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Note: EDTO means Extended diversion time operation.
(a) Except as provided in rule 121.165(d), a holder of an air operator certificate must not operate an aeroplane on an EDTO unless—
(1) the certificate holder is authorised under this Subpart to conduct an EDTO; and
(2) the certificate holder’s operations specifications required by rule 119.15—
(i) permits the intended EDTO; and
(ii) authorises the use of the airframe and engine combination for the EDTO; and
(3) procedures for meeting the requirements of this Subpart for EDTO are detailed in the certificate holder’s exposition required by rule 119.81.
(b) The Director may, on application in writing for an EDTO by a holder of an air operator certificate, authorise air operations beyond the time limits of the most time-limited system for an aeroplane as specified in the flight manual if satisfied on the evidence of a safety risk assessment provided by the operator covering the following:
(1) the capabilities of the operator in conducting EDTOs; and
(2) the overall reliability of the aeroplane to be operated under the EDTO; and
(3) the reliability of each time-limited system of the aeroplane to be operated under the EDTO; and
(4) information from the aeroplane manufacturer relevant to an EDTO; and
(5) any specific mitigation measures to be taken by the certificate holder.
(a) A holder of an air operator certificate may apply in writing to the Director for an EDTO authorisation to operate an aeroplane with 2 turbine powered engines on an EDTO up to 180 minutes maximum diversion time.
(b) A holder of an air operator certificate applying for an EDTO authorisation under paragraph (a) must provide the Director with the following information at least 90 days, or a lesser period acceptable to the Director, before the proposed commencement of the EDTO:
(1) details of the particular airframe and engine combination of each aeroplane to be operated under the EDTO authorisation:
(2) details, and evidence of the type design approval and the operating limitation of the airframe and engine combination, proposed under paragraph (1), for operating the aeroplane on an EDTO of more than 60 minutes flight time from an adequate aerodrome:
(3) details of the CMP for the airframe and engine combination proposed under paragraph (1):
(4) the maximum diversion time proposed for the EDTO which must be not more than 180 minutes:
(5) the minimum altitudes applicable to the routes to be flown on the EDTO including any diversionary routes:
(6) details of the fuel policy required to meet the requirements of rule 121.975:
(7) details of the maintenance programme required to meet the requirements of rule 121.407:
(8) details of the training programme required under Subpart I and applicable to the EDTO and the maximum diversion time proposed under paragraph (4):
(9) details of the MEL relevant to the maximum diversion time proposed under paragraph (4):
(10) evidence that the aeroplane conforms to the fire detection and suppression limitations for cargo and baggage compartments prescribed in paragraph D.5(a)(2) of Appendix D to Part 26, or an equivalent standard acceptable to the Director:
(11) evidence that time limited system capability for the aeroplane plus a 15 minute allowance for holding, approach, and landing is not less than the maximum diversion time proposed under paragraph (4):
(12) details of every EDTO alternate aerodrome that is required for the routes to be flown and the maximum diversion time proposed under paragraph (4):
(13) details—
(i) to confirm that every EDTO alternate aerodrome that is detailed under paragraph (12) has facilities to ensure the safety of a full complement of passengers and crew members:
(ii) of the recovery plan for diversion to an EDTO alternate aerodrome that ensures the safety of a full complement of passengers and crew members at the aerodrome or in the immediate area until they are transported to another place that can provide for their safety:
(14) details of the point of no return for the aeroplane (if known).
(a) The Director may amend the operations specifications required by rule 119.15 to authorise a holder of an air operator certificate to conduct air operations using an aeroplane with 2 turbine powered engines on EDTO up to 180 minutes maximum diversion time if the Director is satisfied that—
(1) the airframe and engine combination is approved by the State of Design to operate to the maximum diversion time requested by the certificate holder; and
(2) every applicable requirement of this Part is met.
(b) Despite paragraph (a)(1), the Director may amend the operations specifications under paragraph (a) to authorise a holder of an air operator certificate to use an aeroplane on an EDTO to not more than 75 minutes maximum diversion time if the aeroplane has 2 turbojet or turbofan powered engines and the Director considers that the proposed airframe/engine combination, although not approved by the State of Design to operate more than 60 minutes flight time (calculated at a one engine inoperative cruise speed in still air and ISA conditions) from an adequate aerodrome, is suitable for the intended EDTO.
(a) A holder of an air operator certificate who is authorised under rule 121.955 to operate an aeroplane with 2 turbine powered engines on an EDTO up to 180 minutes maximum diversion time may apply in writing to the Director for an EDTO authorisation to operate an aeroplane with 2 turbine powered engines on an EDTO up to 240 minutes maximum diversion time.
(b) A holder of an air operator certificate applying for an EDTO authorisation under paragraph (a) must provide the Director with—
(1) the information required by rule 121.953(b) but applicable to the maximum diversion time proposed for EDTO which may not be more than 240 minutes; and
(2) evidence that the aeroplane is equipped with a communications system that is—
(i) additional to the communications equipment required by rules 91.519 and 121.353; and
(ii) capable of providing direct communication of landline voice quality between the flight crew members and an appropriate ATS unit, and the flight crew members and the air operator.
The Director may amend the operations specifications required by rule 119.15 to authorise a holder of an air operator certificate to conduct air operations using an aeroplane with 2 turbine powered engines on EDTO up to 240 minutes maximum diversion time if the Director is satisfied that—
(1) the certificate holder has a demonstrated capability conducting EDTOs under a 180 minute EDTO authorisation issued under rule 121.955; and
(2) the airframe and engine combination of the aeroplane to be used for the EDTO is approved by the State of Design to operate to the maximum diversion time requested by the certificate holder; and
(3) the requirements of rule 121.957(b) are met.
(a) A holder of an air operator certificate may apply in writing to the Director for an EDTO authorisation to operate an aeroplane with 2 turbine powered engines on an EDTO more than 240 minutes maximum diversion time if, immediately before applying, the certificate holder has been—
(1) conducting EDTO in accordance with an EDTO authorisation issued by the Director under rule 121.955 or 121.959 for at least 24 consecutive months; and
(2) conducting EDTO of more than 180 minutes with the aeroplane airframe/engine combination to be used in accordance with an EDTO authorisation issued by the Director under rule 121.959 for at least 12 consecutive months.
(b) A holder of an air operator certificate applying for an EDTO authorisation under paragraph (a) must provide the Director with—
(1) the information required by rule 121.953(b) but applicable to the maximum diversion time proposed for EDTO; and
(2) evidence that the aeroplane is equipped with the communications system required by rule 121.957(b)(2).
The Director may amend the operations specifications required by rule 119.15 to authorise a holder of an air operator certificate to conduct air operations using an aeroplane with 2 turbine powered engines on EDTO more than 240 minutes maximum diversion time if the Director is satisfied that—
(1) the certificate holder has a demonstrated capability conducting EDTOs as required by rule 121.961(a); and
(2) the airframe and engine combination of the aeroplane to be used for the EDTO is approved by the State of Design to operate to the maximum diversion time requested by the certificate holder; and
(3) the requirements of rule 121.961(b) are met.
(a) A holder of an air operator certificate may apply in writing to the Director for an EDTO authorisation to operate an aeroplane with more than 2 turbine powered engines on a route that requires the aeroplane to be more than 180 minutes flight time (calculated at a one-engine inoperative cruise speed in still air and ISA conditions) from an adequate aerodrome.
(b) Subject to rule 121.967(b), a holder of an air operator certificate applying for an EDTO authorisation under paragraph (a) must provide the Director with—
(1) the information required by rule 121.953(b) but applicable to the airframe and engine combination of the aeroplane to be used for the EDTO and to the maximum diversion time proposed; and
(2) evidence that the aeroplane is equipped with the communications system required by rule 121.957(b)(2).
(a) Subject to paragraph (b), the Director may amend the operations specifications required by rule 119.15 to authorise a holder of an air operator certificate to conduct air operations using an aeroplane with more than 2 turbine powered engines on EDTO more than 180 minutes maximum diversion time if the Director is satisfied that:
(1) the requirements of rule 121.965(b) are met; and
(2) the airframe and engine combination of the aeroplane to be used for the EDTO is approved by the State of Design to operate to the maximum diversion time requested by the certificate holder.
(b) The requirements in rule 121.953(b)(3) regarding CMP details of the airframe and engine combination, and in paragraph (a)(2) regarding EDTO approval by the State of Design for the airframe and engine combination do not apply to an aeroplane with more than 2 turbine powered engines that was manufactured before 1 November 2018 and is used for EDTO more than 180 minutes maximum diversion time if the holder of the air operator certificate provides the Director with evidence that the airframe and engine combination of the aeroplane is suitable for the aeroplane to operate on EDTO to the maximum diversion time requested by the certificate holder.
(a) A holder of an air operator certificate who is authorised in accordance with this Subpart to conduct EDTO must not allow an aeroplane to be dispatched on an EDTO unless—
(1) the communications systems required by rules 91.519 and 121.353 are operable; and
(2) subject to paragraph (b), every aerodrome that is required for the operation, including take-off and take-off alternate, destination and destination alternate, and en-route EDTO alternate aerodromes, is listed in the dispatch release provided to the pilotin- command; and
(3) for EDTO up to and including 180 minutes maximum diversion time, the flight time (at a one engine inoperative cruise speed in still air and ISA conditions) to the nearest en-route EDTO alternate aerodrome listed in the dispatch release does not exceed the time specified in the aeroplane flight manual for the capability of the most critical time limited system (including the most limiting fire suppression time for the cargo and baggage compartments) minus 15 minutes.
(b) Except as provided in paragraph (c), an aerodrome may not be listed in the dispatch release under paragraph (a)(2) as an en-route EDTO alternate aerodrome unless—
(1) the aerodrome is an EDTO alternate aerodrome and is listed in the certificate holder’s operations specifications as required by rule 119.15(d)(3); and
(2) at least 1 suitable instrument approach procedure, published in the AIP of the State concerned, will be available at the aerodrome during the period from the earliest possible time of landing to the latest possible time of landing at the aerodrome; and
(3) the latest available meteorological forecast for the aerodrome indicates that, during the period from the earliest possible time of landing to the latest possible time of landing at the aerodrome—
(i) the meteorological conditions at the aerodrome will be at or above the relevant aerodrome planning minima for an en-route EDTO alternate aerodrome prescribed in rule 121.977; and
(ii) the crosswind component, including gusts, for the landing runway expected to be used is not more than the maximum permitted crosswind in the aeroplane flight manual.
(c) An aerodrome may be listed in a dispatch release as an en-route EDTO alternate aerodrome and the aeroplane dispatched on an EDTO if the meteorological forecast required by paragraph (b)(3) is not available at the time of dispatch but the pilot-in-command must not proceed beyond the point of sole reliance on the aerodrome unless the pilot-in-command receives a valid meteorological forecast for the aerodrome prior to reaching that point of sole reliance and the requirements of paragraph (b)(3) are met.
(d) For the purpose of paragraph (b)(3), forecast probabilities of less than 40% may be disregarded, but TEMPO conditions, when forecasted, must be taken into account when calculating fuel requirements.
A holder of an air operator certificate who is authorised in accordance with this Subpart to conduct an EDTO must not allow an aeroplane to be dispatched on an EDTO that requires the aeroplane to be more than 180 minutes flight time from an en-route EDTO alternate aerodrome listed in the dispatch release unless:
(1) the requirements of rule 121.969 are complied with; and
(2) the following systems on the aeroplane are operational:
(i) fuel quantity indicating systems:
(ii) the APU, including the electrical and pneumatic supplies operating at the APU’s designed capability, if an operational APU is required for the aeroplane to be approved for EDTO:
(iii) auto throttle/auto thrust systems:
(iv) the communications system required by rule 121.957(b)(2); and
(3) the aeroplane has a one-engine-inoperative auto-land capability if flight planning is predicated on that capability; and
(4) the flight time (at the all engines operating cruise speed, correcting for wind and temperature) to the nearest en-route EDTO alternate aerodrome listed in the dispatch release does not exceed the time specified in the aeroplane flight manual for the most limiting capability of the cargo and baggage compartment fire suppression system minus 15 minutes at any stage of the flight; and
(5) the flight time (at a one engine inoperative cruise speed, correcting for wind and temperature) to the nearest en-route EDTO alternate aerodrome listed in the dispatch release does not exceed the time specified in the aeroplane flight manual for the capability of the most critical time limited system (not including cargo and baggage compartment fire suppression systems) minus 15 minutes.
(a) A holder of an air operator certificate who is authorised in accordance with this Subpart to conduct an EDTO must ensure that the pilot-incommand of an aeroplane conducting an EDTO under the authority of the certificate is notified of any significant change in the conditions at any en-route EDTO alternate aerodrome listed in the dispatch release for the flight—
(1) before the aeroplane proceeds beyond the EDTO entry point: and
(2) after the aeroplane has proceeded beyond the EDTO entry point.
(b) If the pilot-in-command of an aeroplane performing an EDTO is notified of a significant change in the conditions at an en-route EDTO alternate aerodrome listed in the dispatch release before the aeroplane proceeds beyond the EDTO entry point, the pilot-in-command must ensure that—
(1) the change in the conditions at the aerodrome are evaluated; and
(2) if any change in the conditions at the aerodrome may preclude a safe approach and landing at the aerodrome during the possible period of use referred to in paragraph (c)(1), an alternative and suitable en-route EDTO alternate aerodrome is selected where a safe approach and landing can be made.
(c) The pilot-in-command of an aeroplane performing an EDTO must not proceed beyond the EDTO entry point unless, for each en-route EDTO alternate aerodrome listed in the dispatch release for the flight or selected under paragraph (b)(2),—
(1) the meteorological forecast for the aerodrome indicates that the meteorological conditions will be at or above the published aerodrome landing minima for the expected approach during the period of possible use; and
(2) the aerodrome qualifies as an en-route EDTO alternate aerodrome.
(d) The pilot-in-command of an aeroplane performing an EDTO must ensure that the aeroplane complies with the in-flight operational requirements of the CMP standards for an EDTO.
(e) If the pilot-in-command of an aeroplane performing an EDTO is advised of a significant change in the conditions at an en-route EDTO alternate aerodrome listed in the dispatch release after the aeroplane has proceeded beyond the EDTO entry point, and the change in conditions makes the aerodrome no longer usable as an en-route EDTO alternate aerodrome, the pilot-in-command may only continue the flight if the pilotin- command is satisfied that doing so would be safer than an alternative course of action.
(f) For the purpose of paragraphs (a), (b) and (e), a significant change in the conditions at an en-route EDTO alternate aerodrome includes:
(1) a change in the meteorological aerodrome forecast for the aerodrome that indicates that the weather conditions at the time of expected use will be below the landing minima for the aerodrome:
(2) a change in the condition of the aerodrome or services at the aerodrome that makes the aerodrome unsuitable as an EDTO alternate aerodrome.
(a) A holder of an air operator certificate who is authorised under this Subpart to conduct an EDTO must not allow an aeroplane to be dispatched on an EDTO unless, in addition to the requirements of the certificate holder’s fuel policy required by rule 121.75, the following requirements are met:
(1) the aeroplane must carry the greater of the following—
(i) sufficient fuel to fly to an en-route EDTO alternate aerodrome listed in the dispatch release assuming a rapid decompression at the most critical point followed by a descent to a safe altitude in compliance with rule 91.423, and rule 91.209 relating to the use of oxygen equipment, or
(ii) sufficient fuel to fly to an en-route EDTO alternate aerodrome listed in the dispatch release at the approved one engine inoperative cruise speed assuming a rapid decompression and a simultaneous engine failure at the most critical point followed by a descent to a safe altitude in compliance with rule 91.423 and the oxygen requirements of rule 91.209; or
(iii) sufficient fuel to fly to an en-route EDTO alternate aerodrome listed in the dispatch release at the approved one engine inoperative cruise speed assuming an engine failure at the most critical point followed by a descent to the one engine inoperative cruise altitude; or
(iv) EDTO critical fuel for the aeroplane;
(2) the aeroplane, upon reaching the en-route EDTO alternate aerodrome must have sufficient fuel to hold for 15 minutes at 1,500 feet above the aerodrome elevation and then to conduct an instrument approach procedure and land.
(b) For the purposes of calculating the fuel required by paragraph (a), the certificate holder must take the following matters into account:
(1) if the certificate holder is using a wind forecast model acceptable to the Director, a 5% wind speed factor (i.e. as an increment to a headwind or as a decrement to a tailwind) must be added onto the actual or forecast wind used to calculate the fuel required by paragraph (a)(1) to account for errors in wind forecasting:
(2) if the certificate holder is not using a wind forecast model acceptable to the Director, the aeroplane must carry an additional 5% of the fuel required by paragraph (a)(1) to allow for errors in wind forecasting:
(3) if icing conditions are forecast for the planned EDTO, the fuel required by paragraph (a)(1) must compensate for the greater of—
(i) the effect of airframe icing during 10% of the time during which icing is forecast taking into account the fuel that would be used by the use of engine and wing anti-ice during the same period; or
(ii) the fuel used by use of engine anti-ice systems, and if appropriate the use of wing anti-ice systems for the entire time during which icing is forecast:
(4) the fuel required by paragraph (a)(1) must include—
(i) additional fuel, calculated in accordance with the certificate holder’s performance deterioration allowance monitoring programme to compensate for any increase in the aeroplane’s fuel consumption; or
(ii) if a performance deterioration allowance monitoring programme is not used for the aeroplane’s fuel consumption, an additional 5% of the fuel required by paragraph (a)(1) to account for the deterioration in cruise fuel burn performance:
(5) if an APU is a required power source for operating the aeroplane on an EDTO, the fuel required by paragraph (a)(1) must include the APU fuel consumption during every phase of flight when the APU may be used:
(6) the fuel required by paragraph (a)(1) must include any additional fuel consumption caused by the use of an MEL or configuration deviation list item for any applicable phases of flight.
Except as provided in rule 121.979, the applicable minima for an aerodrome to be listed as an en-route EDTO alternate aerodrome under rule 121.969 are specified in the following table:
| Facilities available at EDTO en-route alternate | Ceiling | Visibility |
|---|---|---|
| Two or More Separate Precision Approach Procedure Equipped Runways (Note: A single runway with reciprocal precision approach procedures does not meet this requirement) |
Cloud-base of 400 feet or a cloud-base of 200 feet above the lowest aerodrome landing minimum; whichever is higher. | A visibility of 1500 metres or a visibility of 800 metres more than the lowest aerodrome landing minimum; whichever is greater. |
| A Single Precision Approach Procedure | Cloud-base of 600 feet or a cloud-base of 400 feet above the lowest aerodrome landing minimum; whichever is higher. | A visibility of 3000 metres or a visibility of 1500 metres more than the lowest aerodrome landing minimum; whichever is greater. |
| Non-precision Approach Procedure | Cloud-base of 800 feet or a cloud-base of 400 feet above the lowest aerodrome landing minimum; whichever is higher. | A visibility of 4000 metres or a visibility of 1500 metres more than the lowest aerodrome landing minimum; whichever is greater. |
Despite rule 121.977, at an aerodrome where a Category II or Category III precision approach procedure is permitted, planning minima lower than the en-route EDTO alternate aerodrome planning minima stated in rule 121.977 may be used if the precision approach is performed in accordance with the approved precision approach procedure manual required by rule 91.417.
For the purpose of this Part, a holder of an air operator certificate who, immediately before 1 November 2010, was authorised in the certificate holder’s operations specifications to conduct extended-range twin-engine operations (ETOPS) using an aeroplane with 2 turbine powered engines is deemed to be authorised in accordance with Subpart N to conduct an EDTO using the same aeroplane airframe/engine combinations and on the same routes and to the same maximum diversion time as was authorised for ETOPS in the certificate holder’s operations specifications.
