A selection of Frequently Asked Questions (FAQs) on CORSIA and related responses is available for download here.
In addition to the fundamental importance that States attribute to the protection of environment and in particular the importance of taking action to tackle climate change...read more
| 1. | General questions about a market-based measure (MBM) and CORSIA | |
| 1.1 | What is a market-based measure (MBM)? | |
| 1.2 | What is the contribution of aviation to global greenhouse gas emissions? | |
| 1.3 | Why does the Paris Agreement not include international aviation emissions? | |
| 1.4 | Why did ICAO decide to develop a global MBM scheme for international aviation? | |
| 1.5 | What ICAO process was followed to develop CORSIA? | |
| 1.6 | What is CORSIA and how does it work, in general? | |
| 2. | Questions about CORSIA’s key design elements | |
| Key design element 1: Phased implementation of CORSIA | ||
| 2.1 | What is the rationale for the phased implementation of CORSIA? | |
| 2.2 | What are the different phases? | |
| 2.3 | What is the difference between the pilot phase (from 2021 through 2023) and the first phase (from 2024 through 2026)? | |
| 2.4 | Which criteria determine the participation or exemption of States from CORSIA offsetting in its second phase from 2027 to 2035? | |
| 2.5 | What is a “RTK”? | |
| 2.6 | How are RTK shares calculated? | |
| Key design element 2: Route-based approach of CORSIA | ||
| 2.7 | What is the route-based approach of CORSIA? | |
| 2.8 | What does “participation of States to CORSIA offsetting” mean for the route-based approach? | |
| 2.9 | Can the characterisation of a route as “covered” or “not covered” by the CORSIA offsetting change over time? | |
| 2.10 | Do States and aeroplane operators that do not participate in the CORSIA offsetting have any requirements under CORSIA? | |
| 2.11 | Can an aeroplane operator have offsetting requirements, even if its State of registration does not participate in CORSIA offsetting? | |
| 2.12 | What would happen to the CORSIA emissions coverage if an operator of a non-participating State flies on the routes between participating States (e.g. fifth-freedom traffic right)? | |
| 2.13 | What would happen to the CORSIA emissions coverage if a State without an operator undertaking international flights decides to participate in the CORSIA offsetting? | |
| Key design element 3: CORSIA offsetting requirements and eligible emissions units | ||
| 2.14 | What is offsetting and how does it work, in general? | |
| 2.15 | How are an aeroplane operator’s offsetting requirements calculated? | |
| 2.16 | What are CORSIA’s compliance periods? | |
| 2.17 | What are CORSIA’s baseline emissions? | |
| 2.18 | What is the difference between the Sector’s Growth Factor used by the formula under CORSIA and the generally-used term “emissions growth rate”? | |
| 2.19 | How are CORSIA Eligible Fuels accounted for in the calculation of offsetting requirements? | |
| 2.20 | Can an aeroplane operator address its offsetting requirements accrued in CORSIA both through CORSIA Eligible Emissions Units and CORSIA Eligible Fuels? | |
| 2.21 | Can an aeroplane operator’s CO2 offsetting requirements be negative? | |
| 2.22 | Will an aeroplane operator, which reduces its emissions compared to the baseline, have any offsetting requirements? | |
| Key design element 4: Exemptions and new entrants | ||
| 2.23 | Does the CORSIA include provisions to exempt very low international aviation activities? | |
| 2.24 | How will the CORSIA apply to new operators that will initiate activities after the entry into force of the scheme (a so-called “new entrant”)? | |
| 2.25 | Will a new entrant operator affect the CORSIA baseline? | |
| 2.26 | If an aeroplane operator, which (in the past) had domestic operations only, establishes international routes, will it be considered a new entrant? | |
| Key design element 5: Review process | ||
| 2.27 | Does the CORSIA include provisions to review its implementation and to make adjustments if needed? | |
| 2.28 | What was the methodology followed to undertake the 2022 CORSIA periodic review? | |
| 2.29 | What was the outcome of the 2022 CORSIA periodic review? | |
| 2.30 | What will be the methodology applied for future CORSIA periodic reviews? | |
| 3. | Questions about Annex 16, Volume IV - CORSIA | |
| General questions related to Annex 16, Volume IV | ||
| 3.1 | What are the differences between: Annex 16, Volume IV; Environmental Technical Manual, Volume IV; and CORSIA Implementation Elements? | |
| 3.2 | What ICAO process was followed to develop Annex 16, Volume IV? | |
| Administrative aspects | ||
| 3.3 | What is the definition of international flight for CORSIA purposes? | |
| 3.4 | What guidance should be followed to determine whether a flight is international or domestic? | |
| 3.5 | Does CORSIA apply to international flights to/from non-ICAO States? | |
| 3.6 | What is the definition of an "aeroplane" in CORSIA? How does this definition differ from the definition of an “aircraft”? | |
| 3.7 | What is the definition of “an aerodrome” in CORSIA? | |
| 3.8 | How are diverted flights handled in CORSIA? | |
| 3.9 | What does a “State pair” mean? Is it uni- or bidirectional? | |
| 3.10 | Who will ensure that aeroplane operators comply with the requirements of Annex 16, Volume IV? | |
| 3.11 | How is an international flight being attributed to a single aeroplane operator? | |
| 3.12 | How is an aeroplane operator being attributed to a single State? | |
| 3.13 | Can an aeroplane operator delegate its administrative requirements? | |
| 3.14 | Can an aeroplane operator report together with one or more of its subsidiaries? | |
| 3.15 | Who is responsible for reporting emissions from flights operated with leased aeroplanes? | |
| 3.16 | Can a State delegate its administration processes under the CORSIA to another State? | |
| 3.17 | How long does a State and an aeroplane operator need to keep CORSIA-related records? What is included in those records? | |
| Monitoring, reporting and verification (MRV) | ||
| 3.18 | What are the components of the CORSIA MRV system? | |
| 3.19 | What is the applicability of the CORSIA MRV requirements? Are they any exemptions? | |
| 3.20 | In view of the decisions made by the ICAO Council in order to safeguard against inappropriate economic burden on aeroplane operators due to the COVID-19 pandemic, did aeroplane operators have to undertake the monitoring, reporting and verification of CO2 emissions from international flights operated in 2020? | |
| 3.21 | Can an aeroplane operator with emissions of less than 10 000 tonnes of CO2 per year be included in CORSIA? | |
| 3.22 | What are the actions for an aeroplane operator, who has been covered by CORSIA, but now drops below the 10 000 tonnes of CO2 threshold? | |
| 3.23 | How to address aeroplane operators with annual CO2 emissions close to the 10 000 tonnes threshold? | |
| 3.24 | Are aeroplane manufacturers or airports subject to any requirements under Annex 16, Volume IV? | |
| 3.25 | Is a re-positioning flight before or after an exempted humanitarian, medical or firefighting flight exempt? | |
| 3.26 | Are helicopter operations covered by the CORSIA MRV system? | |
| 3.27 | Are international flights by police, military, customs or State aircraft within the scope of applicability of the CORSIA MRV system? | |
| 3.28 | How can humanitarian, medical, firefighting, police, military, customs and State aircraft flights be identified? | |
| 3.29 | Are Search and Rescue (SAR) flights exempted from CORSIA? | |
| 3.30 | Are repatriation flights operated under specific situations (e.g. COVID-19 pandemic) identified as humanitarian flights in the context of CORSIA implementation? | |
| 3.31 | How are diversions handled in CORSIA? | |
| Emissions Monitoring Plan | ||
| 3.32 | What is an Emissions Monitoring Plan and why is it needed? | |
| 3.33 | What are the contents of an Emissions Monitoring Plan? | |
| 3.34 | Is there a standardised template for an Emissions Monitoring Plan? | |
| 3.35 | When should an aeroplane operator submit an Emissions Monitoring Plan to the State? | |
| 3.36 | When will the Emissions Monitoring Plan be approved by the State? | |
| 3.37 | Does the third-party verification body need to review the Emission Monitoring Plan prior to its review and approval by the State? | |
| 3.38 | Does the Emissions Monitoring Plan have to be submitted annually? | |
| 3.39 | What happens if there are changes to the information contained in an Emissions Monitoring Plan? | |
| 3.40 | How should non-material changes to an Emissions Monitoring Plan be communicated to the State? | |
| Monitoring | ||
| 3.41 | How does an aeroplane operator monitor its fuel use and CO2 emissions? | |
| 3.42 | Who approves the monitoring method for an aeroplane operator? | |
| 3.43 | Who are eligible to use the ICAO CORSIA CO2 Estimation and Reporting Tool (CERT)? | |
| 3.44 | Where can one access the ICAO CORSIA CERT? | |
| 3.45 | Where can one find more information about ICAO CORSIA CERT? | |
| 3.46 | What are the five eligible Fuel Use Monitoring Methods? Are they different from ICAO CORSIA CERT? | |
| 3.47 | Is it necessary to describe all five Fuel Use Monitoring Methods in the Emissions Monitoring Plan, even if not all are used? | |
| 3.48 | Is it possible to use a Fuel Use Monitoring Method for reporting that is different to the method(s) described in the approved Emissions Monitoring Plan? | |
| 3.49 | Can an aeroplane operator change its Fuel Use Monitoring Method? | |
| 3.50 | What are the circumstances in which an aeroplane operator may change monitoring methods within a compliance period? | |
| 3.51 | Can an aeroplane operator use several different Fuel Use Monitoring Methods? | |
| 3.52 | Can an operator with annual CO2 emissions from international flights subject to offsetting requirements of less than 50 000 tonnes use the CERT for emissions subject to offsetting requirements but use a Fuel Use Monitoring Method for emissions not subject to offsetting? | |
| 3.53 | How should an aeroplane operator complete its Emissions Monitoring Plan when using the ICAO CORSIA CERT on emissions subject to offsetting requirements and a Fuel Use Monitoring Method on emissions not subject to offsetting requirements? | |
| 3.54 | How is “Block-off” and “Block-on” defined in Fuel Use Monitoring Method “Block-off / Block-on”? | |
| 3.55 | What are the data requirements for the Fuel Use Monitoring Method “Fuel Allocation with Block Hour”? | |
| 3.56 | How should missing data under the Fuel Use Monitoring Method “Fuel Allocation with Block Hour” be handled? | |
| 3.57 | What will happen if an aeroplane operator exceeds the eligibility threshold to use ICAO CORSIA CERT during a given year? | |
| 3.58 | How is fuel use treated while performing non-commercial activities (e.g., APU fuel use during maintenance)? | |
| 3.59 | How are CO2 emissions calculated from the fuel used? | |
| 3.60 | Why do we need to know total CO2 emissions from international aviation? | |
| 3.61 | What are the requirements for fuel density? | |
| 3.62 | What is the standard fuel density? | |
| 3.63 | How to account for the use of CORSIA Eligible Fuels in the CORSIA MRV system? | |
| Reporting | ||
| 3.64 | What is the timeline for reporting of CO2 emissions, and who will report to whom? | |
| 3.65 | Do all international routes have to be included in the Emissions Report, or only the international routes with the States that participate in the CORSIA offsetting? | |
| 3.66 | Who decides on the selection of aggregation level for the CO2 emissions data (State pair or aerodrome pair)? | |
| 3.67 | What is the level of aggregation of the CO2 emissions information that will be reported to States, and to ICAO? | |
| 3.68 | What is the ICAO tool to facilitate reporting of the necessary information from States to ICAO? | |
| 3.69 | Where can one find more information about the CORSIA Central Registry CCR? | |
| 3.70 | Are there any provisions regarding the confidentiality of data if a route is only operated by one operator? | |
| 3.71 | Are the reporting periods and compliance periods the same for all operators? | |
| 3.72 | Is there an established template for reporting annual CO2 emissions from an aeroplane operator to the State, and from the State to ICAO? | |
| 3.73 | What if there are gaps identified in the reported data? | |
| 3.74 | What constitutes a data gap? How can such data gaps be addressed? | |
| 3.75 | What is the threshold for using ICAO CORSIA CERT to fill data gaps? | |
| 3.76 | Is the 5 per cent data gap threshold based on CO2 emissions or number of flights? | |
| 3.77 | Is an alternative estimation approach (instead of using the ICAO CORSIA CERT) possible for addressing data gaps? | |
| 3.78 | Will CORSIA’s baseline emissions be affected due to an error correction to the Emissions Report? | |
| 3.79 | What happens in case of late reporting or no reporting by an aeroplane operator or a State? | |
| 3.80 | Who reports emissions from an aeroplane operator that has gone bankrupt during a reporting year? | |
| 3.81 | Why does a State need to provide State pair data to ICAO, even if this data has been identified as confidential? | |
| 3.82 | How does an aeroplane operator report the use of CORSIA Eligible Fuels? | |
| 3.83 | Why should an aeroplane operator report CORSIA Eligible Fuels every year while the compliance cycle is three years? | |
| 3.84 | What will be the process of reporting of emissions unit cancellations? | |
| Verification | ||
| 3.85 | How does the verification of CO2 emissions work in CORSIA? Who will do the verification? | |
| 3.86 | Is third-party verification a requirement under Annex 16, Volume IV? | |
| 3.87 | Did travel restrictions linked to the COVID-19 pandemic pose an exception to third-party verification requirements in CORSIA? | |
| 3.88 | Is it necessary for an aeroplane operator to perform an internal pre-verification of its Emissions Report, prior to the third-party verification? | |
| 3.89 | Does the voluntary pre-verification by an aeroplane operator substitute the third-party verification? | |
| 3.90 | Is a third-party verification needed when an aeroplane operator uses the ICAO CORSIA CERT? | |
| 3.91 | What are the requirements to be accredited as a verification body to conduct the third-party verification? | |
| 3.92 | Are the references to ISO standards included in Annex 16, Volume IV linked to specific versions of the standards, or will the latest version of these ISO standards automatically apply? | |
| 3.93 | What are the requirements for the verification of an Emissions Unit Cancellation Report? | |
| 3.94 | How much time is normally required for the third-party verification process? | |
| 3.95 | Who pays for the third-party verification and what will be the price? Is a price list included in the list of verification bodies to be compiled by ICAO? | |
| 3.96 | Who accredits the verification body? | |
| 3.97 | Is there any requirement for a verification body to be accredited by the National Accreditation Body (NAB) of the State it is registered in? | |
| 3.98 | Can a verification body be accredited by several National Accreditation Bodies (NABs)? | |
| 3.99 | Can a Civil Aviation Authority accredit verification bodies? | |
| 3.100 | Can an aeroplane operator become a verification body? | |
| 3.101 | How can an aeroplane operator identify an accredited verification body? | |
| 3.102 | What are the recommended steps to be taken by an aeroplane operator in order to identify an eligible verification body? | |
| 3.103 | Should an aeroplane operator submit a copy of the accreditation certificate of the verification body to States along with the Emissions Report? | |
| 3.104 | What can States do to check the accreditation status of verification bodies referred in the Emissions Report? | |
| 3.105 | Does the verification body have to be from the administrating State of an aeroplane operator? | |
| 3.106 | What if there is no accredited verification body in a State? | |
| 3.107 | What can a State do if it has limited accreditation structure in place to support the verification process? | |
| 3.108 | Must a State ensure to have accredited verification bodies through its national accreditation body? | |
| 3.109 | What may a witness audit involve during the accreditation process of a verification body? | |
| 3.110 | How does a verification team meet the knowledge requirements? | |
| 3.111 | How does a verification team meet the technical expertise requirements? | |
| 3.112 | How does an independent reviewer meet the knowledge and technical expertise requirements? | |
| 3.113 | To avoid conflicts of interest, the leader of the verification team cannot undertake more than six verifications without a three consecutive year break. What if the leader performs three verifications, stops for one year, and then performs another three verifications? | |
| 3.114 | What are the contents of a Verification Report? | |
| 3.115 | Is there a template for a Verification Report? | |
| 3.116 | What does “materiality” mean in connection to the verification of CO2 emissions? | |
| 3.117 | Does the verification body need to include non-material misstatements and non-conformities as a part of the Verification Report? | |
| 3.118 | Is a non-conformity acceptable if it does not lead to a material discrepancy? | |
| 3.119 | Is a site visit a requirement under Annex 16, Volume IV for the verification process in CORSIA? | |
| 3.120 | How can verification bodies conduct site visits in the event of travel restrictions caused by exceptional situations such as the COVID-19 pandemic? | |
| 3.121 | What should a State generally consider when coordinating with a verification body on a remote verification approach for Emissions Reports? | |
| 3.122 | What is the CORSIA-specific guidance available for verification bodies in order for them to undertake the remote verification of CORSIA Emissions Reports? | |
| 3.123 | Does the order of magnitude check by States require specific training, or is it enough to follow the checklist included in the ETM, Volume IV? | |
| 3.124 | What are the available sources of information for a State when conducting the order of magnitude check? | |
| 3.125 | Why do both the aeroplane operator and verification body submit Emission Report and Verification Report to the State? | |
| 3.126 | Does ICAO provide training on CORSIA verification requirements? | |
| 4. | Questions about CORSIA Implementation Elements | |
| CORSIA States for Chapter 3 State Pairs | ||
| 4.1 | What are "Chapter 3 State Pairs"? | |
| 4.2 | What is the ICAO document “CORSIA States for Chapter 3 State Pairs”? | |
| 4.3 | Where can the ICAO document “CORSIA States for Chapter 3 State Pairs” be found? | |
| ICAO CORSIA CO₂ Estimation and Reporting Tool (CERT) | ||
| 4.4 | What is ICAO CORSIA CERT? | |
| 4.5 | Why is the ICAO CORSIA CERT updated on an annual basis? | |
| 4.6 | What are the differences among the annual versions of the ICAO CORSIA CERT? | |
| 4.7 | Can an Emissions Report that was generated by the ICAO CORSIA CERT be submitted from an aeroplane operator to the State? | |
| 4.8 | Can the ICAO CORSIA CERT be used for an aeroplane operator’s internal pre-verification? | |
| 4.9 | Will the third-party verification of an Emissions Report be cheaper when an aeroplane operator has used the ICAO CORSIA CERT for monitoring? | |
| 4.10 | Where can one find more information about the ICAO CORSIA CERT? | |
| CORSIA Eligible Fuels | ||
| 4.11 | What is the definition of "CORSIA Eligible Fuels"? | |
| 4.12 | Which sustainability criteria shall be met by CORSIA Eligible Fuels? | |
| 4.13 | Which life cycle emissions values will be used for calculating the emissions reductions from CORSIA Eligible Fuels? | |
| 4.14 | What constitutes the life cycle emission value of a CORSIA Eligible Fuel? | |
| 4.15 | Who certifies CORSIA Eligible Fuel in order to be used in CORSIA? | |
| 4.16 | What are the requirements for Sustainability Certification Schemes? | |
| 4.17 | Where can one find a list of approved Sustainability Certification Schemes? | |
| 4.18 | Can an aeroplane operator claim all the CORSIA Eligible Fuel it has purchased? | |
| 4.19 | Can the same emission reduction from a CEF be claimed by the same aeroplane operator in different GHG schemes? | |
| 4.20 | Which measures are put in place to avoid double claiming in relation to CORSIA Eligible Fuels? | |
| 4.21 | Which date is relevant in order to claim a batch of CORSIA eligible fuel? | |
| 4.22 | Can a fuel producer obtain an ILUC value that is specific for its fuel? | |
| 4.23 | What is the process to request the calculation of a new default ILUC or core LCA value? | |
| 4.24 | What are emissions units, in general? | |
| CORSIA Eligible Emissions Units | ||
| 4.25 | What are the eligible emissions units to be used under CORSIA? | |
| 4.26 | What are the eligibility criteria for CORSIA Eligible Emissions Units? | |
| 4.27 | Can an aeroplane operator already start purchasing CORSIA Eligible Emissions Units? | |
| 4.28 | Can an aeroplane operator implement a project that generates CORSIA Eligible Emissions Units? | |
| 4.29 | Can an aeroplane operator cancel CORSIA Eligible Emissions Units prior to having received the total final offsetting requirements from the State at the end of a compliance cycle? | |
| 4.30 | What happens if an operator does not cancel enough CORSIA Eligible Emissions Units to meet its offsetting requirements? | |
| 4.31 | Which measures are put in place to avoid double claiming in relation to CORSIA Eligible Emissions Units? | |
| 4.32 | What is the "Technical Advisory Board" (TAB)? | |
| 4.33 | What are the tasks of the TAB? Who are the TAB members? | |
| 4.34 | What is the timeline for the work of TAB? | |
| 4.35 | How will the TAB adjust to changing contexts, such as decision at the UNFCCC? | |
| 4.36 | Where can one find more information about the TAB? | |
| CORSIA Central Registry (CCR) | ||
| 4.37 | What is the CORSIA Central Registry (CCR)? | |
| 4.38 | Who has access to the CCR? | |
| 4.39 | If an aeroplane operator is in a parent-subsidiary relationship, does the State need to list the subsidiary operator on the CCR? | |
| 4.40 | Should the list of aeroplane operators include operators which do not have any requirements under CORSIA? | |
| 4.41 | How can a State validate information contained in the list of verification bodies accredited in the State? | |
| 4.42 | What is the information that a State submits to ICAO in relation to accredited verification bodies? | |
| 4.43 | Will the lists of aeroplane operators and accredited verification bodies be updated on a regular basis? | |
| 4.44 | What information from the CCR will be made publicly available? | |
| 4.45 | What happens to data flagged as confidential by a State when ICAO receives it? | |
| 4.46 | How will the reporting of emissions units cancellations from States to ICAO work? | |
| 5. | Questions about the cost impact of CORSIA | |
| 5.1 | What is the estimated quantity to be offset under the CORSIA? | |
| 5.2 | What is the estimated compliance cost for the CORSIA offsetting requirements by aeroplane operators? | |
| 5.3 | What is the estimated administrative cost for the CORSIA implementation by States, aeroplane operators and ICAO. | |
| 6. | Questions about capacity-building and assistance for CORSIA implementation. | |
| 6.1 | What is ICAO "ACT CORSIA"? | |
| 6.2 | What are the activities covered under the ACT-CORSIA? | |
| 6.3 | What are CORSIA Buddy Partnerships? | |
| 6.4 | How many CORSIA Buddy Partnerships have been established under the ICAO ACT-CORSIA programme? | |
| 6.5 | What is ICAO's plan for continued capacity-building for CORSIA implementation? | |
| 6.6 | How can my State contribute to ACT-CORSIA ? |
