OSO 4 – UAS components are designed to an Airworthiness Standard
AMC1 Article 11 Annex E. Operational Safety Objective 4
CAA ORS9 Decision No. 46
OSO 4 – UAS components are designed to an Airworthiness Standard
Level of integrity
| Criterion | Low (SAIL 4) | Medium (SAIL 5) | High (SAIL 6) |
|---|---|---|---|
| Criterion | OSO4.L.I |
OSO4.M.I |
OSO4.H.I |
| Alternative FTB method | OSO4.FT.L.I |
Not applicable |
Not applicable |
Level of assurance
| Criterion | Low (SAIL 4) | Medium (SAIL 5) | High (SAIL 6) |
|---|---|---|---|
| Criterion | OSO4.L.A |
OSO4.M.A |
OSO4.H.A |
| Alternative FTB method | OSO4.FT.L.A |
Not applicable |
Not applicable |
Low level of robustness (SAIL 4)
OSO4.L.I
The UAS components essential to safe operations must be designed to an Airworthiness Design Standard considered adequate by the CAA and/or in accordance with a means of compliance acceptable to the CAA to contribute to the overall safety objective of 10-4/FH for the loss of control of the operation.
OSO4.FT.L.I
The applicant must conduct at least 30,000 FTB flight hours meeting one of the set of conditions described in FTB policy.
OSO4.L.A
(a) The Applicant must declare and provide evidence of compliance with the Integrity requirements. The detailed evidence of compliance may be assessed by the CAA.
(b) If compliance evidence is provided through simulation, the validity of the target environment used in the simulation must be justified.
OSO4.FT.L.A
(a) The FTB flying hours must be conducted per a standard or means of compliance acceptable to the CAA.
(b) The Applicant must declare and provide evidence of compliance with the Integrity requirements. The detailed evidence of compliance may be assessed by the CAA.
AMC.OSO4.L.I
Annex E – AMC 1 Integrity and assurance levels for the Operational Safety Objectives (OSO) paragraph 1.5 provides further information about proposing a standard as an AMC.
AMC.OSO4.FT.L.A
Annex E – AMC 1 Integrity and assurance levels for the Operational Safety Objectives (OSO) paragraph 1.5 provides further information about proposing a standard as an AMC.
Medium level of robustness (SAIL 5)
Lower robustness level requirements to be complied with:
• None
Additional requirements to be compiled with:
OSO4.M.I
The UAS components essential to safe operations must be designed to an Airworthiness Design Standard considered adequate by the CAA and/or in accordance with a means of compliance acceptable to the CAA to contribute to the overall safety objective of 10-5/FH for the loss of control of the operation.
OSO4.M.A
The Applicant must provide evidence of compliance with the Integrity requirements, which will be assessed by the CAA.
High level of robustness (SAIL 6)
Lower robustness level requirements to be complied with:
• None
OSO4.H.I
The UAS components essential to safe operations must be designed to an Airworthiness Design Standard considered adequate by the CAA and/or in accordance with a means of compliance acceptable to the CAA to contribute to the overall safety objective of 10-6/FH for the loss of control of the operation.
OSO4.H.A
The Applicant must provide evidence of compliance with the Integrity requirements, which will be assessed by the CAA. The CAA will validate continuing compliance through oversight.
GM1 Article 11 Annex E. Operational Safety Objective 4
CAA ORS9 Decision No. 46
GM.OSO4
(a) The UAS components essential to safe operations are those whose failure would significantly impair the capability of the Operator to meet the target level of safety for loss of control of the operation.
(b) Starting at SAIL 4, it is considered that the safety objective associated with the SAIL of the operation (e.g. probability of loss of control of the operation below 10-4/FH for a SAIL 4 operation) may not be achieved without UAS components essential to safe operation being designed to an Airworthiness Design Standard, (unless a Functional Test Based (FTB) approach is chosen).
(c) OSO 4 does not duplicate requirements that are addressed by other design related OSOs. OSO 4 aims at ensuring that the UAS as a whole is designed according to an Airworthiness Design Standard (e.g. the design and construction, structure, flight performance are addressed by the standard), whereas other design related OSOs focus on specific systems or functionalities of the UAS and or specific technical disciplines:
(1) OSO 5 (system safety)
(2) OSO 6 (C3 Link)
(3) OSO 7 (UAS conformity check)
(4) OSO 13 (external services)
(5) OSO 18 (automatic protection of the flight envelope)
(6) OSO 20 (HMI)
(7) OSO 23, 24 (environmental conditions).
GM.OSO4.L.I
The Applicant is free to propose their own Airworthiness Design Standard(s) to the CAA. When aspects of an Airworthiness Design Standard are covered by an OSO (e.g. OSO 5), the OSO requirement takes precedence.
GM.OSO4.L.A
(a) Compliance evidence is typically provided through testing, analysis, simulation, inspection, design review or through operational experience.