Lavionic DAL Assignment Helper

• The most severe classification of the top-level failure condition: Catastrophic, Hazardous, Major, Minor or No safety effect, from your functional hazard assessment.
• The number of members of the functional failure set.
• Whether the members are functionally independent, and whether the items are developed independently.
• Option 1 (one member keeps the top level) or option 2 (two members share a lower level).

• The FDAL of the top-level function.
• The FDAL and IDAL of each member, in a figure of the architecture.
• The level of the independence claim, which stays at the top-level FDAL.
• An edit panel: change one answer and the result follows at once.

Use it online in your browser, or download it once as one HTML file. The file opens in Chrome, Safari, Edge or Firefox, works without an internet connection and sends no data anywhere.

The helper gives a first reading of the general principles, in own words. The applicant's safety assessment and the competent authority decide the levels.

The helper is an aid, not a means of compliance.

• ARP4754B / ED-79B 5.2.1 and 5.2.3 (in own words)