Operational Suitability Data

Operational Suitability Data


The concept of operational suitability data (OSD) draws its origins from the operational evaluation board (OEB) existing under the Joint Aviation Authorities (JAA). Operational evaluations have been conducted by the JAA and then by the European Union Aviation Safety Agency (EASA) since 1997. Under the OEB scheme aircraft manufacturers submitted, on a voluntary basis, recommendations for the approval of aircraft type rating training courses (flight and cabin crew) and the minimum equipment lists (MELs).

OEB reports have been published on the EASA website in support of approved training organisations (ATOs) and air operators for the aircraft, equipment and/or operations evaluated under the OEB reports.


The European Commission has published a new requirement in aircraft certification with regard to operational suitability data, thereby mandating that aircraft manufacturers submit data EASA considers important for safe operations. Under Commission Regulation (EU) No 69/2014 of 27 January 2014 amending Regulation (EU) No 748/2012 laying down implementing rules for the airworthiness and environmental certification of aircraft and related products, parts and appliances (Part-21), the data is to be approved by EASA under the aircraft type certificate and then used by air operators and flight and maintenance training organisations. The mandatory OSD succeeds the voluntary OEB process.

There exist five categories of OSD and these cover: pilot training, cabin crew training, the master minimum equipment list (MMEL), maintenance staff training and simulator qualification.

It is under Commission Regulation (EU) No 70/2014 of 27 January 2014 amending Regulation (EU) No 1178/2011 (itself laying down technical requirements and administrative procedures related to civil aviation aircrew (EASA AIR CREW) that the use of OSD is mandated and regulated for approved training organisations. Commission Regulation (EU) No 71/2014 of 27 January 2014 amending Regulation (EU) No 965/2012 (EASA AIR OPS which lays down technical requirements and administrative procedures related to air operations) mandates and regulates the use of OSD by air operators in the EU. Requirements regarding the use of OSD by Part-147 approved maintenance training organisations have yet to be published.

In Practice

The process begins when the aircraft manufacturer proposes what data EASA will evaluate against the rule for approval. OSD are approved as part of the type certificate like the airplane flight manual, and are referenced in the applicable type certificate data sheet (TCDS). Since the holder of the type certificate is the owner of OSD, the manufacturer is required to keep the data current.

The OSD then becomes the reference document for customised training and for MELs as developed by the users of the OSD (air operators and training organisations). OSD has both mandatory and recommended elements and it is up to the national aviation authorities (NAAs) to determine whether users must comply with a recommendation. Pilot qualification is at the heart of OSD. It defines a minimum syllabus for a type rating, as well as training areas of special emphasis.

EASA has provided a transition period for the industry to comply with new OSD requirement. MMELs for in-production models, for example, must be approved by 18/12/2015, or before the aircraft is operated by an EU operator, whichever is the latest.

Certification Specifications Certification specifications (CS) with regard to operational suitability data are provided as follows:

  • Certification Specifications for Operational Suitability Data (OSD) Flight Crew Data (CS-FCD)
  • Certification Specifications and Guidance Material for Cabin Crew Data (CS-CCD)
  • Certification Specifications and Guidance Material for Generic Master Minimum Equipment List (CS-GEN-MMEL, applies to other-than-complex motor-powered aeroplanes except for very light aeroplanes (VLA), light sport aeroplanes (LSA) and powered sailplanes)
  • Certification Specifications and Guidance Material for Master Minimum Equipment List (CS-MMEL, applicable to complex motor-powered aircraft)
  • Certification Specifications and Guidance Material for Simulator Data (CS-SIMD)

Related Articles

Further Reading


SKYbrary Partners:

Safety knowledge contributed by: