  Automotive companies increasingly adopt scaled agile methods to allow them to
deal with their organisational and product complexity. Suitable methods are
needed to ensure safety when developing automotive systems. On a small scale,
R-Scrum and SafeScrum are two concrete suggestions for how to develop
safety-critical systems using agile methods. However, for large-scale
environments, existing frameworks like SAFe or LeSS do not support the
development of safety-critical systems out of the box. We, therefore, aim to
understand which challenges exist when developing safety-critical systems
within large-scale agile industrial settings, in particular in the automotive
domain. Based on an analysis of R-Scrum and SafeScrum, we conducted a focus
group with three experts from industry to collect challenges in their daily
work. We found challenges in the areas of living traceability, continuous
compliance, and organisational flexibility. Among others, organisations
struggle with defining a suitable traceability strategy, performing incremental
safety analysis, and with integrating safety practices into their scaled way of
working. Our results indicate a need to provide practical approaches to
integrate safety work into large-scale agile development and point towards
possible solutions, e.g., modular safety cases.
  Keywords: Scaled Agile, Safety-Critical Systems, Software Processes, R-Scrum,
SafeScrum
