  [Context & motivation] Eliciting requirements that are detailed and logical
enough to be amenable to formal verification is a difficult task. Multiple
tools exist for requirements elicitation and some of these also support
formalisation of requirements in a way that is useful for formal methods.
[Question/problem] This paper reports on our experience of using the FRET
alongside our industrial partner. The use case that we investigate is an
aircraft engine controller. In this context, we evaluate the use of FRET to
bridge the communication gap between formal methods experts and aerospace
industry specialists. [Principal ideas/results] We describe our journey from
ambiguous, natural-language requirements to concise, formalised FRET
requirements. We include our analysis of the formalised requirements from the
perspective of patterns, translation into other formal methods and the
relationship between parent-child requirements in this set. We also provide
insight into lessons learned throughout this process and identify future
improvements to FRET. [Contribution] Previous experience reports have been
published by the FRET team, but this is the first such report of an industrial
use case that was written by researchers that have not been involved FRET's
development.
