ETSO-2C521

• ED Decision 2022/018/R found in: CS-ETSO Amdt 17 - European Technical Standard Orders (Oct 2026)

#### ETSO-2C521 *ED Decision 2022/018/R* ##### Electronic Flight Bag (EFB) Software Applications **1 Applicability** This ETSO provides the requirements that electronic flight bag software applications that are designed on or after the date of this ETSO must meet in order to be identified with the applicable ETSO marking. **2 Procedures** 2.1 General The applicable procedures are detailed in CS-ETSO, [Subpart A](#_DxCrossRefBm920220672). 2.2 Specific None. **3 Technical conditions** 3.1 Basic 3.1.1 Minimum Performance Standard The applicable standard is that provided in EUROCAE ED-273, ‘Minimum Operational Performance Standard for Electronic Flight Bag (EFB) Software Applications’, dated August 2021. 3.1.2 Environmental Standard Not applicable. 3.1.3 Software See the software development assurance method described in EUROCAE ED-273, ‘Minimum Operational Performance Standard for Electronic Flight Bag (EFB) Software Applications’, Section 2.4. Alternatively, see CS-ETSO, Subpart A, paragraph 2.2. 3.1.4 Airborne Electronic Hardware Not applicable. 3.2 Specific 3.2.1 Failure Condition Classification A safety risk assessment must be performed per EUROCAE ED-273, ‘Minimum Operational Performance Standard for Electronic Flight Bag (EFB) Software Applications’, Section 2.2. The assumptions, mitigation and prevention means identified in this risk assessment must be made available to the aircraft operator as required by the standard. 3.2.2 Documentation The applicant shall develop and make available to the aircraft operator the application operational data as defined in EUROCAE ED-273, Chapter 4. **4 Marking** 4.1 General The application shall include a function permitting the user to retrieve the markings required by CS-ETSO, Subpart A, paragraph 1.2. Note: The date of the official release of the EFB software application is a means to comply with point 21.A.807(a)(3). 4.2 Specific None. **5 Availability of Referenced Documents** See CS-ETSO, Subpart A, paragraph 3. [Amdt ETSO/17]