter the letter “N” first press the “6” key because “N” is on that key, then press the “2” key because the letter “N” is the second letter on the “6” key. Since there are no keys for the letters “Q” and “Z,” e-CVRS pretends they are on the number “1” key. Therefore, to enter the letter “Q,” press 11, and to enter the letter “Z,” press 12.


Users are reminded to enter the “N” character with their tail numbers (see Table 1). Operators using a 3-letter identifier and flight number to communicate with ATC facilities should enter that call sign when making their reservation.

Table 1.—Codes for Call Sign/Tail Number Input

Codes for Call Sign/Tail Number Input Only

b. Additional helpful key entries: (See Table 2).

Table 2.—Helpful Key Entries

# After entering a call sign/tail number, depressing the “pound key” (#) twice will indicate the end of the tail number.
*2 Will take the user back to the start of the process.
*3 Will repeat the call sign/tail number used in a previous reservation.
*5 Will repeat the previous question.
*8 Tutorial Mode: In the tutorial mode each prompt for input includes a more detailed description of what is expected as input. *8 is a toggle on/off switch. If you are in tutorial mode and enter *8, you will return to the normal mode.
*0 Expert Mode: In the expert mode each prompt for input is brief with little or no explanation. Expert mode is also on/off toggle.

c. Internet Web Based Interface. The e-CVRS reservation system includes a Web-based interface. The Internet option is intended to provide a fast, user-friendly environment for making slot reservations. The Internet address is​ecvrs. The web-based interface incorporates the current CVRS telephone features and adds new features. In addition to the airport, date, time, and tail number/call sign information, you will be asked to enter the aircraft type and the arrival/departure airport immediately preceding or following your operation at an HDTA. If you are making an arrival reservation at an HDTA, you will be asked to provide the 3-letter identifier for your departure airport. Conversely, if you are making a departure reservation, you will now be asked for your destination airport. This information is optional and is not required to obtain a reservation. This information may be added or edited using e-CVRS after the reservation is initially obtained.

All users of e-CVRS must complete a one-time registration form containing the following information: full name; e-mail address; a personal password; password confirmation; and company affiliation (optional). Your e-mail and password are required each time you login to use e-CVRS. Instructions are provided on each page to guide you through the reservation process. If you need help at any time, you can access page-specific help by clicking the question mark “?” located in the upper right corner of the page.

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Issued in Washington, DC, on May 28, 2002.

Michael A. Cirillo,

Program Director for Air Traffic Planning and Procedures.

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[FR Doc. 02-13820 Filed 5-31-02; 8:45 am]