FAQ n.142144

The classification criteria for “Basic” supplemental type certificates (STCs) are stipulated in Section 3.5.3.1 of the current Technical Implementing Procedures (TIP) for Airworthiness and Environmental Certification between the Federal Aviation Administration (FAA) and the European Union Aviation Safety Agency (EASA) and are listed below for your convenience.

Major design changes to a type certificate (TC), including STCs, are eligible for a “Basic” classification if not impacting any of the following items:

1. any item in the safety emphasis item (SEI) list of the validating authority (VA) (i.e. EASA in this case) as defined in Section 3.5.10.4;
2. the certification basis of the certificating authority (CA) (i.e. the FAA in this case) or of the VA includes or is anticipated to include a new or amended:
   • FAA exemption or EASA deviation,
   • special condition (SC), or
   • equivalent level of safety (ELOS/ESF);
3. a classification of “Significant” has been made by the CA in accordance with FAA 14 Code of Federal Regulations (CFR), Section 21.101(b) or EASA point 21.A.101(b) to Annex I (Part 21) to Commission Regulation (EU) No 748/2012;
4. an airworthiness directive (AD) is affected, which was unilaterally issued by the VA; or an AD is affected, which was issued by the VA, and where the VA is the Authority for the State of Design (SoD) of the TC;
5. changes involving the use of a new applicable method of compliance (MoC)^* or different from that previously agreed by the CA and the VA;
6. new technology^** exists;
7. novel applications of existing technology^*** exist;
8. the applicant has proposed to the CA non-simple substantiations of acoustic or emissions changes, whereas a simple substantiation is when the compliance demonstration with the CA has involved standard means of compliance and procedures that were already regularly agreed by the VA and CA in previous projects of the same applicant (using the same test organisation)  
   (Note: TIP Chapter 7.16 is more stringent and excludes any STC that has an impact on noise values (increase or decrease));
9. changes that have an appreciable effect on any one of the operational suitability data (OSD) constituents (refer to EASA Guidance Material GM 21.A.91 to determine an appreciable effect); and
10. any other design change designated as "Non-Basic" by the CA.

Note 1: Please consult the EASA lists of SEIs for General Aviation and Rotorcraft.

Note 2: Please note that this information is typically quoted in the FAA STC.

^* A method of compliance would not be considered “new” or “different” if it had been previously applied in a similar context by both the CA and the VA.

^** New technology is technology that is new to the VA as a whole, not just new to the VA team members. For example, if technology used by the applicant were new to the VA team, but not to the VA itself, it would not be considered new. It is the VA management’s responsibility to make sure the VA team members are properly informed of the earlier use of the technology, VA standards, and MoC.

^*** Novel application of technology is where a particular technology is being used in a manner that causes the precepts of the technology to be questioned. However, it does not mean that existing technology being applied for the first time to a particular product line is automatically novel. Additionally, novel applies to the VA as a whole, not just to a project being assessed by the specific VA team members.

Note 3: Please note that applicants may not have all the elements and information required for a correct classification. Therefore, the classification proposed by the applicant may be questioned by EASA and eventually not accepted.