Objective: The present study explored how a customized leadership development program (LDP) with coursework taught in English to non-native English speakers could optimize English language fluency in Brazil airline leaders.

Background: Currently, problems exist with a myriad of native language accents and phraseology interfering with cognitive reflexes especially for aircrews and air traffic controllers to safely do their work. Executives from four Brazilian airlines proactively implemented a 14-month LDP focused on English language fluency and leadership enhancements collectively for leaders within their firms.

Method: Blended learning as proposed by the International Civil Aviation Organization provided the experiential and heuristic framework of the LDP suitable for an empirical analysis of participants’ language and leadership improvements.

Results: Research outcomes indicated Interaction Ritual Theory and Social Contagion Theory moderating entrained behaviors, emotions, and modes of LDP participants, upskilling their English language fluency and leadership competencies. LDP participants with no prior relationships progressed through the LDP wholly as a collective group prioritizing their language and leadership proficiencies.

Conclusion: Optimization of English language fluency for aviation leaders can be accomplished in a lengthy customized leadership development program. Upskilling language proficiency for leaders assists them with transferring and motivating English language knowledge and fluency to their teams and organizationally.