5W Research published the "Airlines & Hotels AI Visibility Index 2026," measuring how often roughly 50 leading airline and hotel brands are cited inside major AI platforms including ChatGPT, Claude, Perplexity, Gemini, and Google AI Overviews. The Index analyzed more than 60 travel-related prompts and reports a strong concentration of citations: in several subcategories the top three brands account for over 70 percent of citation share. The study finds that loyalty program scale and paid-media budgets are not consistent predictors of AI citation share, while earned media and editorial footprint correlate with visibility. Estimated brand citation shares show Delta at 10.5%, Marriott at about 10%, Hilton at 8.5%, United at 7.5%, and American at 6.5% in the Index's ranking. The Index operationalizes "AI visibility" as citation share inside model outputs and answer-overview products rather than as search-engine ranking.